Filed Pursuant to Rule 424(b)(5)
Registration Statement No. 333-234537

Calculation of Registration Fee

PROSPECTUS SUPPLEMENT TO PROSPECTUS DATED NOVEMBER 6, 2019

$120,000,000

4.00% Convertible Senior Notes due 2026

Offering Price 100%

We are offering $120,000,000 aggregate principal amount of our 4.00% convertible senior notes due 2026, or the notes. In addition, we have granted the underwriters an option, exercisable for a period of 30 days from the date of this prospectus supplement, to purchase up to an additional $18,000,000 aggregate principal amount of notes, solely to cover over-allotments. The notes will mature on November 15, 2026, unless earlier repurchased, redeemed or converted.

We will pay interest on the notes at an annual rate of 4.00%, payable semi-annually in arrears on May 15 and November 15 of each year, beginning on May 15, 2020.

Noteholders may convert their notes at their option only in the following circumstances: (1) during any calendar quarter commencing after the calendar quarter ending on March 31, 2020 (and only during such calendar quarter), if the last reported sale price per share of our common stock for each of at least 20 trading days, whether or not consecutive, during the period of 30 consecutive trading days ending on, and including, the last trading day of the immediately preceding calendar quarter exceeds 130% of the conversion price on the applicable trading day; (2) during the five consecutive business days immediately after any 10 consecutive trading day period (such 10 consecutive trading day period, the “measurement period”) if the trading price (as defined in this prospectus supplement) per $1,000 principal amount of notes for each trading day of the measurement period was less than 98% of the product of the last reported sale price per share of our common stock on such trading day and the conversion rate on such trading day; (3) upon the occurrence of certain corporate events or distributions on our common stock, as described in this prospectus supplement; (4) if we call the notes for redemption; and (5) at any time from, and including, July 15, 2026 until the close of business on the scheduled trading day immediately before the maturity date. We will settle conversions by paying or delivering, as applicable, cash, shares of our common stock or a combination of cash and shares of our common stock, at our election, based on the applicable conversion rate(s). The initial conversion rate is 94.7811 shares per $1,000 principal amount of notes, which represents an initial conversion price of approximately $10.55 per share, and is subject to adjustment as described in this prospectus supplement. If a “make-whole fundamental change” (as defined in this prospectus supplement) occurs, then we will in certain circumstances increase the conversion rate for a specified period of time.

The notes will be redeemable, in whole or in part, at our option at any time, and from time to time, on or after November 20, 2023 and, in the case of any partial redemption, on or before the 60th scheduled trading day before the maturity date, at a cash redemption price equal to the principal amount of the notes to be redeemed, plus accrued and unpaid interest, if any, to, but excluding, the redemption date but only if the last reported sale price per share of our common stock exceeds 130% of the conversion price on (1) each of at least 20 trading days, whether or not consecutive, during the 30 consecutive trading days ending on, and including, the trading day immediately before the date we send the related redemption notice; and (2) the trading day immediately before the date we send such notice. In addition, calling any note for redemption will constitute a make-whole fundamental change with respect to that note, in which case the conversion rate applicable to the conversion of that note will be increased in certain circumstances if it is converted after it is called for redemption.

If a “fundamental change” (as defined in this prospectus supplement) occurs, then, except as described in this prospectus supplement, noteholders may require us to repurchase their notes at a cash repurchase price equal to the principal amount of the notes to be repurchased, plus accrued and unpaid interest, if any, to, but excluding, the fundamental change repurchase date.

The notes will be our general unsecured obligations and will: rank senior in right of payment to all of our indebtedness that is expressly subordinated in right of payment to the notes; rank equal in right of payment with all of our indebtedness that is not so subordinated; effectively rank junior to any of our secured indebtedness to the extent of the value of the assets securing such indebtedness; and rank structurally junior to all indebtedness and other liabilities of our subsidiaries (including trade payables, but excluding intercompany obligations and liabilities of a type not required to be reflected on a balance sheet of such subsidiaries in accordance with generally accepted accounting principles, or GAAP).

No public market currently exists for the notes, and we do not intend to apply to list the notes on any securities exchange or for quotation on any inter-dealer quotation system. Our common stock is listed on The Nasdaq Global Select Market under the symbol “CYTK.” On November 7, 2019, the last reported sale price of our common stock was $8.275 per share.

Investing in the notes involves risks. See “Risk Factors” beginning on page S-18.

Neither the Securities and Exchange Commission nor any state or foreign securities commission or regulatory authority has approved or disapproved of the notes or the shares of our common stock, if any, issuable upon the conversion of the notes or passed upon the adequacy or accuracy of this prospectus supplement or the accompanying prospectus. Any representation to the contrary is a criminal offense.

We expect to deliver the notes in book-entry form through the facilities of The Depository Trust Company on or about November 13, 2019.

Prospectus supplement dated November 7, 2019.

TABLE OF CONTENTS

In deciding whether to purchase the notes, you should rely only on the information contained or incorporated by reference in this prospectus supplement and the accompanying prospectus and any related free writing prospectus we authorize for use in connection with this offering. Neither we nor any of the underwriters has authorized anyone to provide you with additional or different information. If anyone provides you with additional or different information, you should not rely on it.

You should not assume that the information included or incorporated by reference in this prospectus supplement or the accompanying prospectus or any related free writing prospectus we authorize for use in connection with this offering is accurate as of any date other than the respective dates of the documents in which the information is contained. Our business, financial condition, results of operations and prospects could have changed since those dates.

You should not consider any information included or incorporated by reference in this prospectus supplement or the accompanying prospectus to be legal, tax or investment advice. You should consult your own counsel, accountant and other advisors for legal, tax, business, financial and related advice regarding any purchase of the notes. Neither we nor any of the underwriters makes any representation regarding the legality of an investment in the notes by any person under applicable investment or similar laws.

This prospectus supplement and the accompanying prospectus do not constitute an offer to sell or the solicitation of an offer to purchase any notes in any jurisdiction or to any person where the offer or solicitation is not permitted.

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ABOUT THIS PROSPECTUS SUPPLEMENT

This document consists of two parts. The first part is this prospectus supplement, which describes the specific terms of this offering and also adds to and updates the information contained in the accompanying prospectus and the documents incorporated by reference into this prospectus supplement and the accompanying prospectus. The second part, the accompanying prospectus, gives more general information, some of which may not apply to this offering. If there is a difference between the information contained in this prospectus supplement, on the one hand, and the information contained in the accompanying prospectus or any document incorporated by reference, on the other hand, you should rely on the information in this prospectus supplement. Generally, when we refer to the prospectus, we are referring to this prospectus supplement and the accompanying prospectus combined.

We have not, and the underwriters have not, authorized anyone else to provide you with information that is in addition to or different from that contained or incorporated by reference in this prospectus supplement and the accompanying prospectus, along with the information contained in any permitted free writing prospectuses we have authorized for use in connection with this offering. We take, and the underwriters take, no responsibility for, and can provide no assurance as to the reliability of, any other information that others may give you. We are offering to sell, and seeking offers to buy, notes only in jurisdictions where offers and sales are permitted. The information contained in this prospectus supplement and the accompanying prospectus, along with any authorized free writing prospectus is accurate only as of the date of this prospectus supplement or the date of the accompanying prospectus, and the information in the documents incorporated by reference in this prospectus supplement and the accompanying prospectus is accurate only as of the date of those respective documents, regardless of the time of delivery of this prospectus supplement and the accompanying prospectus or of any sale of notes. Our business, financial condition, results of operations and prospects may have changed since those dates. It is important for you to read and consider all information contained or incorporated by reference in this prospectus supplement and the accompanying prospectus in making your investment decision. You should read this prospectus supplement and the accompanying prospectus, as well as the documents incorporated by reference into this prospectus supplement and the accompanying prospectus, any authorized free writing prospectus, and the additional information described under “Where You Can Find More Information” in this prospectus supplement and in the accompanying prospectus, before investing in our securities.

Neither we nor the underwriters have done anything that would permit this offering or possession or distribution of this prospectus supplement and the accompanying prospectus in any jurisdiction where action for that purpose is required, other than in the United States. Persons who come into possession of this prospectus supplement, the accompanying prospectus and any free writing prospectus related to this offering in jurisdictions outside the United States are required to inform themselves about and to observe any restrictions as to this offering and the distribution of this prospectus supplement, the accompanying prospectus and any such free writing prospectus applicable to that jurisdiction.

This document has been prepared on the basis that any offer of securities in any relevant European Economic Area member state will be made pursuant to an exemption under European prospectus law from the requirement to publish a prospectus for offers of securities and does not constitute an offer to or solicitation of anyone to purchase securities in any jurisdiction in which such offer or solicitation is not authorized, nor to any person to whom it is unlawful to make such an offer or solicitation.

This prospectus supplement and the accompanying prospectus, including the information incorporated by reference into this prospectus supplement and the accompanying prospectus, and any free writing prospectuses we have authorized for use in connection with this offering, include trademarks, service marks and trade names owned by us or other companies. All trademarks, service marks and trade names included or incorporated by reference into this prospectus supplement and the accompanying prospectus, and any free writing prospectuses we have authorized for use in connection with this offering, are the property of their respective owners.

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RISK FACTORS

Investing in our securities involves a high degree of risk. Before you decide to invest in our securities, you should carefully consider the risks and uncertainties described below together with all other information contained in this prospectus supplement, the accompanying prospectus and any free writing prospectus that we have authorized for use in connection with this offering, and in our filings with the SEC that we have incorporated by reference in this prospectus supplement and the accompanying prospectus. If any of such risks actually occurs, our business, prospects, operating results and financial condition could suffer materially. In such event, the trading price of our common stock could decline and you might lose all or part of your investment. Additional risks and uncertainties not presently known to us or that we currently deem immaterial may also impair our business.

Risks Related to the Notes and This Offering

Our indebtedness and liabilities could limit the cash flow available for our operations, expose us to risks that could adversely affect our business, financial condition and results of operations and impair our ability to satisfy our obligations under the notes.

As of September 30, 2019, we had $45 million aggregate principal amount of indebtedness, all of which was senior secured indebtedness under the Term Loan. We will incur $120.0 million (or, if the underwriters fully exercise their overallotment option, $138.0 million) of additional indebtedness as a result of this offering. Subject to any restrictions contained in the Term Loan or any agreements governing our future indebtedness, we may also incur additional indebtedness to meet future financing needs. Our indebtedness could have significant negative consequences for our security holders and our business, results of operations and financial condition by, among other things:

Our business may not generate sufficient funds, and we may otherwise be unable to maintain sufficient cash reserves, to pay amounts due under our indebtedness, including the notes, and our cash needs may increase in the future. In addition, any future indebtedness that we may incur may contain financial and other restrictive covenants that limit our ability to operate our business, raise capital or make payments under our other indebtedness. If we fail to comply with these covenants or to make payments under our indebtedness when due, then we would be in default under that indebtedness, which could, in turn, result in that and our other indebtedness becoming immediately payable in full.

We may be unable to raise the funds necessary to repurchase the notes for cash following a fundamental change, or to pay any cash amounts due upon conversion, and our future indebtedness may limit our ability to repurchase the notes or pay cash upon their conversion.

Noteholders may require us to repurchase their notes following a fundamental change at a cash repurchase price equal to the principal amount of the notes to be repurchased, plus accrued and unpaid interest to, but

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excluding, the fundamental change repurchase date. See “Description of Notes—Fundamental Change Permits Noteholders to Require Us to Repurchase Notes” In addition, upon conversion, we will satisfy part or all of our conversion obligation in cash unless we elect to settle conversions solely in shares of our common stock.

We may not have enough available cash or be able to obtain financing at the time we are required to repurchase the notes or pay the cash amounts due upon conversion of the notes. In addition, applicable law, regulatory authorities and the agreements governing our existing and future indebtedness may restrict our ability to repurchase the notes or pay the cash amounts due upon conversion of the notes. Our failure to repurchase notes or to pay the cash amounts due upon conversion of the notes when required will constitute a default under the base and supplemental indentures that will govern the notes, which we refer to collectively as the “indenture.” A default under the indenture or the fundamental change itself could also lead to a default under agreements governing our other indebtedness, which may result in that other indebtedness becoming immediately payable in full. We may not have sufficient funds to satisfy all amounts due under the other indebtedness and the notes.

Not all dilutive events will result in an adjustment to the conversion rate.

We will adjust the conversion rate of the notes for certain events, including:

See “Description of Notes—Conversion Rights—Conversion Rate Adjustments.” We are not required to adjust the conversion rate for other events, such as an issuance of common stock (or securities exercisable for, or convertible into, common stock) for cash, that may adversely affect the trading price of the notes and our common stock. An event may occur that adversely affects the noteholders and the trading price of the notes and the underlying shares of our common stock but that does not result in an adjustment to the conversion rate.

Redemption may adversely affect your return on the notes.

The notes will be redeemable, in whole or in part, at our option at any time, and from time to time, on a redemption date occurring on or after November 20, 2023 and, in the case of a partial redemption, on or before the 60th scheduled trading day before the maturity date, at a cash redemption price equal to the principal amount of the notes to be redeemed, plus accrued and unpaid, if any, but only if the last reported sale price per share of our common stock exceeds 130% of the conversion price on (1) each of at least 20 trading days, whether or not consecutive, during the 30 consecutive trading days ending on, and including, the trading day immediately before the date we send the related redemption notice; and (2) the trading day immediately before the date we send such notice. As a result, we may choose to redeem some or all of the notes, including at times when prevailing interest rates are relatively low. As a result, you may not be able to reinvest the proceeds you receive from the redemption in a comparable security at an effective interest rate as high as the interest rate on your notes being redeemed. In addition, holders who convert in advance of any redemption would not get any compensation for the lost option value of their notes. See “Description of Notes—Optional Redemption.”

Not all significant restructuring transactions will constitute a fundamental change, in which case you will not have the right to require us to repurchase your notes for cash.

If certain corporate events called “fundamental changes” occur, you will have the right to require us to repurchase your notes for cash. See “Description of Notes—Fundamental Change Permits Noteholders to

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Require Us to Repurchase Notes.” However, the definition of “fundamental change” is limited to specific corporate events and does not include all events that may adversely affect our financial condition or the trading price of the notes. For example, a leveraged recapitalization, refinancing, restructuring or acquisition by us may not constitute a fundamental change that would require us to repurchase the notes. Nonetheless, these events could significantly increase the amount of our indebtedness, harm our credit rating or adversely affect our capital structure and the trading price of the notes.

The increase to the conversion rate resulting from a make-whole fundamental change may not adequately compensate noteholders for the lost option value of their notes. In addition, a variety of transactions that do not constitute a make-whole fundamental change may significantly reduce the option value of the notes without a corresponding increase to the conversion rate.

If certain corporate events that constitute a “make-whole fundamental change” occur, then we will, in certain circumstances, temporarily increase the conversion rate. See “Description of Notes—Conversion Rights—Increase in Conversion Rate in Connection with a Make-Whole Fundamental Change.” The amount of the increase to the conversion rate will depend on the date on which the make-whole fundamental change becomes effective and the applicable “stock price.” While the increase to the conversion rate is designed to compensate noteholders for the lost option value of their notes resulting from a make-whole fundamental change, the increase is only an approximation and may not adequately compensate noteholders for the loss in option value. In addition, if the applicable “stock price” is greater than $150.00 per share or less than $8.275 per share (in each case, subject to adjustment), then we will not increase the conversion rate for the make-whole fundamental change. Moreover, we will not increase the conversion rate pursuant to these provisions to an amount that exceeds 120.8459 shares per $1,000 principal amount of notes, subject to adjustment.

Furthermore, the definition of make-whole fundamental change is limited to certain specific transactions. Accordingly, the make-whole fundamental change provisions of the indenture will not protect noteholders from other transactions that could significantly reduce the option value of the notes. For example, a spin-off or sale of a subsidiary or business division with volatile earnings, or a change in our line of business, could significantly affect the trading characteristics of our common stock and reduce the option value of the notes without constituting a make-whole fundamental change that results in a temporary increase to the conversion rate.

In addition, our obligation to increase the conversion rate in connection with a make-whole fundamental change could be considered a penalty, in which case its enforceability would be subject to general principles of reasonableness and equitable remedies.

There is currently no trading market for the notes. If an active trading market for the notes does not develop, then noteholders may be unable to resell their notes at desired times or prices, or at all.

The notes are a new class of securities for which no market currently exists. We do not intend to apply to list the notes on any securities exchange or for quotation on any inter-dealer quotation system. Although the underwriters have advised us that they intend to make a market in the notes, they not obligated to do so and may discontinue any market-making activity at any time and without notice. Accordingly, an active market for the notes may never develop, and, even if one develops, it may not be maintained. If an active trading market for the notes does not develop or is not maintained, then the market price and liquidity of the notes will be adversely affected and noteholders may not be able to resell their notes at desired times or prices, or at all.

The liquidity of the trading market, if any, and future trading prices of the notes will depend on many factors, including, among other things, the trading price of our common stock, prevailing interest rates, our dividend yield, financial condition, results of operations, business, prospects and credit quality relative to our competitors, the market for similar securities and the overall securities market. Many of these factors are beyond our control. Historically, the market for convertible debt has been volatile. Market volatility could significantly harm the market for the notes, regardless of our financial condition, results of operations, business, prospects or credit quality.

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The notes will be effectively subordinated to our future secured indebtedness and structurally subordinated to the liabilities of our subsidiaries.

The notes will be our general unsecured obligations that will rank senior in right of payment to all of our indebtedness that is expressly subordinated in right of payment to the notes, equal in right of payment with all of our indebtedness that is not so subordinated and effectively rank junior to any of our secured indebtedness to the extent of the value of the assets securing such indebtedness. In addition, because none of our subsidiaries will guarantee the notes, the notes will be structurally junior to all indebtedness and other liabilities of our subsidiaries (including trade payables, but excluding intercompany obligations and liabilities of a type not required to be reflected on a balance sheet of such subsidiaries in accordance with GAAP). The indenture will not prohibit us from incurring additional indebtedness, including secured indebtedness, which would be effectively senior to the notes to the extent of the value of the collateral securing that indebtedness, or indebtedness that would rank equal in right of payment with the notes. The indenture will also not prohibit our subsidiaries from incurring any additional indebtedness or other liabilities that would be structurally senior to our obligations under the notes.

In the event of our bankruptcy, liquidation, reorganization or other winding up, our assets that secure any indebtedness will not be available to make payments under the notes unless all of that indebtedness is first paid in full. We advise you that there may not be sufficient assets remaining to pay amounts due on any or all the notes then outstanding. In the event of the bankruptcy, liquidation, reorganization or other winding up of any of our subsidiaries, we, as a common equity holder of that subsidiary, and, therefore, the noteholders, will rank behind that subsidiary’s creditors, including that subsidiary’s trade creditors, and (to the extent we are not a holder thereof) that subsidiary’s preferred equity holders, if any. Even if we were a creditor of any of our subsidiaries, our rights as a creditor would be effectively subordinated to any security interest of others in the assets of that subsidiary, to the extent of the value of those assets, and would be subordinated to any indebtedness of that subsidiary that is senior in right of payment to that held by us.

Our subsidiaries will have no obligations under the notes. The ability of our subsidiaries to pay dividends or make other payments to us may be restricted by, among other things, corporate and other laws and by agreements to which our subsidiaries may become a party. Accordingly, we may be unable to gain access to the cash flow or assets of our subsidiaries to enable us to make payments on the notes.

As of September 30, 2019, we had $45 million aggregate principal amount of indebtedness, all of which was senior secured indebtedness under the Term Loan. After giving effect to the issuance of the notes (assuming no exercise of the underwriters’ over-allotment option), our total consolidated indebtedness for borrowed money would have been approximately $165 million in principal amount.

The trading price of our common stock and other factors could significantly affect the trading price of the notes.

We expect that the trading price of our common stock will significantly affect the trading price of the notes, which could result in greater volatility in the trading price of the notes than would be expected for non-convertible securities. The trading price of our common stock will likely continue to fluctuate in response to the factors described or referred to elsewhere in this section and under the caption “Disclosure Regarding Forward-Looking Statements,” among others, many of which are beyond our control.

The issuance or sale of shares of our common stock, or rights to acquire shares of our common stock, could depress the trading price of our common stock and the notes.

We may conduct future offerings of our common stock, preferred stock or other securities that are convertible into or exercisable for our common stock to finance our operations or fund acquisitions, or for other purposes. In addition, as of September 30, 2019, we had reserved 7,786,764 shares of common stock for issuance

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upon the exercise of outstanding options, 165,424 shares of common stock for issuance upon the exercise of outstanding warrants, 866,625 shares of common stock reserved for the vesting of outstanding restricted and performance stock units and 4,534,814 shares of common stock for future issuance under our stock option plans and employee stock purchase plans. The indenture for the notes will not restrict our ability to issue additional equity securities in the future. If we issue additional shares of our common stock or rights to acquire shares of our common stock, if any of our existing stockholders sells a substantial amount of our common stock, or if the market perceives that such issuances or sales may occur, then the trading price of our common stock, and, accordingly, the notes may significantly decrease. In addition, our issuance of additional shares of common stock will dilute the ownership interests of our existing common stockholders, including noteholders who have received shares of our common stock upon conversion of their notes.

We will make only very limited covenants in the indenture, and these limited covenants may not protect your investment.

Many debt instruments contain provisions that are designed to restrict the borrower’s activities and operations in a manner that is designed to preserve the borrower’s ability to make payments on the related indebtedness when due. These provisions include financial and operating covenants, and restrictions on the payments of dividends, the incurrence of indebtedness or the issuance or repurchase of securities by the borrower or any of its subsidiaries. The indenture for the notes will not contain any of these covenants or restrictions or otherwise place any meaningful restrictions on our ability to operate our business as management deems appropriate. As a result, your investment in the notes may not be as protected as an investment in an instrument that contains some or all of these types of covenants and restrictions.

Recent and future regulatory actions and other events may adversely affect the trading price and liquidity of the notes.

We expect that many investors in the notes, including potential purchasers of the notes from investors in this offering, will seek to employ a convertible note arbitrage strategy. Under this strategy, investors typically short sell a certain number of shares of our common stock and adjust their short position over time while they continue to hold the notes. Investors may also implement this type of strategy by entering into swaps on our common stock in lieu of, or in addition to, short selling shares of our common stock.

The SEC and other regulatory authorities have implemented various rules and taken certain actions, and may in the future adopt additional rules and take other actions, that may impact those engaging in short selling activity involving equity securities (including our common stock). These rules and actions include Rule 201 of SEC Regulation SHO, the adoption by the Financial Industry Regulatory Authority, Inc., and the national securities exchanges of a “limit up-limit down” program, the imposition of market-wide circuit breakers that halt trading of securities for certain periods following specific market declines, and the implementation of certain regulatory reforms required by the Dodd-Frank Wall Street Reform and Consumer Protection Act of 2010. Any governmental or regulatory action that restricts investors’ ability to effect short sales of our common stock or enter into equity swaps on our common stock could depress the trading price of, and the liquidity of the market for, the notes.

In addition, the liquidity of the market for our common stock may decline, which could reduce the number of shares available for lending in connection with short sale transactions and the number of counterparties willing to enter into an equity swap on our common stock with a note investor. If investors and potential purchasers seeking to employ a convertible note arbitrage strategy are unable to borrow or enter into equity swaps on our common stock on commercially reasonable terms, then the trading price of, and the liquidity of the market for, the notes may significantly decline.

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You may be subject to tax if we make or fail to make certain adjustments to the conversion rate of the notes even though you do not receive a corresponding cash distribution.

The conversion rate of the notes is subject to adjustment in certain circumstances, including the payment of cash dividends. If the conversion rate is adjusted as a result of a distribution that is taxable to our common stockholders, such as a cash dividend, you will be deemed to have received a distribution, which may be treated as a dividend subject to U.S. federal income tax, without the receipt of any cash. In addition, a failure to adjust (or to adjust adequately) the conversion rate after an event that increases your proportionate interest in us could be treated as a deemed taxable dividend to you. If a make-whole fundamental change occurs prior to the maturity date, under some circumstances, we will increase the conversion rate for notes converted in connection with the make-whole fundamental change. Such increase also may be treated as a distribution subject to U.S. federal income tax as a dividend. See “Certain Material U.S. Federal Income Tax Considerations.” It is unclear whether any such deemed dividend would be eligible for the preferential tax treatment generally available for dividends paid by U.S. corporations to certain non-corporate U.S. holders (as defined under “Certain Material U.S. Federal Income Tax Considerations”). If you are a non-U.S. holder (as defined under “Certain Material U.S. Federal Income Tax Considerations”), any deemed dividend generally will be subject to U.S. federal withholding tax at a 30% rate, or such lower rate as may be specified by an applicable treaty, which may be set off against subsequent payments on the notes or any shares of our common stock owned by you or from any proceeds of any subsequent sale, exchange or other disposition of the notes (including the retirement of a note) or such common stock or other funds or assets of yours. The Internal Revenue Service has proposed regulations addressing the amount and timing of deemed distributions, obligations of withholding agents and filing and notice obligations of issuers, which if adopted could affect the U.S. federal income tax treatment of beneficial owners of notes deemed to receive such a distribution. See “Certain Material U.S. Federal Income Tax Considerations.”

A rating agency may not rate the notes or may assign a rating that is lower than expected.

We do not intend to seek to have the notes rated by any rating agency. However, if one or more rating agencies rates the notes and assigns a rating that is lower than the rating that investors expect, or reduces their rating in the future, then the trading price of our common stock and the notes could significantly decline.

In addition, market perceptions of our creditworthiness will directly affect the trading price of the notes. Accordingly, if a ratings agency rates any of our indebtedness in the future or downgrades or withdraws the rating, or puts us on credit watch, then the trading price of the notes will likely decline.

Provisions in the indenture could delay or prevent an otherwise beneficial takeover of us.

Certain provisions in the notes and the indenture could make a third party attempt to acquire us more difficult or expensive. For example, if a takeover constitutes a fundamental change, then noteholders will have the right to require us to repurchase their notes for cash. In addition, if a takeover constitutes a make-whole fundamental change, then we may be required to temporarily increase the conversion rate. In either case, and in other cases, our obligations under the notes and the indenture could increase the cost of acquiring us or otherwise discourage a third party from acquiring us or removing incumbent management, including in a transaction that noteholders or holders of our common stock may view as favorable.

The capped call transactions may affect the value of the notes and our common stock.

In connection with the pricing of the notes, we entered into a capped call transaction with the capped call counterparty. If the underwriters exercise their over-allotment option, we expect to enter into an additional capped call transaction with the capped call counterparty. The capped call transactions cover, subject to customary adjustments, the number of shares of our common stock initially underlying the notes. The capped call transactions are generally expected to reduce the potential dilution as a result of conversion of the notes and/or offset any cash payments we are required to make in excess of the principal amount of converted notes, as the case may be, with such reduction and/or offset subject to a cap as described under “Description of Capped Call Transactions.”

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In connection with establishing its initial hedge of the capped call transactions, the capped call counterparty or its affiliates expect to purchase shares of our common stock and/or enter into various derivatives with respect to our common stock concurrently with or shortly after the pricing of the notes, including with certain investors in the notes. This activity could increase (or reduce the size of any decrease in) the market price of our common stock or the notes at that time.

In addition, the capped call counterparty or its affiliates may modify their hedge positions by entering into or unwinding various derivatives with respect to our common stock and/or purchasing or selling our common stock or other securities of ours in secondary market transactions following the pricing of the notes and prior to the maturity of the notes (and are likely to do so on each exercise date of the capped call transactions, which are expected to occur during the 60 trading day period beginning on the 61st scheduled trading day prior to the maturity date of the notes, or following any termination of any portion of the capped call transaction in connection with any repurchase, redemption or early conversion of the notes). This activity could also cause or avoid an increase or a decrease in the market price of our common stock or the notes, which could affect your ability to convert the notes and, to the extent the activity occurs during any observation period related to a conversion of notes, it could affect the amount and value of the consideration that you will receive upon conversion of the notes.

In addition, if any such capped call transaction fails to become effective, whether or not this offering of notes is completed, the capped call counterparty or its affiliates may unwind their hedge positions with respect to our common stock, which could adversely affect the value of our common stock and, if the notes have been issued, the value of the notes.

We are subject to counterparty risk with respect to the capped call transactions.

The capped call counterparty to the capped call transactions is a financial institution, and we will be subject to the risk that the capped call counterparty may default or otherwise fail to perform, or may exercise certain rights to terminate, its obligations under the capped call transactions. Our exposure to the credit risk of the capped call counterparty will not be secured by any collateral. If the capped call counterparty becomes subject to insolvency proceedings, we will become an unsecured creditor in those proceedings with a claim equal to our exposure at the time under such transaction. Our exposure will depend on many factors but, generally, our exposure will increase if the market price or the volatility of our common stock increases. In addition, upon a default or other failure to perform, or a termination of obligations, by the capped call counterparty, we may suffer adverse tax consequences and more dilution than we currently anticipate with respect to our common stock. We can provide no assurances as to the financial stability or viability of the capped call counterparty.

You may be unable to convert your notes before July 15, 2026, and the trading price of the notes could be less than the value of the consideration into which they could otherwise be converted.

Before July 15, 2026, you may convert your notes only if specific conditions are met. If these conditions are not met, then you will not be able to convert your notes and receive the cash, shares of our common stock or combination of cash and shares, as applicable, into which the notes would otherwise be convertible. As a result, the notes may trade at prices that are less than the value of the consideration into which they would otherwise be convertible.

Fluctuations in the trading price of our common stock after you elect to convert your notes may cause you to receive less valuable consideration than expected.

We will generally have the right to settle conversions in cash, shares of our common stock or a combination of cash and shares. If we elect to settle conversions solely in cash or in a combination of cash and shares, then the consideration due upon conversion will be determined based on the volume-weighted average price of our

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common stock during the related “observation period,” which is defined under the caption “Description of Notes—Definitions” and will consist of 60 “VWAP trading days.” Except in certain circumstances, the observation period will begin after the related conversion date. Accordingly, a considerable amount of time may lapse between the time you elect to convert your notes and the time you receive the consideration due upon conversion, and if the trading price of our common stock declines during this time, then you may receive less consideration, or consideration that is less valuable, than expected.

Our management may spend the proceeds of this offering in ways with which you may disagree or that may not be profitable.

We intend to use a portion of the net proceeds from this offering, if completed, to pay the cost of the capped call transactions and to fund (i) the continued development of and commercial readiness activities associated with omecamtiv mecarbil, (ii) the continued clinical development of CK-274 and related compounds in indications associated with hypertrophic cardiomyopathies and related diseases associated with diastolic dysfunction and cardiac fibrosis, including heart failure with preserved ejection fraction, (iii) the continued clinical development of reldesemtiv in patients with ALS and SMA, including potential Phase 3 clinical trials and other commercial readiness activities, and (iv) working capital and other general corporate purposes, including tenant improvement of the new facility we plan to move into in 2021, capital expenditures, debt service or retirement of debt, including existing debt outstanding under the Term Loan. However, our management will have broad discretion to apply the net proceeds, and investors will rely on our management’s judgment in spending the net proceeds. Our management may use the proceeds in ways that do not earn a profit or otherwise result in the creation of stockholder value. Pending application of the net proceeds as described above, we intend to invest the net proceeds in a variety of capital-preservation instruments, including direct or guaranteed obligations of the U.S. government, certificates of deposit and money market funds, in accordance with our investment policy.

The accounting method for the notes could adversely affect our reported financial condition and results.

The accounting method for reflecting the notes on our balance sheet, accruing interest expense for the notes and reflecting the underlying shares of our common stock in our reported diluted earnings per share may adversely affect our reported earnings and financial condition.

We expect that, under applicable accounting principles, the initial liability carrying amount of the notes will be the fair value of a similar debt instrument that does not have a conversion feature, valued using our cost of capital for straight, unconvertible debt. We expect to reflect the difference between the net proceeds from this offering and the initial carrying amount as a debt discount for accounting purposes, which will be amortized into interest expense over the term of the notes. As a result of this amortization, the interest expense that we expect to recognize for the notes for accounting purposes will be greater than the cash interest payments we will pay on the notes, which will result in lower reported net income. The lower reported income resulting from this accounting treatment could depress the trading price of our common stock and the notes.

In addition, under certain circumstances we may be eligible to use the treasury stock method to reflect the shares underlying the notes in our diluted earnings per share. Under this method, if the conversion value of the notes exceeds their principal amount for a reporting period, then we will calculate our diluted earnings per share assuming that all the notes were converted and that we issued shares of our common stock to settle the excess. However, if reflecting the notes in diluted earnings per share in this manner is anti- dilutive, or if the conversion value of the notes does not exceed their principal amount for a reporting period, then the shares underlying the notes will not be reflected in our diluted earnings per share. In addition, if accounting standards change in the future and we are not permitted to use the treasury stock method, then our diluted earnings per share may decline. For example, in July 2019, the Financial Accounting Standards Board published an exposure draft proposing to amend these accounting standards to eliminate the treasury stock method for convertible instruments and instead require application of the “if-converted” method. Under that method, if it is adopted, diluted earnings per share

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would generally be calculated assuming that all the notes were converted solely into shares of common stock at the beginning of the reporting period, unless the result would be anti-dilutive. The application of the if-converted method may reduce our reported diluted earnings per share.

Furthermore, if any of the conditions to the convertibility of the notes is satisfied, then we may be required under applicable accounting standards to reclassify the liability carrying value of the notes as a current, rather than a long-term, liability. This reclassification could be required even if no noteholders convert their notes and could materially reduce our reported working capital.

Because the notes will initially be held in book-entry form, noteholders must rely on DTC’s procedures to receive communications relating to the notes and exercise their rights and remedies.

We will initially issue the notes in the form of one or more “global notes” registered in the name of Cede & Co., as nominee of DTC. Beneficial interests in global notes will be shown on, and transfers of global notes will be effected only through, the records maintained by DTC. Except in limited circumstances, we will not issue certificated notes. See “Description of Notes—Book Entry, Settlement and Clearance.” Accordingly, if you own a beneficial interest in a global note, then you will not be considered an owner or holder of the notes. Instead, DTC or its nominee will be the sole holder of the notes. Payments of principal, interest and other amounts on global notes will be made to the paying agent, who will remit the payments to DTC. We expect that DTC will then credit those payments to the DTC participant accounts that hold book-entry interests in the global notes and that those participants will credit the payments to indirect DTC participants. Unlike persons who have certificated notes registered in their names, owners of beneficial interests in global notes will not have the direct right to act on our solicitations for consents or requests for waivers or other actions from noteholders. Instead, those beneficial owners will be permitted to act only to the extent that they have received appropriate proxies to do so from DTC or, if applicable, a DTC participant. The applicable procedures for the granting of these proxies may not be sufficient to enable owners of beneficial interests in global notes to vote on any requested actions on a timely basis. In addition, notices and other communications relating to the notes (including any notice of redemption) will be sent to DTC. We expect DTC will forward any such communications to DTC participants, which in turn would forward such communications to indirect DTC participants, but we can make no assurances that you will timely receive any such communications.

Holding notes will not, in itself, confer any rights with respect to our common stock.

Noteholders will generally not be entitled to any rights with respect to our common stock (including voting rights and rights to receive any dividends or other distributions on our common stock). However, noteholders will be subject to all changes affecting our common stock to the extent the trading price of the notes depends on the market price of our common stock and to the extent they receive shares of our common stock upon conversion of their notes. For example, if we propose an amendment to our charter documents that requires stockholder approval, then a noteholder will not, as such, be entitled to vote on the amendment, although the noteholder will be subject to any changes implemented by that amendment in the powers, preferences or special rights of our common stock.

Risks Related to Our Business

We have a history of significant losses and may not achieve or sustain profitability and, as a result, you may lose part or all of your investment.

We have generally incurred operating losses in each year since our inception in 1997, due to costs incurred in connection with our research and development activities and general and administrative costs associated with our operations. Our drug candidates are all in early through late-stage clinical testing, and we and our partners must conduct significant additional clinical trials before we and our partners can seek the regulatory approvals necessary to begin commercial sales of our drugs. We expect to incur increasing losses for at least several more

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years, as we continue our research activities and conduct development of, and seek regulatory approvals for, our drug candidates, and commercialize any approved drugs. If our drug candidates fail or do not gain regulatory approval, or if our drugs do not achieve market acceptance, we will not be profitable. If we fail to become and remain profitable, or if we are unable to fund our continuing losses, you could lose part or all of your investment.

We will need substantial additional capital in the future to sufficiently fund our operations.

We have consumed substantial amounts of capital to date, and our operating expenditures will increase over the next several years if we expand our research and development activities. We have funded our operations and capital expenditures with proceeds primarily from private and public sales of our equity securities, a royalty monetization agreement, strategic alliances, long-term debt, other financings, interest on investments and grants. We believe that our existing cash and cash equivalents, short-term investments and interest earned on investments should be sufficient to meet our projected operating requirements for at least the next 12 months. We have based this estimate on assumptions that may prove to be wrong, and we could utilize our available capital resources sooner than we currently expect. Because of the numerous risks and uncertainties associated with the development of our drug candidates and other research and development activities, including risks and uncertainties that could impact the rate of progress of our development activities, we are unable to estimate with certainty the amounts of capital outlays and operating expenditures associated with these activities.

For the foreseeable future, our operations will require significant additional funding, in large part due to our research and development expenses and the absence of any revenues from product sales. For example, we will require significant additional funding to enable us to conduct further development of our product candidates. Until we can generate a sufficient amount of product revenue, we expect to raise future capital through strategic alliance and licensing arrangements, public or private equity offerings and debt financings. We do not currently have any commitments for future funding other than reimbursements, milestone and royalty payments that we may receive under our collaboration agreements with Amgen and Astellas. We may not receive any further funds under those agreements. Our ability to raise funds may be adversely impacted by current economic conditions. As a result of these and other factors, we do not know whether additional financing will be available when needed, or that, if available, such financing would be on terms favorable to our stockholders or us.

To the extent that we raise additional funds through strategic alliances or licensing or other arrangements with third parties, we will likely have to relinquish valuable rights to our technologies, research programs or drug candidates, or grant licenses on terms that may not be favorable to us. To the extent that we raise additional funds by issuing equity securities, our stockholders will experience additional dilution and our share price may decline. To the extent that we raise additional funds through debt financing, the financing may involve covenants that restrict our business activities. In addition, funding from any of these sources, if needed, may not be available to us on favorable terms, or at all, or in accordance with our planned timelines.

If we cannot raise the funds we need to operate our business, we will need to delay or discontinue certain research and development activities, and our stock price may be negatively affected.

We are obligated to develop and maintain proper and effective internal control over financial reporting. In February 2019, our management identified a material weakness in our internal control over financial reporting. If we are unable to remediate the material weakness or other control deficiencies are identified, we may not be able to report our financial results accurately, prevent fraud or file our periodic reports in a timely manner, which may adversely affect investor confidence in our company and, as a result, the value of our common stock.

We are required, pursuant to Section 404 of the Sarbanes-Oxley Act, to furnish a report by management on, among other things, the effectiveness of our internal control over financial reporting.

Complying with Section 404 requires a rigorous compliance program as well as adequate time and resources. We may not be able to complete our internal control evaluation, testing and any required remediation

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in a timely fashion. Additionally, if we identify one or more material weaknesses in our internal control over financial reporting, we will not be able to assert that our internal controls are effective. A material weakness is a deficiency, or combination of deficiencies, in internal control over financial reporting such that there is a reasonable possibility that a material misstatement of our annual or interim financial statements will not be prevented or detected on a timely basis. On February 27, 2019, our management concluded that our internal controls over financial reporting were ineffective as of December 31, 2018 due to the identification of a material weakness. As of December 31, 2018, we identified a material weakness related to the ineffective review and verification of internally prepared reports and analyses utilized in our financial statement closing process. The material weakness related to employee turnover resulting in a temporary lack of resources in financial reporting roles with the appropriate skills to perform effective review during our financial statement close process. This material weakness did not result in the restatement of prior quarterly or annually filed financial statements. To remediate the material weakness described above, we have filled certain positions within the accounting department and will, as necessary, supplement any further staffing needs with temporary resources. We will also continue to evaluate and improve our internal controls, processes and procedures in the financial statement close process.

We also previously concluded that our internal controls over financial reporting were not effective as of September 30, 2016, because a material weakness existed in our internal control over financial reporting related to research and development expenses associated with the review of clinical trial expenses incurred under our clinical research organization trial agreements, including in part, our review of information received from third-party service providers that is used in the operation of this control. We remediated this material weakness as of December 31, 2016.

We cannot be certain that these measures will successfully remediate the material weakness identified in connection with the audit of our financial statements for the year ended December 31, 2018 and that other material weaknesses and control deficiencies will not be discovered in the future. If our efforts are not successful or other material weaknesses are identified in the future or we are not able to comply with the requirements of Section 404 in a timely manner, our reported financial results could be materially misstated, we would receive an adverse opinion regarding our internal controls over financial reporting from our independent registered public accounting firm, and we could be subject to investigations or sanctions by regulatory authorities, which would require additional financial and management resources, and the value of our common stock could decline. In addition, because we concluded that our internal controls over financial reporting were not effective as of December 31, 2018 and as of September 30, 2016, and to the extent we identify future weaknesses or deficiencies, there could be material misstatements in our consolidated financial statements and we could fail to meet our financial reporting obligations. As a result, our ability to obtain additional financing, or obtain additional financing on favorable terms, could be materially and adversely affected which, in turn, could materially and adversely affect our business, our financial condition and the value of our common stock. If we are unable to assert that our internal control over financial reporting is effective in the future, or if our independent registered public accounting firm is unable to express an opinion or expresses an adverse opinion on the effectiveness of our internal controls in the future, investor confidence in the accuracy and completeness of our financial reports could be further eroded, which would have a material adverse effect on the price of our common stock.

Covenants in the loan agreement governing the Term Loan restrict our business and operations in many ways and if we do not effectively manage our covenants, our financial conditions and results of operations could be adversely affected. Our operations may not provide sufficient cash to meet the repayment obligations of our debt incurred under such loan agreement.

The loan agreement governing the Term Loan requires that we comply with certain covenants applicable to us, including among other things, covenants restricting dispositions, changes in business, management, ownership or business locations, mergers or acquisitions, indebtedness, encumbrances, distributions, investments, transactions with affiliates and subordinated debt, any of which could restrict our business and operations,

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particularly our ability to respond to changes in our business or to take specified actions to take advantage of certain business opportunities that may be presented to us. Our failure to comply with any of the covenants could result in a default under the Term Loan, which could permit the lenders to declare all or part of any outstanding borrowings to be immediately due and payable.

If we are unable to repay those amounts, the Term Loan lenders could proceed against the collateral granted to them to secure that debt, which would seriously harm our business. In addition, should we be unable to comply with these covenants or if we default on any portion of our outstanding borrowings, the lenders can also impose a 5.0% penalty. In addition, the Term Loan has interest-only payments through December 31, 2020. The interest-only period may be extended upon the achievement of certain development milestones. If we do not achieve some or all of these development milestones, our liquidity and cash position may be harmed.

We have never generated, and may never generate, revenues from commercial sales of our drugs and we will not have drugs to market for at least several years, if ever.

We currently have no drugs for sale and we cannot guarantee that we will ever develop or obtain approval to market any drugs. To receive marketing approval for any drug candidate, we must demonstrate that the drug candidate satisfies rigorous standards of safety and efficacy to the FDA in the United States and other regulatory authorities abroad. We and our partners will need to conduct significant additional research and preclinical and clinical testing before we or our partners can file applications with the FDA or other regulatory authorities for approval of any of our drug candidates. In addition, to compete effectively, our drugs must be easy to use, cost-effective, covered by insurance or government sponsored medical plans, and economical to manufacture on a commercial scale, compared to other therapies available for the treatment of the same conditions. We may not achieve any of these objectives. Currently, our drug candidates in clinical development include omecamtiv mecarbil for the potential treatment of heart failure and reldesemtiv for the potential treatment of SMA, ALS and potentially other neuromuscular and non-neuromuscular indications associated with muscle weakness. We cannot be certain that the clinical development of our current or any future drug candidates will be successful, that they will receive the regulatory approvals required to commercialize them, that they will ultimately be accepted by prescribers or reimbursed by insurers or that any of our other research programs will yield a drug candidate suitable for clinical testing or commercialization. Our commercial revenues, if any, will be derived from sales of drugs that we do not expect to be commercially marketed for at least several years, if at all. The development of any one or all of these drug candidates may be discontinued at any stage of our clinical trials programs and we may not generate revenue from any of these drug candidates.

Clinical trials may fail to demonstrate the desired safety and efficacy of our drug candidates, which could prevent or significantly delay completion of clinical development and regulatory approval.

Prior to receiving approval to commercialize any of our drug candidates, we or our partners must adequately demonstrate to the satisfaction of FDA and foreign regulatory authorities that the drug candidate is sufficiently safe and effective with substantial evidence from well-controlled clinical trials. We or our partners will need to demonstrate efficacy in clinical trials for the treatment of specific indications and monitor safety throughout the clinical development process and following approval. None of our drug candidates have yet met the safety and efficacy standards required for regulatory approval for commercialization and they may never do so. In addition, for each of our preclinical compounds, we or our partners must adequately demonstrate satisfactory chemistry, formulation, quality, stability and toxicity in order to submit an IND to the FDA, or an equivalent application in foreign jurisdictions, that would allow us to advance that compound into clinical trials. Furthermore, we or our partners may need to submit separate INDs (or foreign equivalent) to different divisions within the FDA (or foreign regulatory authorities) in order to pursue clinical trials in different therapeutic areas. Each new IND (or foreign equivalent) must be reviewed by the new regulatory division before the clinical trial under its jurisdiction can proceed, entailing all the risks of delay inherent to regulatory review. If our or our partners’ current or future preclinical studies or clinical trials are unsuccessful, our business will be significantly harmed and our stock price could be negatively affected.

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All of our drug candidates are prone to the risks of failure inherent in drug development. Preclinical studies may not yield results that would adequately support the filing of an IND (or a foreign equivalent) with respect to our potential drug candidates. Even if the results of preclinical studies for a drug candidate are sufficient to support such a filing, the results of preclinical studies do not necessarily predict the results of clinical trials. As an example, because the physiology of animal species used in preclinical studies may vary substantially from other animal species and from humans, it may be difficult to assess with certainty whether a finding from a study in a particular animal species will result in similar findings in other animal species or in humans. For any of our drug candidates, the results from Phase 1 clinical trials in healthy volunteers and clinical results from Phase 1 and 2 trials in patients are not necessarily indicative of the results of later and larger clinical trials that are necessary to establish whether the drug candidate is safe and effective for the applicable indication. Likewise, interim results from a clinical trial may not be indicative of the final results from that trial, and results from early Phase 2 clinical trials may not be indicative of the results from later clinical trials. For example, early Phase 2 clinical trials of tirasemtiv in patients with ALS showed encouraging dose-related trends in measurements of the ALSFRS-R, a clinically validated instrument designed to measure disease progression and changes in functional status, for patients receiving tirasemtiv compared to those receiving placebo. However, BENEFIT-ALS, a Phase 2b clinical trial of tirasemtiv in patients with ALS, did not achieve its primary efficacy endpoint, the mean change from baseline in the ALSFRS-R for patients receiving tirasemtiv compared to those receiving placebo, and in November 2017, we announced that VITALITY-ALS did not achieve its primary endpoint or secondary endpoints. Following the results of VITALITY-ALS, we suspended development of tirasemtiv.

Moreover, the Phase 2 clinical trial of reldesemtiv in COPD and Phase 1b clinical trial of reldesemtiv in elderly subjects with limited mobility did not show efficacy, and there can be no assurance that reldesemtiv will demonstrate efficacy in other indications, regardless of the phase of development.

In addition, while the clinical trials of our drug candidates are designed based on the available relevant information, such information may not accurately predict what actually occurs during the course of the trial itself, which may have consequences for the conduct of an ongoing clinical trial or for the eventual results of that trial. For example, the number of patients planned to be enrolled in a placebo-controlled clinical trial is determined in part by estimates relating to expected treatment effect and variability about the primary endpoint. These estimates are based upon earlier non-clinical and clinical studies of the drug candidate itself and clinical trials of other drugs thought to have similar effects in a similar patient population. If information gained during the conduct of the trial shows these estimates to be inaccurate, we may elect to adjust the enrollment accordingly, which may cause delays in completing the trial, additional expense or a statistical penalty to apply to the evaluation of the trial results.

Furthermore, in view of the uncertainties inherent in drug development, such clinical trials may not be designed with focus on indications, patient populations, dosing regimens, endpoints, safety, efficacy or pharmacokinetic parameters or other variables that will provide the necessary safety or efficacy data to support regulatory approval to commercialize the resulting drugs. For example, we believe that effects on respiratory function, including SVC, may be appropriate as a clinical endpoint for reldesemtiv; however, regulatory authorities may not accept these effects as a clinical endpoint to support registration of reldesemtiv for the treatment of ALS. Clinical trials of our drug candidates are designed based on guidance or advice from regulatory agencies, which is subject to change during the development of the drug candidate at any time. Such a change in a regulatory agency’s guidance or advice may cause that agency to deem results from trials to be insufficient to support approval of the drug candidate and require further clinical trials of that drug candidate to be conducted. In addition, individual patient responses to the dose administered of a drug may vary in a manner that is difficult to predict. Also, the methods we select to assess particular safety, efficacy or pharmacokinetic parameters may not yield the same statistical precision in estimating our drug candidates’ effects as may other methodologies. Even if we believe the data collected from clinical trials of our drug candidates are promising, these data may not be sufficient to support approval by the FDA or foreign regulatory authorities. Non-clinical and clinical data can be interpreted in different ways. Accordingly, the FDA or foreign regulatory authorities

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could interpret these data in different ways from us or our partners, which could delay, limit or prevent regulatory approval.

Furthermore, while planned interim analyses in clinical trials can enable early terminations for futility or for overwhelming efficacy, the timing, which can be based on accrual of events, enrollment or other factors, and the results of such analyses, is unpredictable. For example, in GALACTIC-HF, a Phase 3 clinical trial of omecamtiv mecarbil, a second interim analysis for superiority and futility is planned to be conducted in the first half of 2020, but the exact timing and outcome of such interim analysis are uncertain. Our GALACTIC-HF trial is being conducted under an SPA agreement with FDA. However, even where the FDA agrees to the design, execution and analysis proposed in protocols reviewed under the SPA process, the FDA may revoke or alter its agreement in certain circumstances, and the FDA retains significant latitude and discretion in interpreting the terms of the SPA agreement and the data and results from any study that is subject to the SPA agreement. There, is no guarantee that either the trial will be successful, or even if successful, that FDA would approve any resulting NDA.

Administering any of our drug candidates or potential drug candidates may produce undesirable side effects, also known as adverse events. Toxicities and adverse events observed in preclinical studies for some compounds in a particular research and development program may also occur in preclinical studies or clinical trials of other compounds from the same program. Potential toxicity issues may arise from the effects of the active pharmaceutical ingredient itself or from impurities or degradants that are present in the active pharmaceutical ingredient or could form over time in the formulated drug candidate or the active pharmaceutical ingredient. These toxicities or adverse events could delay or prevent the filing of an IND (or a foreign equivalent) with respect to our drug candidates or potential drug candidates or cause us, our partners or the FDA or foreign regulatory authorities to modify, suspend or terminate clinical trials with respect to any drug candidate at any time during the development program. Further, the administration of two or more drugs contemporaneously can lead to interactions between them, and our drug candidates may interact with other drugs that trial subjects are taking. If the adverse events are severe or frequent enough to outweigh the potential efficacy of a drug candidate, the FDA or other regulatory authorities could deny approval of that drug candidate for any or all targeted indications. Even if one or more of our drug candidates were approved for sale as drugs, the occurrence of even a limited number of adverse events or toxicities when used in large populations may cause the FDA or foreign regulatory authorities to impose restrictions on, or stop, the further marketing of those drugs. Indications of potential adverse events or toxicities which do not seem significant during the course of clinical trials may later turn out to actually constitute serious adverse events or toxicities when a drug is used in large populations or for extended periods of time.

We have observed certain adverse events in the clinical trials conducted with our drug candidates. For example, in clinical trials of omecamtiv mecarbil, adverse events of chest discomfort, palpitations, dizziness and feeling hot, increases in heart rate, declines in blood pressure, electrocardiographic changes consistent with acute myocardial ischemia and transient rises in the MB fraction of creatine kinase and cardiac troponins I and T, which are indicative of myocardial infarction were observed during treatment with omecamtiv mecarbil.

In addition, clinical trials of reldesemtiv and omecamtiv mecarbil enroll patients who typically suffer from serious diseases which put them at increased risk of death. These patients may die while receiving our drug candidates. In such circumstances, it may not be possible to exclude with certainty a causal relationship to our drug candidate, even though the responsible clinical investigator may view such an event as not study drug-related.

Any failure or significant delay in completing preclinical studies or clinical trials for our drug candidates, or in receiving and maintaining regulatory approval for the sale of any resulting drugs, may significantly harm our business and negatively affect our stock price.

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The failure of a number of Phase 3 clinical trials evaluating other compounds as potential treatments for patients with ALS may suggest an increased risk that our clinical development program of reldesemtiv in patients with ALS will also fail.

In recent years, a number of Phase 3 clinical trials of potential treatments for ALS have failed to demonstrate the requisite efficacy for regulatory approval or for their continued development. These include our trial of tirasemtiv known as VITALITY-ALS, Biogen’s trial of dexpramipexole, known as EMPOWER, the National Institute of Neurological Disorders and Stroke’s trial of ceftriaxone, and Trophos SA’s trial of olesoxime. Reldesemtiv, like these compounds, may fail in clinical development if it does not show a statistically significant level of clinical efficacy or if the adverse event profile is too great compared to its benefits. Further, even if we believe the data collected from the planned clinical development program of reldesemtiv are promising and should support approval, the FDA or other regulatory authorities may not deem these data to be sufficient to support approval.

Clinical trials are expensive, time-consuming and subject to delay.

Clinical trials are subject to rigorous regulatory requirements and are very expensive, difficult and time-consuming to design and implement. The length of time and number of trial sites and patients required for clinical trials vary substantially based on the type, complexity, novelty, intended use of the drug candidate and safety concerns. Clinical trials of our current drug candidates can each continue for several more years. However, the clinical trials for all or any of our drug candidates may take significantly longer to complete. The commencement and completion of our or our partners’ clinical trials could be delayed or prevented by many factors, including, but not limited to:

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We do not know whether planned clinical trials will begin on time, or whether planned or currently ongoing clinical trials will need to be restructured or will be completed on schedule, if at all. Significant delays in clinical trials will impede our ability to commercialize our drug candidates and generate revenue and could significantly increase our development costs.

If we encounter difficulties enrolling patients in our clinical trials, our clinical development activities could be delayed or otherwise adversely affected.

The timely completion of clinical trials in accordance with their protocols depends, among other things, on our ability to enroll a sufficient number of patients who remain in the trial until its conclusion. We may experience difficulties in patient enrollment in clinical trials for a variety of reasons. The enrollment of patients depends on many factors, including:

In addition, our and our partners’ clinical trials will compete with other clinical trials for product candidates that are in the same therapeutic areas as our and our partners’ product candidates, and this competition will reduce the number and types of patients available to us, because some patients who might have opted to enroll in our or our partners’ trials may instead opt to enroll in a trial being conducted by one of our competitors. Since the number of qualified clinical investigators is limited, we expect to conduct some of our or our partners’ clinical trials at the same clinical trial sites that some of our competitors use, which will reduce the number of patients who are available for our clinical trials in such clinical trial site.

Delays in patient enrollment may result in increased costs or may affect the timing or outcome of the planned clinical trials, which could prevent completion of these trials and adversely affect our and our partners’ ability to advance the development of product candidates.

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We depend on Amgen for the conduct and funding of the development and commercialization of omecamtiv mecarbil.

Under our strategic alliance, Amgen holds an exclusive worldwide license to our drug candidate omecamtiv mecarbil. As a result, Amgen is responsible for the development and obtaining and maintaining regulatory approval of omecamtiv mecarbil for the potential treatment of heart failure worldwide.

Amgen is conducting GALACTIC-HF, a Phase 3 clinical trial of omecamtiv mecarbil. We do not control the development activities being conducted or that may be conducted in the future by Amgen, including, but not limited to, the timing of initiation, termination or completion of clinical trials, the analysis of data arising out of those clinical trials or the timing of release of data concerning those clinical trials, which may impact our ability to report on Amgen’s results. Amgen may conduct these activities more slowly or in a different manner than we would if we controlled the development of omecamtiv mecarbil. Amgen is responsible for submitting future applications to the FDA and other regulatory authorities for approval of omecamtiv mecarbil and will be the owner of marketing approvals issued by the FDA and other regulatory authorities for omecamtiv mecarbil, subject to Servier’s exclusive rights for the commercialization of omecamtiv mecarbil in Europe, as well as the CIS, including Russia. If the FDA or other regulatory authorities approve omecamtiv mecarbil, Amgen will also be responsible for the marketing and sale of the resulting drug, subject to our right to co-promote omecamtiv mecarbil in North America in connection with the exercise of our option to co-fund Phase 3 development costs of omecamtiv mecarbil under the collaboration and subject to Servier’s exclusive rights for the commercialization of omecamtiv mecarbil in Europe, as well as the CIS, including Russia. However, we cannot control whether Amgen will devote sufficient attention and resources to the development of omecamtiv mecarbil or will proceed in an expeditious manner, even with our exercise of our option and co-funding of the Phase 3 development program of omecamtiv mecarbil. Even if the FDA or other regulatory agencies approve omecamtiv mecarbil, Amgen or Servier may elect not to proceed with the commercialization of the resulting drug in one or more countries.

Disputes may arise between us and Amgen, which may delay or cause the termination of any clinical trials of omecamtiv mecarbil, result in significant litigation or cause Amgen to act in a manner that is not in our best interest. The costs associated with the continuing development of omecamtiv mecarbil may cause Amgen to reconsider the terms of its investment and seek to amend or terminate our collaboration agreement or to suspend the development of omecamtiv mecarbil. If development of omecamtiv mecarbil does not progress for these or any other reasons, we would not receive further milestone payments or royalties on product sales from Amgen with respect to omecamtiv mecarbil. If the results of one or more clinical trials with omecamtiv mecarbil do not meet Amgen’s expectations at any time, Amgen may elect to terminate further development of omecamtiv mecarbil or certain of the potential clinical trials for omecamtiv mecarbil, even if the actual number of patients treated at that time is relatively small. In addition, Amgen generally has discretion to elect whether to pursue or abandon the development of omecamtiv mecarbil and may terminate our strategic alliance for any reason upon six months prior notice. With our consent, Amgen granted Servier an option to commercialize omecamtiv mecarbil in Europe and the CIS, including Russia, which Servier decided to exercise. In August 2016, we entered into a letter agreement with Amgen and Servier, which provides that if Amgen’s rights to omecamtiv mecarbil are terminated with respect to the territory subject to Servier’s sublicense, the sublicensed rights previously granted by Amgen to Servier with respect to omecamtiv mecarbil will remain in effect and become a direct license or sublicense of such rights by us to Servier, on substantially the same terms as those in the Option, License and Collaboration Agreement between Amgen and Servier. If Amgen abandons omecamtiv mecarbil, it would result in a delay in or could prevent us from commercializing omecamtiv mecarbil and would delay and could prevent us from obtaining revenues for this drug candidate. In addition, we would be required to provide Servier with a direct license or sublicense and the rights to commercialize omecamtiv mecarbil in Europe and the CIS, including Russia, on terms that were not negotiated by us. There can be no assurance that we would be able to negotiate and enter into a definitive agreement with Servier on terms favorable or acceptable to us, or at all.

If Amgen abandons development of omecamtiv mecarbil prior to regulatory approval or if it elects not to proceed with commercialization of the resulting drug following regulatory approval, we would have to seek a

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new partner for development or commercialization, curtail or abandon that development or commercialization, or undertake and fund the development of omecamtiv mecarbil or commercialization of the resulting drug ourselves. If we seek a new partner but are unable to do so on acceptable terms, or at all, or do not have sufficient funds to conduct the development or commercialization of omecamtiv mecarbil ourselves, we would have to curtail or abandon that development or commercialization, which could harm our business.

We depend on Astellas for the conduct and funding of the development and commercialization of reldesemtiv.

The primary objective of our strategic alliance with Astellas is to advance skeletal muscle activators including reldesemtiv as novel therapies for indications associated with muscle weakness.

Astellas has an exclusive license to co-develop and commercialize reldesemtiv for potential application in certain neuromuscular and non-neuromuscular indications worldwide, subject to certain Cytokinetics’ development and commercialization rights. Under this strategic alliance, we have conducted Phase 2 clinical trials of reldesemtiv in patients with SMA and ALS and Astellas has conducted a Phase 2 clinical trial of reldesemtiv in patients with COPD and a Phase 1b clinical trial of reldesemtiv in elderly subjects with limited mobility.

Astellas is currently primarily responsible for the development of reldesemtiv. We do not control the development activities that may be conducted by Astellas, including, but not limited to, the timing of initiation, termination or completion of clinical trials, the analysis of data arising out of those clinical trials or the timing of release of data concerning those clinical trials, which may impact our ability to report on Astellas’ results. Astellas may conduct these activities more slowly or in a different manner than we would. In general, Astellas is responsible for submitting future applications to the FDA or other regulatory authorities for approval of reldesemtiv and will be the owner of any marketing approvals issued by the FDA or other regulatory authorities for reldesemtiv. If the FDA or other regulatory authorities approve reldesemtiv, Astellas will also be responsible for the marketing and sale of the resulting drug, subject to our right to co-promote the drug in the United States, Canada and, for neuromuscular indications, Europe. However, we cannot control whether Astellas will devote sufficient attention and resources to the development of reldesemtiv or will proceed in an expeditious manner. Even if the FDA or other regulatory agencies approve reldesemtiv, Astellas may elect not to proceed with the commercialization of the resulting drug in one or more countries.

If the results of one or more clinical trials with reldesemtiv, including the Phase 2 clinical trials of reldesemtiv in patients with ALS and SMA, do not meet Astellas’ expectations at any time, Astellas may elect to terminate further development of reldesemtiv or certain of the potential clinical trials for reldesemtiv, even if the actual number of patients treated at that time is relatively small. In addition, Astellas generally has discretion to elect whether to pursue or abandon the development of reldesemtiv. Cytokinetics and Astellas have agreed in principle to revise the terms of the collaboration to provide that Cytokinetics will obtain exclusive control over the development and commercialization of FSTAs, including reldesemtiv and CK-601, which would lead to a reduction in the level of funding from Astellas and an associated increase in the share of commercial returns for Cytokinetics. Astellas may terminate our strategic alliance in whole or in part for any reason upon six months prior notice at any time following expiration of the strategic alliance’s research term, which is currently set to expire on December 31, 2019 although we have an agreement in principle with Astellas to extend the research term through December 31, 2020. Disputes may arise between us and Astellas, which may delay or cause the termination of any clinical trials of reldesemtiv, result in significant litigation or cause Astellas to act in a manner that is not in our best interest. If development of reldesemtiv does not progress for these or any other reasons, we would not receive further milestone payments or royalties on product sales from Astellas with respect to reldesemtiv. If Astellas abandons development of reldesemtiv prior to regulatory approval or if it elects not to proceed with commercialization of the resulting drug following regulatory approval, we would have to seek a new partner for development or commercialization, curtail or abandon that development or commercialization, or undertake and fund the development of reldesemtiv or commercialization of the resulting drug ourselves. If we

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seek a new partner but are unable to do so on acceptable terms, or at all, or do not have sufficient funds to conduct the development or commercialization of reldesemtiv ourselves, we would have to curtail or abandon that development or commercialization, which could harm our business.

If we do not enter into strategic alliances for our unpartnered drug candidates or research and development programs or fail to successfully maintain our current or future strategic alliances, we may have to reduce, delay or discontinue our advancement of our drug candidates and programs or expand our research and development capabilities and increase our expenditures.

Drug development is complicated and expensive. We currently have limited financial and operational resources to carry out drug development. Our strategy for developing, manufacturing and commercializing our drug candidates currently requires us to enter into and successfully maintain strategic alliances with pharmaceutical companies or other industry participants to advance our programs and reduce our expenditures on each program. Accordingly, the success of our development activities depends in large part on our current and future strategic partners’ performance, over which we have little or no control.

Our ability to commercialize drugs that we develop with our partners and that generate royalties from product sales depends on our partners’ abilities to assist us in establishing the safety and efficacy of our drug candidates, obtaining and maintaining regulatory approvals and achieving market acceptance of the drugs once commercialized. Our partners may elect to delay or terminate development of one or more drug candidates, independently develop drugs that could compete with ours or fail to commit sufficient resources to the marketing and distribution of drugs developed through their strategic alliances with us. Our partners may not proceed with the development and commercialization of our drug candidates with the same degree of urgency as we would because of other priorities they face. In addition, new business combinations or changes in a partner’s business strategy may adversely affect its willingness or ability to carry out its obligations under a strategic alliance.

If we are not able to successfully maintain our existing strategic alliances or establish and successfully maintain additional strategic alliances, we will have to limit the size or scope of, or delay or discontinue, one or more of our drug development programs or research programs, or undertake and fund these programs ourselves. Alternatively, if we elect to continue to conduct any of these drug development programs or research programs on our own, we will need to expand our capability to conduct clinical development by bringing additional skills, technical expertise and resources into our organization. This would require significant additional funding, which may not be available to us on acceptable terms, or at all.

To the extent we elect to fund the development of a drug candidate, or the commercialization of a drug at our expense, we will need substantial additional funding.

The discovery, development and commercialization of new drugs is costly. As a result, to the extent we elect to fund the development of a drug candidate or the commercialization of a drug, we will need to raise additional capital to:

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Our future funding requirements will depend on many factors, including, but not limited to:

Until we can generate a sufficient amount of product revenue to finance our cash requirements, which we may never do, we expect to continue to finance our future cash needs primarily through strategic alliances and other financings. We cannot be certain that additional funding will be available on acceptable terms, or at all. If we are not able to secure additional funding when needed, we may have to delay, reduce the scope of or eliminate one or more of our clinical trials or research and development programs or future commercialization initiatives.

We depend on contract research organizations, or CROs, to conduct our clinical trials and have limited control over their performance. If these CROs do not successfully carry out their contractual duties or meet expected deadlines, or if we lose any of our CROs, we may not be able to obtain regulatory approval for or commercialize our product candidates on a timely basis, if at all.

We have used and intend to continue to use a limited number of CROs within and outside of the United States to conduct clinical trials of our drug candidates and related activities. We do not have control over many aspects of our CROs’ activities, and cannot fully control the amount, timing or quality of resources that they devote to our programs. CROs may not assign as high a priority to our programs or pursue them as diligently as we would if we were undertaking these programs ourselves. The activities conducted by our CROs therefore may not be completed on schedule or in a satisfactory manner. CROs may also give higher priority to relationships with our competitors and potential competitors than to their relationships with us. Outside of the United States, we are particularly dependent on our CROs’ expertise in communicating with clinical trial sites and regulatory authorities and ensuring that our clinical trials and related activities and regulatory filings comply with applicable laws.

Our CROs’ failure to carry out development activities on our behalf as agreed and in accordance with our and the FDA’s or other regulatory agencies’ requirements and applicable U.S. and foreign laws, or our failure to properly coordinate and manage these activities, could increase the cost of our operations and delay or prevent the development, approval and commercialization of our drug candidates. For example, in June 2013, we learned from our data management vendor for BENEFIT-ALS that a programming error in the electronic data capture system controlling study drug assignment caused 58 patients initially randomized to and treated with tirasemtiv to receive placebo instead at a certain trial visit and for the remainder of the trial. In order to maintain the originally intended statistical power of the trial, we amended the protocol to permit enrollment of approximately 680 patients, or 180 patients in addition to the 500 patients allowed under the existing protocol. This protocol amendment resulted in additional costs and delays in conducting BENEFIT-ALS. Further, for the quarter ended September 30, 2016, we determined that there was an error in the accounting for the recognition of clinical research and development expenses related to the information received from one of our CROs, which resulted in a restatement of our clinical research and development expenses, related clinical accrual accounts and related

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financial disclosures as of and for the three and nine month periods ended September 30, 2016. In addition, if a CRO fails to perform as agreed, our ability to collect damages may be contractually limited. If we fail to effectively manage the CROs carrying out the development of our drug candidates or if our CROs fail to perform as agreed, the commercialization of our drug candidates will be delayed or prevented. In many cases, our CROs have the right to terminate their agreements with us in the event of an uncured material breach. Identifying, qualifying and managing performance of third-party service providers can be difficult, time consuming and cause delays in our development programs. In addition, there is a natural transition period when a new CRO commences work and the new CRO may not provide the same type or level of services as the original provider. If any of our relationships with our third-party CROs terminate, we may not be able to enter into arrangements with alternative CROs or to do so timely or on commercially reasonable terms.

We have no manufacturing capacity and depend on our strategic partners and contract manufacturers to produce our clinical trial materials, including our drug candidates, and anticipate continued reliance on contract manufacturers for the development and commercialization of our potential drugs.

We do not currently operate manufacturing facilities for clinical or commercial production of our drug candidates. We have limited experience in drug formulation and manufacturing, and we lack the resources and the capabilities to manufacture any of our drug candidates on a clinical or commercial scale. Amgen has assumed responsibility to conduct these activities for the ongoing development of omecamtiv mecarbil worldwide. Astellas has primary responsibility for the manufacturing for the ongoing development of reldesemtiv worldwide. If any partner were to terminate the development of any existing drug candidate, we would need to rely on contract manufacturers for future supply. For example, Cytokinetics and Astellas have agreed in principle to revise the terms of our collaboration to provide that Cytokinetics will obtain exclusive control over the development and commercialization of FSTAs, including reldesemtiv. If we were to assume such control, we would need to effect a transfer of the manufacturing to one or more contract manufacturers and would thereafter be solely responsible for manufacturing other than certain in-kind support and other manufacturing by Astellas. We expect to rely on contract manufacturers to supply all future drug candidates for which we conduct development, as well as other materials required to conduct our clinical trials. If any of our existing or future contract manufacturers fail to perform satisfactorily, it could delay development or regulatory approval of our drug candidates or commercialization of our drugs, producing additional losses and depriving us of potential product revenues. In addition, if a contract manufacturer fails to perform as agreed, our ability to collect damages may be contractually limited.

Our drug candidates require precise high-quality manufacturing. The failure to achieve and maintain high manufacturing standards, including failure to detect or control anticipated or unanticipated manufacturing errors or the frequent occurrence of such errors, could result in patient injury or death, discontinuance or delay of ongoing or planned clinical trials, delays or failures in product testing or delivery, cost overruns, product recalls or withdrawals and other problems that could seriously hurt our business. Contract drug manufacturers often encounter difficulties involving production yields, quality control and quality assurance and shortages of qualified personnel. These manufacturers are subject to stringent regulatory requirements, including the FDA’s current good manufacturing practices regulations and similar foreign laws and standards. Each contract manufacturer must pass a pre-approval inspection before we can obtain marketing approval for any of our drug candidates and following approval will be subject to ongoing periodic unannounced inspections by the FDA, the U.S. Drug Enforcement Agency and other regulatory agencies, to ensure strict compliance with current good manufacturing practices and other applicable government regulations and corresponding foreign laws and standards. We seek to ensure that our contract manufacturers comply fully with all applicable regulations, laws and standards. However, we do not have control over our contract manufacturers’ compliance with these regulations, laws and standards. If one of our contract manufacturers fails to pass its pre-approval inspection or maintain ongoing compliance at any time, the production of our drug candidates could be interrupted, resulting in delays or discontinuance of our clinical trials, additional costs and potentially lost revenues. In addition, failure of any third-party manufacturers or us to comply with applicable regulations, including pre- or post-approval inspections and the current good manufacturing practice requirements of the FDA or other comparable regulatory

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agencies, could result in sanctions being imposed on us. These sanctions could include fines, injunctions, civil penalties, failure of regulatory authorities to grant marketing approval of our products, delay, suspension or withdrawal of approvals, license revocation, product seizures or recalls, operational restrictions and criminal prosecutions, any of which could significantly and adversely affect our business.

In addition, our existing and future contract manufacturers may not perform as agreed or may not remain in the contract manufacturing business for the time required to successfully produce, store and distribute our drug candidates. If a natural disaster, business failure, strike or other difficulty occurs, we may be unable to replace these contract manufacturers in a timely or cost-effective manner and the production of our drug candidates would be interrupted, resulting in delays, loss of customers and additional costs.

Switching manufacturers or manufacturing sites would be difficult and time-consuming because the number of potential manufacturers is limited. In addition, before a drug from any replacement manufacturer or manufacturing site can be commercialized, the FDA and, in some cases, foreign regulatory agencies, must approve that site. These approvals would require regulatory testing and compliance inspections. A new manufacturer or manufacturing site also would have to be educated in, or develop substantially equivalent processes for, production of our drugs and drug candidates. It may be difficult or impossible to transfer certain elements of a manufacturing process to a new manufacturer or for us to find a replacement manufacturer on acceptable terms quickly, or at all, either of which would delay or prevent our ability to develop drug candidates and commercialize any resulting drugs.

We may not be able to successfully manufacture our drug candidates in sufficient quality and quantity, which would delay or prevent us from developing our drug candidates and commercializing resulting approved drugs, if any.

To date, our drug candidates have been manufactured in quantities adequate for preclinical studies and early through late-stage clinical trials. In order to conduct large scale clinical trials for a drug candidate and for commercialization of the resulting drug if that drug candidate is approved for sale, we will need to manufacture some drug candidates in larger quantities. We may not be able to successfully repeat or increase the manufacturing capacity for any of our drug candidates, whether in collaboration with third-party manufacturers or on our own, in a timely or cost-effective manner or at all. If a contract manufacturer makes improvements in the manufacturing process for our drug candidates, we may not own, or may have to share, the intellectual property rights to those improvements. Significant changes or scale-up of manufacturing may require additional validation studies, which are costly and which regulatory authorities must review and approve. In addition, quality issues may arise during those changes or scale-up activities because of the inherent properties of a drug candidate itself or of a drug candidate in combination with other components added during the manufacturing and packaging process, or during shipping and storage of the finished product or active pharmaceutical ingredients. If we are unable to successfully manufacture of any of our drug candidates in sufficient quality and quantity, the development of that drug candidate and regulatory approval or commercial launch for any resulting drugs may be delayed or there may be a shortage in supply, which could significantly harm our business. In addition, data demonstrating the stability of both drug substance and drug product, using the commercial manufacturing process and at commercial scale, are required for marketing applications. Failure to produce drug substance and drug products in a timely manner and obtain stability data could result in delay of submission of marketing applications.

The mechanisms of action of our drug candidates are unproven, and we do not know whether we will be able to develop any drug of commercial value.

We have discovered and develop drug candidates that have what we believe are novel mechanisms of action directed against cytoskeletal targets. Because no currently-approved drugs appear to operate via the same biochemical mechanisms as our compounds, we cannot be certain that our drug candidates will result in commercially viable drugs that safely and effectively treat the indications for which we intend to develop them.

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The results we have seen for our compounds in preclinical models may not translate into similar results in humans, and results of early clinical trials in humans may not be predictive of the results of larger clinical trials that may later be conducted with our drug candidates. Even if we are successful in developing and receiving regulatory approval for a drug candidate for the treatment of a particular disease, we cannot be certain that it will be accepted by prescribers or be reimbursed by insurers or that we will also be able to develop and receive regulatory approval for that or other drug candidates for the treatment of other diseases. If we or our partners are unable to successfully develop and commercialize our drug candidates, our business will be materially harmed.

Moreover, in the event any of our competitors were to develop their own drug candidates that have a similar mechanism of action to any of our drug candidates and compounds, any efficacy or safety concerns identified during the development of such similar drug candidates may have an adverse impact on the development of our own drug candidates. For example, if a competitors’ drug candidate having a similar mechanism of action as any of our own drug candidates is shown in clinical trials to give rise to serious safety concerns or have poor efficacy when administered to the target patient population, the FDA or other regulatory bodies may subject our drug candidates to increased scrutiny, leading to additional delays in development and potentially decreasing the chance of ultimate approval of our own drug candidates.

Our success depends substantially upon our ability to obtain and maintain intellectual property protection relating to our drug candidates, compounds and research technologies.

We own, co-own or hold exclusive licenses to a number of U.S. and foreign patents and patent applications directed to our drug candidates, compounds and research technologies. Our success depends on our ability to obtain patent protection both in the United States and in other countries for our drug candidates, their methods of manufacture and use, and our technologies. Our ability to protect our drug candidates, compounds and technologies from unauthorized or infringing use by third parties depends substantially on our ability to obtain and enforce our patents. If our issued patents and patent applications, if granted, do not adequately describe, enable or otherwise provide coverage of our technologies and drug candidates, we or our licensees would not be able to exclude others from developing or commercializing these drug candidates. Furthermore, the degree of future protection of our proprietary rights is uncertain because legal means may not adequately protect our rights or permit us to gain or keep our competitive advantage. If we are unable to obtain and maintain sufficient intellectual property protection for our technologies and drug candidates, or if the scope of the intellectual property protection obtained is not sufficiently broad, our competitors could develop and commercialize drug candidates similar or identical to ours, and our ability to successfully commercialize product candidates that we may pursue may be impaired.

Obtaining and enforcing biopharmaceutical patents is costly, time consuming and complex, and we may not be able to file and prosecute all necessary or desirable patent applications, or maintain, enforce and license any patents that may issue from such patent applications, at a reasonable cost or in a timely manner. It is also possible that we will fail to identify patentable aspects of our research and development output before it is too late to obtain patent protection. We may not have the right to control the preparation, filing and prosecution of patent applications, or to maintain the rights to patents licensed to third parties. Therefore, these patents and applications may not be prosecuted and enforced in a manner consistent with the best interests of our business.

Due to evolving legal standards relating to the patentability, validity and enforceability of patents covering pharmaceutical inventions and the claim scope of these patents, our ability to enforce our existing patents and to obtain and enforce patents that may issue from any pending or future patent applications is uncertain and involves complex legal, scientific and factual questions. The standards which the U.S. Patent and Trademark Office and its foreign counterparts use to grant patents are not always applied predictably or uniformly and are subject to change. To date, no consistent policy has emerged regarding the breadth of claims allowed in biotechnology and pharmaceutical patents. Thus, we cannot be sure that any patents will issue from any pending or future patent applications owned by, co-owned by or licensed to us. Even if patents do issue, we cannot be sure that the claims of these patents will be held valid or enforceable by a court of law, will provide us with any

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significant protection against competitive products, or will afford us a commercial advantage over competitive products. In particular:

We may not be able to protect our intellectual property rights throughout the world. Patent protection is afforded on a country-by-country basis. Filing, prosecuting and defending patents on our product candidates in all countries throughout the world would be prohibitively expensive, and our intellectual property rights in some countries outside the United States can be less extensive than those in the United States. Many companies have encountered significant difficulties in protecting and defending intellectual property rights in foreign jurisdictions. Some of our development efforts are performed in countries outside of the United States through third-party contractors. We may not be able to effectively monitor and assess intellectual property developed by these contractors. We therefore may not be able to effectively protect this intellectual property and could lose potentially valuable intellectual property rights. In addition, the legal protection afforded to inventors and owners of intellectual property in countries outside of the United States may not be as protective of intellectual property rights as in the United States. Therefore, we may be unable to acquire and protect intellectual property developed by these contractors to the same extent as if these development activities were being conducted in the United States. If we encounter difficulties in protecting our intellectual property rights in foreign jurisdictions, our business prospects could be substantially harmed.

Patent terms may be inadequate to protect our competitive position on our technologies and drug candidates for an adequate amount of time. Patents have a limited lifespan. In the United States, if all maintenance fees are timely paid, the natural expiration of a patent is generally 20 years from its earliest U.S. non-provisional filing date. Various extensions may be available, but the life of a patent, and the protection it affords, is limited. Even if patents covering our technologies and drug candidates are obtained, once the patent life has expired, we may be open to competition from competitive products, including generics or biosimilars. Given the amount of time required for the development, testing and regulatory review of new drug candidates, patents protecting such candidates might expire before or shortly after such candidates are commercialized. As a result, our owned, co-owned and licensed patent portfolio may not provide us with sufficient rights to exclude others from commercializing products similar or identical to ours or our partners.

Obtaining and maintaining our patent protection depends on compliance with various procedural, document submission, fee payment and other requirements imposed by governmental patent agencies, and our patent protection could be reduced or eliminated for non-compliance with these requirements. Periodic maintenance

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fees, renewal fees, annuity fees and various other governmental fees on patents and/or applications will be due to be paid to the United States Patent and Trademark Office and various governmental patent agencies outside of the United States in several stages over the lifetime of the patents and/or applications. Non-compliance could result in abandonment or lapse of the patent or patent application, resulting in partial or complete loss of patent rights in the relevant jurisdiction. In such an event, our competitors might be able to enter the market and this circumstance would have a material adverse effect on our business.

We may be subject to claims challenging the inventorship or ownership of our patents and other intellectual property. We rely on intellectual property assignment agreements with our corporate partners, employees, consultants, scientific advisors and other collaborators to grant us ownership of new intellectual property that is developed. These agreements may not result in the effective assignment to us of that intellectual property. As a result, our ownership of key intellectual property could be compromised.

We or our licensors may be subject to claims that former employees, collaborators, consultants or other third parties have an interest in our owned, co-owned or in-licensed patents, trade secrets, or other intellectual property as an inventor or co-inventor. For example, we or our licensors may have inventorship disputes arise from conflicting obligations of employees, collaborators, consultants or others who are involved in developing our product candidates. Litigation may be necessary to defend against these and other claims challenging inventorship or our or our licensors’ ownership of our owned, co-owned or in-licensed patents, trade secrets or other intellectual property. If we or our licensors fail in defending any such claims, in addition to paying monetary damages, we may lose valuable intellectual property rights, such as exclusive ownership of, or right to use, intellectual property that is important to our product candidates. Even if we are successful in defending against such claims, litigation could result in substantial costs and be a distraction to management and other employees. Any of the foregoing could have a material adverse effect on our business, financial condition, results of operations and prospects.

We are a party to license agreements and may need to obtain additional licenses from others to advance our research and development activities or allow the commercialization of our drug candidates and future drug candidates we may identify and pursue. If we fail to comply with our obligations in the agreements under which we license intellectual property rights from third parties or these agreements are terminated or we otherwise experience disruptions to our business relationships with our licensors, we could lose intellectual property rights that are important to our business. Our licensors might conclude that we have materially breached our obligations under such license agreements and might therefore terminate, or seek to terminate, the license agreements, thereby removing or limiting our ability to develop and commercialize products and technology covered by these license agreements. If our license agreements are terminated, we may be required to cease our development and commercialization of our product candidates. Any of the foregoing could have a material adverse effect on our competitive position, business, financial conditions, results of operations and prospects. Moreover, disputes may arise regarding intellectual property subject to a licensing agreement. The resolution of any contract interpretation disagreement that may arise could narrow what we believe to be the scope of our rights to the relevant intellectual property or technology, or increase what we believe to be our financial or other obligations under the agreement, either of which could have a material adverse effect on our business, financial condition, results of operations and prospects. Moreover, if disputes over intellectual property that we have licensed prevent or impair our ability to maintain our current licensing arrangements on commercially acceptable terms, we may be unable to successfully develop and commercialize the affected product candidates. Any of the foregoing could have a material adverse effect on our competitive position, business, financial conditions, results of operations and prospects.

Changes in either the patent laws or their interpretation in the United States or other countries may diminish the value of our intellectual property or our ability to obtain patents. For example, the America Invents Act of 2011 may affect the scope, strength and enforceability of our patent rights in the United States or the nature of proceedings which may be brought by us related to our patent rights in the United States.

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If one or more products resulting from our drug candidates is approved for sale by the FDA and we do not have adequate intellectual property protection for those products, competitors could duplicate them for approval and sale in the United States without repeating the extensive testing required of us or our partners to obtain FDA approval. Regardless of any patent protection, under current law, an application for a generic version of a new chemical entity cannot be approved until at least five years after the FDA has approved the original product. When that period expires, or if that period is altered, the FDA could approve a generic version of our product regardless of our patent protection. An applicant for a generic version of our product may only be required to conduct a relatively inexpensive study to show that its product is bioequivalent to our product, and may not have to repeat the lengthy and expensive clinical trials that we or our partners conducted to demonstrate that the product is safe and effective. In the absence of adequate patent protection for our products in other countries, competitors may similarly be able to obtain regulatory approval in those countries of generic versions of our products.

If we are unable to protect the confidentiality of our trade secrets, the value of our technology could be materially adversely affected and our business would be harmed.

We also rely on trade secrets to protect our technology, particularly where we believe patent protection is not appropriate or obtainable. However, trade secrets are often difficult to protect, especially outside of the United States. While we endeavor to use reasonable efforts to protect our trade secrets, our or our partners’ employees, consultants, contractors or scientific and other advisors may unintentionally or willfully disclose our information to competitors. In addition, confidentiality agreements, if any, executed by those individuals may not be enforceable or provide meaningful protection for our trade secrets or other proprietary information in the event of unauthorized use or disclosure. We cannot be certain that such agreements have been entered into with all relevant parties, and we cannot be certain that our trade secrets and other confidential proprietary information will not be disclosed or that competitors will not otherwise gain access to our trade secrets or independently develop substantially equivalent information and techniques. Pursuing a claim that a third party had illegally obtained and was using our trade secrets would be expensive and time-consuming, and the outcome would be unpredictable. Even if we are able to maintain our trade secrets as confidential, if our competitors lawfully obtain or independently develop information equivalent or similar to our trade secrets, our business could be harmed.

If we are not able to defend the patent or trade secret protection position of our technologies and drug candidates, then we will not be able to exclude competitors from developing or marketing competing drugs, and we may not generate enough revenue from product sales to justify the cost of development of our drugs or to achieve or maintain profitability.

If we are sued for infringing third-party intellectual property rights, it will be costly and time-consuming, and an unfavorable outcome could have a significant adverse effect on our business.

Our ability to commercialize drugs depends on our ability to use, manufacture and sell those drugs without infringing the patents or other proprietary rights of third parties. Numerous U.S. and foreign issued patents and pending patent applications owned by third parties exist in the therapeutic areas in which we are developing drug candidates and seeking new potential drug candidates. In addition, because patent applications can take several years to issue, there may be currently pending applications, unknown to us, which could later result in issued patents that our activities with our drug candidates could infringe. There may also be existing patents, unknown to us, that our activities with our drug candidates could infringe.

Other future products of ours may be impacted by patents of companies engaged in competitive programs with significantly greater resources. Further development of these products could be impacted by these patents and result in significant legal fees.

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If a third party claims that our actions infringe its patents or other proprietary rights, we could face a number of issues that could seriously harm our competitive position, including, but not limited to:

If any of these events occur, it could significantly harm our business and negatively affect our stock price.

We may undertake infringement or other legal proceedings against third parties, causing us to spend substantial resources on litigation and exposing our own intellectual property portfolio to challenge.

Third parties may infringe our patents. To prevent infringement or unauthorized use, we may need to file infringement suits, which are expensive and time-consuming. In an infringement proceeding, a court may decide that one or more of our patents is invalid, unenforceable, or both. In such case third parties may be able to use our technology without paying licensing fees or royalties. Even if the validity of our patents is upheld, a court may refuse to stop the other party from using the technology at issue on the ground that the other party’s activities are not covered by our patents. Policing unauthorized use of our intellectual property is difficult, and we may not be able to prevent misappropriation of our proprietary rights, particularly in countries where the laws may not protect such rights as fully as in the United States. In addition, third parties may affirmatively challenge our rights to, or the scope or validity of, our patent rights.

The uncertainties associated with litigation could have a material adverse effect on our ability to raise the funds necessary to conduct clinical trials, continue our research programs, license necessary technology from third parties, or enter into development partnerships that would help us bring our drug candidates or other product candidates that we may identify to market. Furthermore, because of the substantial amount of discovery required in connection with intellectual property litigation, there is a risk that some of our confidential information could be compromised by disclosure during this type of litigation. There could also be public announcements of the results of hearings, motions, or other interim proceedings or developments. If securities analysts or investors perceive these results to be negative, it could have a material adverse effect on the price of our common stock.

We may become involved in disputes with our strategic partners over intellectual property ownership, and publications by our research collaborators and clinical investigators could impair our ability to obtain patent protection or protect our proprietary information, either of which would have a significant impact on our business.

Inventions discovered under our current or future strategic alliance agreements may become jointly owned by our strategic partners and us in some cases, and the exclusive property of one of us in other cases. Under some circumstances, it may be difficult to determine who owns a particular invention or whether it is jointly owned, and disputes could arise regarding ownership or use of those inventions. These disputes could be costly and time-consuming, and an unfavorable outcome could have a significant adverse effect on our business if we were not able to protect or license rights to these inventions. In addition, our research collaborators and clinical investigators generally have contractual rights to publish data arising from their work. Publications by our research collaborators and clinical investigators relating to our research and development programs, either with or without our consent, could benefit our current or potential competitors and may impair our ability to obtain patent protection or protect our proprietary information, which could significantly harm our business.

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We may be subject to claims that our employees, consultants or independent contractors have wrongfully used or disclosed confidential information of third parties or that we or our employees have wrongfully used or disclosed trade secrets of their former employers.

Many of our employees were previously employed at universities or other biotechnology or pharmaceutical companies, including our competitors or potential competitors. Although no legal proceedings against us are currently pending, we may be subject to claims that these employees or we have inadvertently or otherwise used or disclosed trade secrets or other proprietary information of their former employers. Litigation may be necessary to defend against these claims. If we fail in defending these claims, in addition to paying monetary damages, we may lose valuable intellectual property rights or personnel. A loss of key research personnel or their work product could hamper or prevent our ability to develop and commercialize certain potential drugs, which could significantly harm our business. Even if we are successful in defending against these claims, litigation could result in substantial costs and distract management.

Our competitors may develop drugs that are less expensive, safer or more effective than ours, which may diminish or eliminate the commercial success of any drugs that we may commercialize.

We compete with companies that have developed drugs or are developing drug candidates for cardiovascular diseases, diseases and conditions associated with muscle weakness or wasting and other diseases for which our drug candidates may be useful treatments. For example, if reldesemtiv is approved for marketing by the FDA or other regulatory authorities for the treatment of ALS, it will then compete with RADICAVA^tm (edaravone), the first FDA approved drug for the treatment of ALS since riluzole in 1995, and may then compete with other potential new therapies for ALS that are currently being developed by companies including, but not limited to, Orphazyme, NeuralStem, MediciNova, Ionis Pharmaceuticals, Inc. (in collaboration with Biogen Inc.), AB Sciences, Orion, Pharmaceuticals, Mitsubishi Tanabe Pharma Corporation, Treeway, Genentech, Inc., and BrainStorm Cell Therapeutics. Also, if reldesemtiv is approved by the FDA or other regulatory authorities for the treatment of SMA, it will then compete with SPINRAZA^® (nusinersen) and Zolgensma^® (onasemnogene abeparvovec-xioi) and may then compete with other potential new therapies being developed by companies including, but not limited to, Roche (in collaboration with PTC Therapeutics). If reldesemtiv is approved by the FDA or other regulatory authorities for the treatment of non-neuromuscular indications associated with muscle weakness, it may then compete with other potential new therapies being developed by companies including, but not limited to, Regeneron Pharmaceuticals, Inc. (in collaboration with Sanofi), Eli Lilly and Company, Stealth Biotherapeutics, and Novartis (in collaboration with MorphoSys AG).

If omecamtiv mecarbil is approved for marketing by the FDA or other regulatory authorities for the treatment of heart failure, it would compete against other drugs used for the treatment of acute and chronic heart failure. These include generic drugs, such as milrinone, dobutamine or digoxin and branded drugs such as Natrecor^® (nesiritide), Corlanor^® (ivabradine), and Entresto^® (sacubitril/valsartan). Omecamtiv mecarbil could also potentially compete against other novel drug candidates and therapies in development, such as those being developed by, but not limited to, Novartis, Bayer, Stealth Biotherapeutics, and MyoKardia. Omecamtiv mecarbil may also compete with currently approved products, such as in the SGLT2 class, that may expand their labels to include treatment of patients with heart failure, including Forxiga^®, Invokana^®, and Jardiance^®. In addition, there are a number of medical devices both marketed and in development for the potential treatment of heart failure.

Our competitors may:

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We will compete for market share against large pharmaceutical and biotechnology companies and smaller companies that are collaborating with larger pharmaceutical companies, new companies, academic institutions, government agencies and other public and private research organizations. Many of these competitors, either alone or together with their partners, may develop new drug candidates that will compete with ours. Many of these competitors have larger research and development programs or substantially greater financial resources than we do. Our competitors may also have significantly greater experience in:

If our competitors market drugs that are less expensive, safer or more efficacious than our potential drugs, or that reach the market sooner than our potential drugs, we may not achieve commercial success. In addition, the life sciences industry is characterized by rapid technological change. If we fail to stay at the forefront of technological change, we may be unable to compete effectively. Our competitors may render our technologies obsolete by improving existing technological approaches or developing new or different approaches, potentially eliminating the advantages in our drug discovery process that we believe we derive from our research approach and proprietary technologies.

We have been granted orphan designation by the FDA and EMA for reldesemtiv for the potential treatment of SMA; however, there can be no guarantee that we will receive orphan approval for reldesemtiv, nor that we will be able to prevent third parties from developing and commercializing products that are competitive to reldesemtiv.

We have been granted orphan drug designation in the U.S. by the FDA for reldesemtiv for the potential treatment of SMA. In the U.S., upon approval from the FDA of an NDA, products granted orphan drug designation are generally provided with seven years of marketing exclusivity in the U.S., meaning the FDA will generally not approve applications for other product candidates that contain the same active ingredient for the same orphan indication. Even if we are the first to obtain approval of an orphan product and are granted such exclusivity in the U.S., there are limited circumstances under which a later competitor product may be approved for the same indication during the seven-year period of marketing exclusivity, such as if the later product is shown to be clinically superior to our product or due to an inability to assure a sufficient quantity of the orphan drug.

EMA has granted orphan medicinal product designation to reldesemtiv for the potential treatment of SMA. Orphan medicinal product status in the Europe Union can provide up to 10 years of marketing exclusivity, meaning that another application for marketing authorization of a later similar medicinal product for the same

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therapeutic indication will generally not be approved in the European Union. Although we may have drug candidates that may obtain orphan drug exclusivity in Europe, the orphan approval and associated exclusivity period may be modified for several reasons, including a significant change to the orphan medicinal product designations or approval criteria after-market authorization of the orphan product (e.g., product profitability exceeds the criteria for orphan drug designation), problems with the production or supply of the orphan drug or a competitor drug, although similar, is safer, more effective or otherwise clinically superior than the initial orphan drug.

We are not guaranteed to maintain orphan status for reldesemtiv or to receive orphan status for reldesemtiv for any other indication or for any of our other drug candidates for any indication. If our drug candidates that are granted orphan status were to lose their status as orphan drugs or the marketing exclusivity provided for them in the U.S. or the European Union, our business and results of operations could be materially adversely affected. While orphan status for any of our products, if granted or maintained, would provide market exclusivity in the U.S. and the European Union for the time periods specified above, we would not be able to exclude other companies from manufacturing and/or selling products using the same active ingredient for the same indication beyond the exclusivity period applicable to our product on the basis of orphan drug status. Moreover, we cannot guarantee that another company will not receive approval before we do of an orphan drug application in the U.S. or the European Union for a product candidate that has the same active ingredient or is a similar medicinal product for the same indication as any of our drug candidates for which we plan to file for orphan designation and status. If that were to happen, our orphan drug applications for our drug candidate for that indication may not be approved until the competing company’s period of exclusivity has expired in the U.S. or the European Union, as applicable. Further, application of the orphan drug regulations in the U.S. and Europe is uncertain, and we cannot predict how the respective regulatory bodies will interpret and apply the regulations to our or our competitors’ products.

Our failure to attract and retain skilled personnel could impair our drug development, commercialization and financial reporting activities.

Our business depends on the performance of our senior management and key scientific and technical personnel. The loss of the services of any member of our senior management or key scientific, technical or financial reporting staff may significantly delay or prevent the achievement of drug development and other business objectives by diverting management’s attention to transition matters and identifying suitable replacements. For example, our management concluded that our internal controls over financial reporting were not effective as of December 31, 2018 because an unremediated material weakness existed in our internal control over financial reporting related to employee turnover resulting in a temporary lack of resources in financial reporting roles with the appropriate skills to perform effective review during our financial statement close process. We also rely on consultants and advisors to assist us in formulating our research and development strategy. All of our consultants and advisors are either self-employed or employed by other organizations, and they may have conflicts of interest or other commitments, such as consulting or advisory contracts with other organizations, that may affect their ability to contribute to us. In addition, if and as our business grows, we will need to recruit additional executive management and scientific, technical and financial reporting personnel. There is intense competition for skilled executives and employees with relevant scientific and technical expertise, and this competition is likely to continue. Our inability to attract and retain sufficient scientific, technical and managerial personnel could limit or delay our product development activities, which would adversely affect the development of our drug candidates and commercialization of our potential drugs and growth of our business.

Any future workforce and expense reductions may have an adverse impact on our internal programs and our ability to hire and retain skilled personnel.

Our future success will depend in large part upon our ability to attract and retain highly skilled personnel. In light of our continued need for funding and cost control, we may be required to implement future workforce and expense reductions, which could further limit our research and development activities. We may have difficulty

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retaining and attracting such personnel as a result of a perceived risk of future workforce reductions. In addition, the implementation of any workforce or expense reduction programs may divert the efforts of our management team and other key employees, which could adversely affect our business.

We may expand our development and clinical research capabilities and, as a result, we may encounter difficulties in managing our growth, which could disrupt our operations.

We may have growth in our expenditures, the number of our employees and the scope of our operations, in particular with respect to those drug candidates that we elect to develop or commercialize independently or together with a partner. To manage our anticipated future growth, we must continue to implement and improve our managerial, operational and financial systems, expand our facilities and continue to recruit and train additional qualified personnel. Due to our limited resources, we may not be able to effectively manage the expansion of our operations or recruit and train additional qualified personnel. The physical expansion of our operations may lead to significant costs and may divert our management and business development resources. Any inability to manage growth could delay the execution of our business plans or disrupt our operations.

We currently have no sales or marketing capabilities and, if we are unable to enter into or maintain strategic alliances with marketing partners or to develop our own sales and marketing capabilities, we may not be successful in commercializing our potential drugs.

We currently have no sales, marketing or distribution capabilities. We plan to commercialize drugs that can be effectively marketed and sold in concentrated markets that do not require a large sales force to be competitive. To achieve this goal, we will need to establish our own specialized sales force and marketing organization with technical expertise and supporting distribution capabilities. Developing such an organization is expensive and time-consuming and could delay a product launch. In addition, we may not be able to develop this capacity efficiently, cost-effectively or at all, which could make us unable to commercialize our drugs. If we determine not to market our drugs on our own, we will depend on strategic alliances with third parties, such as Amgen and Astellas, which have established distribution systems and direct sales forces to commercialize them. If we are unable to enter into such arrangements on acceptable terms, we may not be able to successfully commercialize these drugs. To the extent that we are not successful in commercializing any drugs ourselves or through a strategic alliance, our product revenues and business will suffer and our stock price would decrease.

Our internal computer systems, or those of our CROs, CMOs, supply chain partners, collaboration partners or other contractors or consultants, may fail or suffer security breaches, which could result in a material disruption of our drug development programs.

Despite the implementation of security measures, our internal computer systems and those of our third-party CROs, CMOs, supply chain partners, collaboration partners and other contractors and consultants are vulnerable to damage from computer viruses, unauthorized access, natural disasters, terrorism, war and telecommunication and electrical failures. If such an event were to occur and cause interruptions in our operations, it could result in a material disruption of our drug development programs. For example, the loss of clinical study data from completed or ongoing clinical studies for any of our drug candidates could result in delays in our regulatory approval efforts and significantly increase our costs to recover or reproduce the data. To the extent that any disruption or security breach were to result in a loss of or damage to our data or applications, or inappropriate disclosure of confidential or proprietary information, we could incur liability, our operations could be compromised and the further development of our product candidates could be delayed.

Significant disruptions of information technology systems or breaches of data security could adversely affect our business.

Our business is increasingly dependent on complex and interdependent information technology systems, including internet-based systems, databases and programs, to support our business processes as well as internal

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and external communications. As use of information technology systems has increased, deliberate attacks and attempts to gain unauthorized access to computer systems and networks have increased in frequency and sophistication. Our information technology, systems and networks are potentially vulnerable to breakdown, malicious intrusion and computer viruses which may result in the impairment of production and key business processes or loss of data or information. We are also potentially vulnerable to data security breaches—whether by employees or others—which may expose sensitive data to unauthorized persons. We have in the past and may in the future be subject to security breaches. For example, in February 2018, we discovered that our e-mail server suffered unauthorized intrusions in which proprietary business information was accessed. Although we do not believe that we have experienced any material losses related to security breaches, including in two recent email “phishing” incidents, there can be no assurance that we will not suffer such losses in the future. Breaches and other inappropriate access can be difficult to detect and any delay in identifying them could increase their harm. While we have implemented security measures to protect our data security and information technology systems, such measures may not prevent such events. Any such breaches of security and inappropriate access could disrupt our operations, harm our reputation or otherwise have a material adverse effect on our business, financial condition and results of operations.

Our reported financial results may be adversely affected by changes in accounting principles generally accepted in the U.S.

We prepare our financial statements in conformity with accounting principles generally accepted in the U.S. These accounting principles are subject to interpretation by the Financial Accounting Standards Board and the SEC. A change in these policies or interpretations could have a significant effect on our reported financial results, may retroactively affect previously reported results, could cause unexpected financial reporting fluctuations, and may require us to make costly changes to our operational processes and accounting systems.

We are a smaller reporting company, and any decision on our part to comply only with certain reduced reporting and disclosure requirements applicable to smaller reporting companies could make our common stock less attractive to investors.

We are a “smaller reporting company,” as defined under the Exchange Act, in accordance with the amendments to such definition that became effective on September 10, 2018. For as long as we continue to be a smaller reporting company, we may choose to take advantage of exemptions from various reporting requirements applicable to other public companies that are not smaller reporting companies, including, but not limited to, reduced disclosure obligations regarding executive compensation in our periodic reports and proxy statements. In addition, as a smaller reporting company, we are only required to include two years of audited financial statements in our annual reports. Investors could find our common stock less attractive if we choose to rely on these scaled disclosure requirements. If some investors find our common stock less attractive as a result of any choices to reduce future disclosure, there may be a less active trading market for our common stock and our stock price may be more volatile.

We will remain a “smaller reporting company” until (i) the market value of our common shares held by non-affiliates exceeds $250 million as of June 30 of any year; or (ii) either (a) our annual revenues exceed $100 million or (b) the market value of our common shares held by non-affiliates exceeds $700 million, as of June 30 of any year.

Our revenue to date has been primarily derived from our research and license agreements, which can result in significant fluctuation in our revenue from period to period, and our past revenue is therefore not necessarily indicative of our future revenue.

Our revenue is primarily derived from our research and license agreements, from which we receive upfront fees, contract research payments, milestone and other contingent payments based on clinical progress, regulatory progress or net sales achievements and royalties. Significant variations in the timing of receipt of cash payments

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and our recognition of revenue can result from significant payments based on the execution of new research and license agreements, the timing of clinical outcomes, regulatory approval, commercial launch or the achievement of certain annual sales thresholds. The amount of our revenue derived from research and license agreements in any given period will depend on a number of unpredictable factors, including our ability to find and maintain suitable collaboration partners, the timing of the negotiation and conclusion of collaboration agreements with such partners, whether and when we or our collaboration partners achieve clinical, regulatory and sales milestones, the timing of regulatory approvals in one or more major markets, reimbursement levels by private and government payers, and the market introduction of new drugs or generic versions of the approved drug, as well as other factors. Our past revenue generated from these agreements is not necessarily indicative of our future revenue. If any of our existing or future collaboration partners fails to develop, obtain regulatory approval for, manufacture or ultimately commercialize any product candidate under our collaboration agreement, our business, financial condition, and results of operations could be materially and adversely affected.

The Term Loan bears interest at variable interest rates based on LIBOR. Changes in the method of determining LIBOR, or the replacement of LIBOR with an alternative reference rate, may adversely affect interest rates on our current or future indebtedness and may otherwise adversely affect our financial condition and results of operations.

In July 2017, the Financial Conduct Authority, the authority that regulates LIBOR, announced that it intended to stop compelling banks to submit rates for the calculation of LIBOR after 2021. The Alternative Reference Rates Committee, or ARRC, in the U.S. has proposed that the Secured Overnight Financing Rate, SOFR, is the rate that represents best practice as the alternative to the U.S. dollar LIBOR for use in derivatives and other financial contracts that are currently indexed to LIBOR. ARRC has proposed a paced market transition plan to SOFR from U.S. dollar LIBOR and organizations are currently working on industry-wide and company-specific transition plans as relating to derivatives and cash markets exposed to U.S. dollar LIBOR. We have certain financial contracts, including the loan agreement governing the Term Loan, that are indexed to U.S. dollar LIBOR. Changes in the method of determining LIBOR, or the replacement of LIBOR with an alternative reference rate, may adversely affect interest rates on our current or future indebtedness. Any transition process may involve, among other things, increased volatility or illiquidity in markets for instruments that rely on LIBOR, reductions in the value of certain instruments or the effectiveness of related transactions such as hedges, increased borrowing costs, uncertainty under applicable documentation, or difficult and costly consent processes. We are monitoring this activity and evaluating the related risks, and any such effects of the transition away from LIBOR may result in increased expenses, may impair our ability to refinance our indebtedness or hedge our exposure to floating rate instruments, or may result in difficulties, complications or delays in connection with future financing efforts, any of which could adversely affect our financial condition and results of operations.

Risks Related to Our Industry

The regulatory approval process is expensive, time-consuming and uncertain and may prevent our partners or us from obtaining approvals to commercialize some or all of our drug candidates.

The research, testing, manufacturing, selling and marketing of drugs are subject to extensive regulation by the FDA and other regulatory authorities in the United States and other countries, and regulations differ from country to country. Neither we nor our partners are permitted to market our potential drugs in the United States until we receive approval of a new drug application, or NDA, from the FDA. Neither we nor our partners have received NDA or other marketing approval for any of our drug candidates.

Obtaining NDA approval is a lengthy, expensive and uncertain process. In addition, failure to comply with FDA and other applicable foreign and U.S. regulatory requirements may subject us to administrative or judicially imposed sanctions. These include warning letters, civil and criminal penalties, injunctions, product seizure or detention, product recalls, total or partial suspension of production, and refusal to approve pending NDAs or supplements to approved NDAs.

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Regulatory approval of an NDA or NDA supplement is never guaranteed, and the approval process typically takes several years and is extremely expensive. The FDA and foreign regulatory agencies also have substantial discretion in the drug approval process, and the guidance and advice issued by such agencies is subject to change at any time. Despite the time and efforts exerted, failure can occur at any stage, and we may encounter problems that cause us to abandon clinical trials or to repeat or perform additional preclinical testing and clinical trials. The number and focus of preclinical studies and clinical trials that will be required for approval by the FDA and foreign regulatory agencies varies depending on the drug candidate, the disease or condition that the drug candidate is designed to address, and the regulations applicable to any particular drug candidate. In addition, the FDA may require that a proposed Risk Evaluation and Mitigation Strategy, or REMS, be submitted as part of an NDA if the FDA determines that it is necessary to ensure that the benefits of the drug outweigh its risks. The FDA and foreign regulatory agencies can delay, limit or deny approval of a drug candidate for many reasons, including, but not limited to:

Even if we receive regulatory approval to manufacture and sell a drug in a particular regulatory jurisdiction, other jurisdictions’ regulatory authorities may not approve that drug for manufacture and sale. If we or our partners fail to receive and maintain regulatory approval for the sale of any drugs resulting from our drug candidates, it would significantly harm our business and negatively affect our stock price.

If we or our partners receive regulatory approval for our drug candidates, we or they will be subject to ongoing obligations to and continued regulatory review by the FDA and foreign regulatory agencies, and may be subject to additional post-marketing obligations, all of which may result in significant expense and limit commercialization of our potential drugs.

Any regulatory approvals that we or our partners receive for our drug candidates may be subject to limitations on the indicated uses for which the drug may be marketed or require potentially costly post-marketing follow-up studies or compliance with a REMS. In addition, if the FDA or foreign regulatory agencies approves any of our drug candidates, the labeling, packaging, adverse event reporting, storage, advertising, promotion and record-keeping for the drug will be subject to extensive regulatory requirements. The subsequent discovery of previously unknown problems with the drug, including adverse events of unanticipated severity or frequency, or the discovery that adverse events or toxicities observed in preclinical research or clinical trials that were believed to be minor constitute much more serious problems, may result in restrictions on the marketing of the drug or withdrawal of the drug from the market.

The FDA and foreign regulatory agencies may change their policies and additional government regulations may be enacted that could prevent or delay regulatory approval of our drug candidates. We cannot predict the likelihood, nature or extent of adverse government regulation that may arise from future legislation or administrative action, either in the United States or abroad. If we are not able to maintain regulatory compliance, we might not be permitted to market our drugs and our business would suffer.

If physicians and patients do not accept our drugs, we may be unable to generate significant revenue, if any.

Even if our drug candidates obtain regulatory approval, the resulting drugs, if any, may not gain market acceptance among physicians, healthcare payors, patients and the medical community. Even if the clinical safety

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and efficacy of drugs developed from our drug candidates are established for purposes of approval, physicians may elect not to recommend these drugs for a variety of reasons including, but not limited to:

If our drugs fail to achieve market acceptance, we may not be able to generate significant revenue and our business would suffer.

Recently enacted and future legislation, including potentially unfavorable pricing regulations or other healthcare reform initiatives, may increase the difficulty and cost for us to obtain regulatory approval of and commercialize our product candidates and affect the prices we may obtain.

The regulations that govern, among other things, regulatory approvals, coverage, pricing and reimbursement for new drug products vary widely from country to country. In the United States and some foreign jurisdictions, there have been a number of legislative and regulatory changes and proposed changes regarding the healthcare system that could prevent or delay regulatory approval of our product candidates, restrict or regulate post-approval activities and affect our ability to successfully sell any product candidates for which we obtain regulatory approval. In particular, in March 2010, the Patient Protection and Affordable Care Act, as amended by the Health Care and Education Reconciliation Act, or collectively, the ACA, was enacted, which substantially changes the way health care is financed by both governmental and private insurers, and significantly impacts the U.S. pharmaceutical industry. The ACA and its implementing regulations, among other things, addressed a new methodology by which rebates owed by manufacturers under the Medicaid Drug Rebate Program are calculated for certain drugs and biologics, including our product candidates that are inhaled, infused, instilled, implanted or injected, increased the minimum Medicaid rebates owed by manufacturers under the Medicaid Drug Rebate Program, extended the Medicaid Drug Rebate Program to utilization of prescriptions of individuals enrolled in Medicaid managed care organizations, subjected manufacturers to new annual fees and taxes for certain branded prescription drugs, provided incentives to programs that increase the federal government’s comparative effectiveness research and established a new Medicare Part D coverage gap discount program.

Other legislative changes have been proposed and adopted in the United States since the ACA was enacted. In August 2011, the Budget Control Act of 2011, among other things, created measures for spending reductions by the U.S. Congress. A Joint Select Committee on Deficit Reduction, tasked with recommending a targeted deficit reduction of at least $1.2 trillion for the years 2013 through 2021, was unable to reach required goals, thereby triggering the legislation’s automatic reduction to several government programs. This includes aggregate reductions of Medicare payments to providers of 2% per fiscal year, which went into effect in April 2013, and, due to subsequent legislative amendments, will remain in effect through 2029 unless additional Congressional action is taken. In January 2013, the American Taxpayer Relief Act of 2012 was enacted which, among other things, further reduced Medicare payments to several providers, including hospitals and outpatient clinics, and increased the statute of limitations period for the government to recover overpayments to providers from three to five years.

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Since its enactment, there have been judicial and Congressional challenges to numerous elements of the ACA, as well as efforts by both the executive and legislative branches of the federal government to repeal or replace certain aspects of the ACA. For example, the President signed Executive Orders designed to delay the implementation of certain provisions of the ACA or otherwise circumvent some of the requirements for health insurance mandated by the ACA. In addition, the U.S. Congress has considered legislation that would repeal or repeal and replace all or part of the ACA. While the U.S. Congress has not passed comprehensive repeal legislation, it has enacted laws that modify certain provisions of the ACA, such as removing penalties, starting January 1, 2019, for not complying with the ACA’s individual mandate to carry health insurance, delaying the implementation of certain mandated fees, and increasing the point-of-sale discount that is owed by pharmaceutical manufacturers who participate in Medicare Part D. In December 2018, a Texas U.S. District Court Judge ruled that the ACA is unconstitutional in its entirety because the “individual mandate” was repealed by Congress as part of the Tax Cuts and Jobs Act of 2017, or the Tax Act. The Texas U.S. District Court Judge, as well as the presidential administration and the CMS, have stated that the ruling will have no immediate effect pending appeal of the decision, but it is unclear how this decision, subsequent appeals, and other efforts to repeal and replace the ACA will impact the ACA and our business. The U.S. Congress may consider and adopt other legislation to repeal and replace all or certain elements of the ACA. Any other executive, legislative or judicial action to “repeal and replace” all or part of the ACA may have the effect of limiting the amounts that government agencies will pay for healthcare products and services, which could result in reduced demand for our products or additional pricing pressure, or may lead to significant deregulation, which could make the introduction of competing products and technologies much easier. Policy changes, including potential modification or repeal of all or parts of the ACA or the implementation of new health care legislation, could result in significant changes to the health care system which may adversely affect our business in unpredictable ways.

There have been, and likely will continue to be, legislative and regulatory proposals at the foreign, federal and state levels directed at broadening the availability of healthcare and containing or lowering the cost of healthcare. We cannot predict the initiatives that may be adopted in the future. The continuing efforts of governments, insurance companies, managed care organizations and other payors of healthcare services to contain or reduce costs of healthcare, including by imposing price controls, may adversely affect the demand for our product candidates for which we obtain regulatory approval and our ability to set a price that we believe is fair for our products. Any reduction in reimbursement from Medicare or other government programs may result in a similar reduction in payments from private payors.

Legislative and regulatory proposals have been made to expand post-approval requirements and restrict sales and promotional activities for pharmaceutical products. We cannot be sure whether additional legislative changes will be enacted, or whether the FDA or foreign regulations, guidance or interpretations will be changed, or what the impact of these changes on the regulatory approvals of our product candidates, if any, may be. In the United States, the European Union and other potentially significant markets for our product candidates, government authorities and third-party payors are increasingly attempting to limit or regulate the price of medical products and services, particularly for new and innovative products and therapies, which has resulted in lower average selling prices. For example, in the United States, there have been several recent Congressional inquiries and proposed and enacted federal and state legislation designed to, among other things, bring more transparency to drug pricing, review the relationship between pricing and manufacturer patient programs, and reform government program reimbursement methodologies for drugs. Additionally, in May 2018, the U.S. presidential administration laid out a “Blueprint” to lower drug prices and reduce out of pocket costs of drugs that contains additional proposals to increase manufacturer competition, increase the negotiating power of certain federal healthcare programs, incentivize manufacturers to lower the list price of their products and reduce the out of pocket costs of drug products paid by consumers. The U.S. Department of Health and Human Services, or HHS, has started the process of soliciting feedback on some of these measures and, at the same time, is immediately implementing others under its existing authority. In January 2019, the HHS Office of Inspector General proposed modifications to U.S. federal healthcare Anti-Kickback Statute safe harbors, which, among other things, will affect rebates paid by manufacturers to Medicare Part D plans, the purpose of which is to further reduce the cost of drug products to consumers. Although some of these and other proposals may require authorization through

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additional legislation to become effective, members of Congress and the presidential administration have indicated that they will continue to seek new legislative or administrative measures to control drug costs. At the state level, legislatures have increasingly passed legislation and implemented regulations designed to control pharmaceutical and biological product pricing, including price or patient reimbursement constraints, discounts, restrictions on certain product access and marketing cost disclosure and transparency measures, and, in some cases, to encourage importation from other countries and bulk purchasing. Furthermore, the increased emphasis on managed healthcare in the United States and on country and regional pricing and reimbursement controls in the European Union will put additional pressure on product pricing, reimbursement and usage, which may adversely affect our future product sales. These pressures can arise from rules and practices of managed care groups, judicial decisions and governmental laws and regulations related to Medicare, Medicaid and healthcare reform, pharmaceutical reimbursement policies and pricing in general.

In addition, there is significant uncertainty regarding the reimbursement status of newly approved healthcare products. We may need to conduct expensive pharmacoeconomic studies in order to demonstrate the cost-effectiveness of our products. If third-party payors do not consider our products to be cost-effective compared to other therapies, the payors may not cover our products after approved as a benefit under their plans or, if they do, the level of payment may not be sufficient to allow us to sell our products on a profitable basis.

We may be subject to costly product liability or other liability claims and may not be able to obtain adequate insurance.

The use of our drug candidates in clinical trials may result in adverse events. We cannot predict all the possible harms or adverse events that may result from our clinical trials. We currently maintain limited product liability insurance. We may not have sufficient resources to pay for any liabilities resulting from a personal injury or other claim excluded from, or beyond the limit of, our insurance coverage. Our insurance does not cover third parties’ negligence or malpractice, and our clinical investigators and sites may have inadequate insurance or none at all. In addition, in order to conduct clinical trials or otherwise carry out our business, we may have to contractually assume liabilities for which we may not be insured. If we are unable to look to our own insurance or a third party’s insurance to pay claims against us, we may have to pay any arising costs and damages ourselves, which may be substantial.

In addition, if we commercially launch drugs based on our drug candidates, we will face even greater exposure to product liability claims. This risk exists even with respect to those drugs that are approved for commercial sale by the FDA and foreign regulatory agencies and manufactured in licensed and regulated facilities. We intend to secure additional limited product liability insurance coverage for drugs that we commercialize, but may not be able to obtain such insurance on acceptable terms with adequate coverage, or at reasonable costs. Even if we are ultimately successful in product liability litigation, the litigation would consume substantial amounts of our financial and managerial resources and may create adverse publicity, all of which would impair our ability to generate sales of the affected product and our other potential drugs. Moreover, product recalls may be issued at our discretion or at the direction of the FDA and foreign regulatory agencies, other governmental agencies or companies having regulatory control for drug sales. Product recalls are generally expensive and often have an adverse effect on the reputation of the drugs being recalled and of the drug’s developer or manufacturer.

We may be required to indemnify third parties against damages and other liabilities arising out of our development, commercialization and other business activities, which could be costly and time-consuming and distract management. If third parties that have agreed to indemnify us against damages and other liabilities arising from their activities do not fulfill their obligations, then we may be held responsible for those damages and other liabilities.

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Our relationships with customers, healthcare providers, clinical trial sites and professionals and third-party payors will be subject to applicable anti-kickback, fraud and abuse and other laws and regulations. If we fail to comply with federal, state and foreign laws and regulations, including healthcare, privacy and data security laws and regulations, we could face criminal sanctions, civil penalties, contractual damages, reputational harm and diminished profits and future earnings.

Healthcare providers, physicians and third-party payors play a primary role in the recommendation and prescription of any drug candidates for which we may obtain marketing approval. Our arrangements with customers, healthcare providers and professionals and third-party payors may expose us to broadly applicable fraud and abuse and other healthcare laws and regulations that may constrain the business or financial arrangements and relationships through which we develop, and may market, sell and distribute, our products for which we obtain marketing approval. Restrictions under applicable federal and state healthcare laws and regulations, include, but are not limited to, the following:

Efforts to ensure that our business arrangements with third parties will comply with applicable healthcare laws and regulations will involve substantial costs. It is possible that governmental authorities will conclude that

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our business practices may not comply with current or future statutes, regulations or case law involving applicable fraud and abuse or other healthcare laws and regulations. If our operations are found to be in violation of any of these laws or any other governmental regulations that may apply to us, we may be subject to significant civil, criminal and administrative penalties, damages, fines, exclusion from government funded healthcare programs, such as Medicare and Medicaid, and the curtailment or restructuring of our operations. Exclusion, suspension and debarment from government funded healthcare programs would significantly impact our ability to commercialize, sell or distribute any drug. If any of the physicians or other providers or entities with whom we expect to do business are found to be not in compliance with applicable laws, they may be subject to criminal, civil or administrative sanctions, including exclusions from government funded healthcare programs.

The collection, use, disclosure, transfer, or other processing of personal data regarding individuals in the European Union, including personal health data, is subject to the EU General Data Protection Regulation, or the GDPR, which became effective in May 2018. The GDPR, which is wide-ranging in scope, imposes several requirements relating to the control over personal data by individuals to whom the personal data relates, the information provided to the individuals, the documentation we must maintain, the security and confidentiality of the personal data, data breach notification and the use of third-party processors in connection with the processing of personal data. The GDPR also imposes strict rules on the transfer of personal data out of the European Union, provides an enforcement authority and authorizes the imposition of large penalties for noncompliance, including the potential for fines of up to €20 million or 4% of the annual global revenues of the non-compliant company, whichever is greater. The GDPR has increased our responsibility and potential liability in relation to personal data that we process compared to prior European Union law, and we may be required to put in place additional mechanisms to ensure compliance with the GDPR, which could divert management’s attention and increase our cost of doing business. However, despite our ongoing efforts to bring our practices into compliance with the GDPR, we may not be successful either due to various factors within our control or other factors outside our control. It is also possible that local data protection authorities may have different interpretations of the GDPR, leading to potential inconsistencies amongst various European Union Member States. Any failure or alleged failure (including as a result of deficiencies in our policies, procedures or measures relating to privacy, data security, marketing or communications) by us to comply with laws, regulations, policies, legal or contractual obligations, industry standards or regulatory guidance relating to privacy or data security, may result in governmental investigations and enforcement actions, litigation, fines and penalties or adverse publicity. In addition, new regulation, legislative actions or changes in interpretation of existing laws or regulations regarding data privacy and security (together with applicable industry standards) may increase our costs of doing business. We expect that there will continue to be new proposed laws, regulations and industry standards relating to privacy and data protection in the United States, the European Union and other jurisdictions, such as the California Consumer Privacy Act of 2018 that will go into effect beginning January 1, 2020, and we cannot determine the impact such future laws, regulations and standards will have on our business.

Comprehensive U.S. tax reform legislation could increase the tax burden on our orphan drug programs and adversely affect our business and financial condition.

The U.S. government enacted comprehensive tax legislation in 2017, or the 2017 Tax Act, that includes significant changes to the taxation of business entities. These changes include, among others, (i) a permanent reduction to the corporate income tax rate, (ii) a partial limitation on the deductibility of business interest expense and net operating loss carryforwards, (iii) a shift of the U.S. taxation of multinational corporations from a tax on worldwide income to a territorial system (along with certain rules designed to prevent erosion of the U.S. income tax base) and (iv) a one-time tax on accumulated offshore earnings held in cash and illiquid assets, with the latter taxed at a lower rate. Further, the comprehensive tax legislation, among other things, reduces the orphan drug tax credit from 50% to 25% of qualifying expenditures. When and if we become profitable, this reduction in tax credits may result in an increased federal income tax burden on our orphan drug programs as it may cause us to pay federal income taxes earlier under the revised tax law than under the prior law and, despite being partially off-set by a reduction in the corporate tax rate from a top marginal rate of 35% to a flat rate of 21%, may increase our total federal tax liability attributable to such programs.

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Notwithstanding the reduction in the corporate income tax rate, the overall impact of this comprehensive tax legislation resulted in an overall reduction in our deferred tax assets, and our business and financial condition could still be adversely affected as additional guidance and regulations are issued with respect to the original tax law change. In addition, it is uncertain if and to what extent various states will conform to this comprehensive tax legislation. The impact of this comprehensive tax legislation on holders of our common stock is also uncertain and could be adverse. Investors should consult with their legal and tax advisors with respect to this comprehensive tax legislation and the potential tax consequences of investing in or holding our common stock.

Our ability to use net operating loss carryforwards and tax credit carryforwards to offset future taxable income may be subject to certain limitations, and ownership changes may limit our ability to use our net operating losses and tax credits in the future.

Our ability to use our federal and state net operating loss carryforwards, or NOLs, to offset potential future taxable income and reduce related income taxes depends upon our generation of future taxable income. We cannot predict with certainty when, or whether, we will generate sufficient taxable income to use our NOLs.

Our federal NOLs generated prior to 2018 will continue to be governed by tax rules in effect prior to the 2017 Tax Act, with unused NOLs expiring 20 years after we report a tax loss. These NOLs could expire unused and be unavailable to offset future taxable income. We cannot predict if and to what extent various states will conform to the 2017 Tax Act.

In addition, generally, if one or more stockholders or groups of stockholders who owns at least 5% of stock increases its ownership by more than 50% over its lowest ownership percentage within a three-year testing period, an ownership change occurs, or an Ownership Change. Our ability to utilize our NOLs and tax credit carryforwards to reduce taxes payable in a year we have taxable income may be limited if there has been an Ownership Change in our stock. Similar rules may apply under state tax laws. We may experience Ownership Changes in the future as a result of future stock sales or other changes in the ownership of our stock, some of which are beyond our control and, as a result, NOLs generated in 2017 and before, may expire unused.

Any material limitation or expiration of our NOLs and tax credit carryforwards may harm our future net income by effectively increasing our future effective tax rate, which could result in a reduction in the market price of our common stock.

Responding to any claims relating to improper handling, storage or disposal of the hazardous chemicals and radioactive and biological materials we use in our business could be time-consuming and costly.

Our research and development processes involve the controlled use of hazardous materials, including chemicals and radioactive and biological materials. Our operations produce hazardous waste products. We cannot eliminate the risk of accidental contamination or discharge and any resultant injury from those materials. Federal, state and local laws and regulations govern the use, manufacture, storage, handling and disposal of hazardous materials. We may be sued for any injury or contamination that results from our or third parties’ use of these materials. Compliance with environmental laws and regulations is expensive, and current or future environmental regulations may impair our research, development and production activities.

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Our facilities in California are located near an earthquake fault, and an earthquake or other types of natural disasters, catastrophic events or resource shortages could disrupt our operations and adversely affect our results.

All our facilities and our important documents and records, such as hard and electronic copies of our laboratory books and records for our drug candidates and compounds and our electronic business records, are located in our corporate headquarters at a single location in South San Francisco, California near active earthquake zones. If a natural disaster, such as an earthquake, fire or flood, a catastrophic event such as a disease pandemic or terrorist attack, or a localized extended outage of critical utilities or transportation systems occurs, we could experience a significant business interruption. Our partners and other third parties on which we rely may also be subject to business interruptions from such events. In addition, California from time to time has experienced shortages of water, electric power and natural gas. Future shortages and conservation measures could disrupt our operations and cause expense, thus adversely affecting our business and financial results.

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DISCLOSURE REGARDING FORWARD-LOOKING STATEMENTS

This prospectus supplement, the accompanying prospectus, the documents we have filed with the U.S. Securities and Exchange Commission, or SEC, that are incorporated by reference and any free writing prospectus that we have authorized for use in connection with this offering contain forward-looking statements indicating expectations about future performance and other forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended, or Securities Act, Section 21E of the Securities Exchange Act of 1934, as amended, or Exchange Act, and the Private Securities Litigation Reform Act of 1995, that involve risks and uncertainties. We intend that such statements be protected by the safe harbor created thereby. Forward-looking statements involve risks and uncertainties and our actual results and the timing of events may differ significantly from the results discussed in the forward-looking statements. Examples of such forward-looking statements include, but are not limited to, statements about or relating to:

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Such forward-looking statements involve risks and uncertainties, including, but not limited to:

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In addition, such statements are subject to the risks and uncertainties discussed in the “Risk Factors” section of this document, and the risks and uncertainties discussed elsewhere in this prospectus supplement and the accompanying prospectus, as well as documents incorporated herein and therein by reference. Such statements speak only as of the date on which they are made, and, except as required by law, we undertake no obligation to update any forward-looking statement to reflect events or circumstances after the date on which the statement is made or to reflect the occurrence of unanticipated events. New factors emerge from time to time, and it is not possible for us to predict which factors will arise. In addition, we cannot assess the impact of each factor on our business or the extent to which any factor, or combination of factors, may cause actual results to differ materially from those contained in any forward-looking statements.

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USE OF PROCEEDS

We estimate that the net proceeds from this offering will be approximately $115.9 million, or approximately $133.4 million if the underwriters exercise in full their over-allotment option, after deducting underwriting discounts and commissions and estimated offering expenses payable by us.

We intend to use the net proceeds from this offering, if completed, to fund:

We intend to use approximately $11.6 million of the net proceeds from this offering to pay the cost of the capped call transaction as described in “Description of Capped Call Transactions.”

If the underwriters exercise their over-allotment option, we expect to use a portion of the net proceeds from the sale of the additional notes to enter into an additional capped call transaction with the capped call counterparty and any remainder of the net proceeds for the reasons stated above.

Based on the planned use of proceeds described above, we believe that the net proceeds from this offering and our current cash and cash equivalents, will be sufficient to enable us to fund our operating expenses and capital expenditure requirements for the next two to three years, depending on our development activities, including potentially delaying the planned Phase 3 clinical trial of reldesemtiv in patients with ALS. We have based this estimate on assumptions that may prove to be incorrect, and we could use our available capital resources sooner than we currently expect.

Due to the uncertainties inherent in the product development process, it is difficult to estimate with certainty the exact amounts of the net proceeds from this offering that may be used for the above purposes. Our management will have broad discretion over the use of the net proceeds from this offering. The amounts and timing of our expenditures will depend upon numerous factors including the results of our research and development efforts, the timing and success of preclinical studies and any ongoing clinical trials or clinical trials we may commence in the future, the timing of regulatory submissions and the amount of cash obtained through future collaborations, if any.

The Term Loan matures on December 1, 2023 and bears interest at a rate equal to the greater of (i) 8.05% and (ii) the sum (a) the 30-day U.S. LIBOR rate on the last business day of the month that immediately precedes the month in which interest will accrue, plus (b) 6.81%. We entered into the Term Loan on May 17, 2019 and used the proceeds thereof to repay a prior term loan facility with Oxford Finance LLC and Silicon Valley Bank. See “Description of Other Indebtedness”

Pending application of the net proceeds as described above, we intend to invest the net proceeds in a variety of capital-preservation instruments, including direct or guaranteed obligations of the U.S. government, certificates of deposit and money market funds, in accordance with our investment policy.

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DIVIDEND POLICY

We have never declared or paid dividends on our capital stock and do not intend to pay cash dividends on our capital stock in the foreseeable future. Additionally, any cash dividends declared or paid would require prior written consent under the terms of the Term Loan.

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CAPITALIZATION

The following table presents our cash and cash equivalents and our capitalization as of September 30, 2019:

This table should be read in conjunction with the other information in this prospectus supplement and the accompanying prospectus and the documents that are incorporated by reference herein and therein, including our consolidated financial statements and related notes.

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The number of shares of common stock, actual and as adjusted, shown in the table above excludes the following at September 30, 2019:

The number of shares of our common stock to be outstanding immediately after this offering as shown above does not include the up to $48.8 million of shares of our common stock that remained available for sale as of September 30, 2019 under our Controlled Equity Offering^SM Sales Agreement, or the Sales Agreement, that we entered into with Cantor Fitzgerald & Co. as of March 6, 2019. Between September 30, 2019 and the date of this prospectus supplement, no shares were sold under the Sales Agreement.

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DESCRIPTION OF NOTES

We will issue the notes under an indenture and a supplemental indenture (together, the “indenture”), each between us and U.S. Bank National Association, as trustee (the “trustee”), and to be dated as of the initial closing date of this offering.

The following is a summary of certain provisions of the notes and the indenture. It is only a summary and is not complete. We qualify this summary by referring you to the indenture and the notes, because they, and not this summary, define your rights as a holder of the notes. We will provide you with a copy of the indenture, which includes the form of the notes, as provided under the caption “Where You Can Find Additional Information.”

In addition, the indenture and the notes will be deemed to include certain terms that are made a part of the indenture and the notes pursuant to the Trust Indenture Act of 1939, as amended (the “Trust Indenture Act”).

Certain terms used in this summary are defined below under the caption “—Definitions.” Certain other terms used in this summary are defined in the indenture.

This “Description of Notes” section supplements and, to the extent inconsistent therewith, supersedes the information in the accompanying prospectus under the caption “Description of Debt Securities.”

References to “we,” “us” and “our” in this section refer to Cytokinetics, Incorporated only and not to any of its subsidiaries. References to any “note” in this section refer to any authorized denomination of a note, unless the context requires otherwise.

Generally

The notes will:

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The indenture will not contain any financial covenants and will not limit us or our subsidiaries from incurring additional indebtedness, paying dividends or issuing or repurchasing any securities. Except to the extent described below under the captions “—Conversion Rights—Increase in Conversion Rate in Connection with a Make-Whole Fundamental Change,” “—Fundamental Change Permits Noteholders to Require Us to Repurchase Notes” and “—Consolidation, Merger and Asset Sale,” the indenture will not contain any provisions designed to protect noteholders upon a highly leveraged transaction involving us or a decline in our credit rating as a result of a recapitalization, takeover, highly leveraged transaction or other restructuring involving us.

Without the consent of any noteholder, we may issue additional notes under the indenture with the same terms as the notes we are offering (except for certain differences, such as the date as of which interest begins to accrue and the first interest payment date for such additional notes). However, such additional notes must be identified by a separate CUSIP number or by no CUSIP number if they are not fungible, for federal income tax or federal securities laws purposes, with other notes we issue under the indenture.

We do not intend to list the notes on any securities exchange or include them in any automated inter-dealer quotation system.

Absent manifest error, a person in whose name a note is registered on the registrar’s books will be considered to be the holder of that note for all purposes, and only registered noteholders (which, in the case of notes held through DTC, will initially be DTC’s nominee, Cede & Co.) will have rights under the indenture as noteholders.

Subject to applicable law, we or our subsidiaries may directly or indirectly repurchase notes in the open market or otherwise, whether through private or public tender or exchange offers, cash-settled swaps or other cash-settled derivatives. The indenture requires us to promptly deliver to the trustee for cancellation all notes that we or our subsidiaries have purchased or otherwise acquired.

Payments on the Notes

For purposes of the notes, the description below under this section titled “—Payments on the Notes” supersedes the information in the accompanying prospectus under the caption “Description of Debt Securities—Payment and Paying Agents.”

We will pay (or cause the paying agent to pay) the principal of, and interest on, any global note by wire transfer of immediately available funds. We will pay (or cause the paying agent to pay) the principal of, and interest on, any certificated note as follows:

To be timely, a written request referred to in the first bullet point above must be delivered no later than the “close of business” (as defined below under the caption “—Definitions”) on the following date: (i) with respect

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to the payment of any interest due on an interest payment date, the immediately preceding record date; and (ii) with respect to any other payment, the date that is 15 calendar days immediately before the date such payment is due.

If the due date for a payment on a note is not a “business day” (as defined below under the caption “—Definitions”), then such payment may be made on the immediately following business day and no interest will accrue on such payment as a result of the related delay. Solely for purposes of the immediately preceding sentence, a day on which the applicable place of payment is authorized or required by law or executive order to close or be closed will be deemed not to be a “business day.”

Registrar, Paying Agent and Conversion Agent

We will maintain one or more offices or agencies in the continental United States where notes may be presented for registration of transfer or for exchange, payment and conversion, which we refer to as the “registrar,” “paying agent” and “conversion agent,” respectively. We have appointed the trustee as the initial registrar, paying agent and conversion agent and its office in the United States as a place where notes may be presented for payment. However, we may change the registrar, paying agent and conversion agent, and we or any of our subsidiaries may choose to act in that capacity as well, without prior notice to the noteholders.

Transfers and Exchanges

For purposes of the notes, the description below under this section titled “—Transfers and Exchanges” supersedes the information in the accompanying prospectus under the caption “Description of Debt Securities—Form, Exchange and Transfer.”

A noteholder may transfer or exchange its notes at the office of the registrar in accordance with the indenture. We, the trustee and the registrar may require the noteholder to, among other things, deliver appropriate endorsements or transfer instruments, and such certificates or other documentation or evidence as we or they may reasonably require to determine that such transfer or exchange complies with applicable securities laws. The notes and any shares issued upon conversion of the notes are subject to transfer restrictions, which are described below under the caption “Transfer Restrictions.” In addition, we, the trustee and the registrar may refuse to register the transfer or exchange of any note that is subject to conversion, redemption or required repurchase.

We have appointed the trustee’s office in the United States as a place where notes may be presented for registration of transfer or for exchange. However, we may change the registrar or act as the registrar ourselves without prior notice to the noteholders.

Interest

The notes will bear cash interest at an annual rate of 4.00%, payable semi-annually in arrears on May 15 and November 15 of each year, beginning on May 15, 2020, to the noteholders of record of the notes as of the close of business on the immediately preceding May 1 and November 1, respectively. Interest will accrue from, and including, the last date to which interest has been paid or duly provided for (or, if no interest has been paid or duly provided for, from, and including, the date the notes are initially issued) to, but excluding, the next interest payment date. Interest will be computed on the basis of a 360-day year comprised of twelve 30-day months.

In addition to the stated interest on the notes referred to above, special interest will accrue on the notes in the circumstances described below under the caption “—Events of Default—Special Interest as Sole Remedy for Certain Reporting Defaults.” All references in this prospectus supplement to interest on the notes include any special interest payable on the notes, unless the context requires otherwise.

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Ranking

The notes will be our general unsecured obligations that will:

The indenture will not prohibit us from incurring additional indebtedness, including secured indebtedness, which would be effectively senior to the notes to the extent of the value of the collateral securing that indebtedness, or indebtedness that would rank equal in right of payment with the notes. The indenture will also not prohibit our subsidiaries from incurring any additional indebtedness or other liabilities that would be structurally senior to our obligations under the notes.

In the event of our bankruptcy, liquidation, reorganization or other winding up, our assets that secure any indebtedness will not be available to make payments under the notes unless all of that indebtedness is first paid in full. We advise you that there may not be sufficient assets remaining to pay amounts due on any or all the notes then outstanding. In the event of the bankruptcy, liquidation, reorganization or other winding up of any of our subsidiaries, we, as a common equity holder of that subsidiary, and, therefore, the noteholders, will rank behind that subsidiary’s creditors, including that subsidiary’s trade creditors, and (to the extent we are not a holder thereof) that subsidiary’s preferred equity holders. Even if we were a creditor of any of our subsidiaries, our rights as a creditor would be effectively subordinated to any security interest of others in the assets of that subsidiary, to the extent of the value of those assets, and would be subordinated to any indebtedness of that subsidiary that is senior in right of payment to that held by us.

Our subsidiaries will have no obligations under the notes. The ability of our subsidiaries to pay dividends or make other payments to us is restricted by, among other things, corporate and other laws and by agreements to which our subsidiaries may become a party. Accordingly, we may be unable to gain access to the cash flow or assets of our subsidiaries to enable us to make payments on the notes.

As of September 30, 2019, we had $45 million aggregate principal amount of indebtedness, all of which was senior secured indebtedness under the Term Loan. After giving effect to the issuance of the notes (assuming no exercise of the underwriters’ over-allotment option), our total consolidated indebtedness for borrowed money would have been approximately $165 million in principal amount.

Optional Redemption

We may not redeem the notes at our option at any time before November 20, 2023. Subject to the terms of the indenture, we have the right, at our election, to redeem all, or any portion in an authorized denomination, of the notes, at any time and from time to time, on a redemption date occurring on or after November 20, 2023 and, in the case of any partial redemption, on or before the 60th “scheduled trading day” (as defined below under the caption “—Definitions”) immediately before the maturity date, for cash, but only if the “last reported sale price” (as defined below under the caption “—Definitions”) per share of common stock exceeds 130% of the “conversion price” (as defined below under the caption “—Definitions”) on (i) each of at least 20 “trading days” (as defined below under the caption “—Definitions”), whether or not consecutive, during the 30 consecutive trading days ending on, and including, the trading day immediately before the date we send the related

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redemption notice; and (ii) the trading day immediately before the date we send such notice. In addition, calling any note for redemption will constitute a “make-whole fundamental change” (as defined below under the caption “—Definitions”) with respect to that note, in which case the conversion rate applicable to the conversion of that note will be increased in certain circumstances if the conversion date for such note occurs during the period from, and including, the date the Company gives the related redemption notice to, and including, the business day immediately before the related redemption date. If we elect to redeem less than all of the outstanding notes, then the redemption will not constitute a make-whole fundamental change with respect to the notes not called for redemption, and holders of the notes not called for redemption will not be entitled to an increased conversion rate for such notes as described above on account of the redemption, except to the limited extent described below under the caption “—Conversion Rights—When the Notes May Be Converted—Conversion upon Redemption.”

The redemption date will be a business day of our choosing that is no more than 85, nor less than 65, scheduled trading days after the date we send the related redemption notice, as described below.

The redemption price for any note called for redemption will be the principal amount of such note plus accrued and unpaid interest on such note to, but excluding, the redemption date. However, if the redemption date is after a regular record date and on or before the next interest payment date, then (i) the holder of such note at the close of business on such regular record date will be entitled, notwithstanding such redemption, to receive, on or, at our election, before such interest payment date, the unpaid interest that would have accrued on such note to, but excluding, such interest payment date; and (ii) the redemption price will not include accrued and unpaid interest on such note to, but excluding, such redemption date.

We will send to each noteholder notice of the redemption containing certain information set forth in the indenture, including the redemption price and the redemption date.

Notes called for redemption must be delivered to the paying agent (in the case of certificated notes) or the “depositary procedures” (as defined below under the caption “—Definitions”) must be complied with (in the case of global notes) for the holder of those notes to be entitled to receive the redemption price.

If only a portion of a note is subject to redemption and that note is converted in part, then the converted portion of that note will be deemed to be from the portion of that note that was subject to redemption.

Notwithstanding anything to the contrary above, we may not redeem any notes if the principal amount of the notes has been accelerated (other than as a result of a failure to make the payment of the related redemption price and any related interest described above on the redemption date) and such acceleration has not been rescinded on or before the redemption date.

Conversion Rights

Generally

The notes (or any portion of a note in an authorized denomination) will be convertible in the circumstances described below, at the noteholders’ option, into cash, shares of our common stock or a combination of cash and shares of our common stock (together with cash in lieu of any fractional share, if applicable), at our election, based on an initial conversion rate of 94.7811 shares per $1,000 principal amount of notes (which represents an initial conversion price of approximately $10.55 per share).

Noteholders may convert their notes only in the circumstances described below under the caption “—When the Notes May Be Converted.”

Treatment of Interest upon Conversion

We will not adjust the conversion rate to account for any accrued and unpaid interest on any note being converted, and, except as described below, our delivery of the consideration due in respect of the conversion will

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be deemed to fully satisfy and discharge our obligation to pay the principal of, and accrued and unpaid interest, if any, on, such note. As a result, except as described below, any accrued and unpaid interest on a converted note will be deemed to be paid in full rather than cancelled, extinguished or forfeited. In addition, if the consideration due upon conversion consists of both cash and shares of our common stock, then accrued and unpaid interest that is deemed to be paid therewith will be deemed to be paid first out of such cash.

Notwithstanding anything to the contrary above, if the conversion date of a note is after a regular record date and before the next interest payment date, then:

However, such noteholder need not deliver such cash:

Accordingly, for the avoidance of doubt, all noteholders as of the close of business on the regular record date immediately before the maturity date will receive the full interest payment that would have been due on the maturity date regardless of whether their notes have been converted after such regular record date.

When the Notes May Be Converted

Noteholders may convert their notes only in the circumstances set forth below. However, in no event may notes be converted after the close of business on the scheduled trading day immediately before the maturity date.

Conversion upon Satisfaction of Common Stock Sale Price Condition

Prior to the close of business on the business day immediately preceding July 15, 2026, a noteholder may convert its notes during any calendar quarter commencing after the calendar quarter ending on March 31, 2020 (and only during such calendar quarter), if the last reported sale price per share of our common stock for each of at least 20 trading days, whether or not consecutive, during the period of 30 consecutive trading days ending on, and including, the last trading day of the immediately preceding calendar quarter exceeds 130% of the conversion price on the applicable trading day.

Conversion upon Satisfaction of Note Trading Price Condition

Prior to the close of business on the business day immediately preceding July 15, 2026, a noteholder may convert its notes during the five consecutive business days immediately after any 10 consecutive trading day period (such 10 consecutive trading day period, the “measurement period”) if the “trading price” (as defined below under the caption “—Definitions”) per $1,000 principal amount of notes, as determined following a request by a noteholder in accordance with the procedures described below, for each trading day of the

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measurement period was less than 98% of the product of the last reported sale price per share of our common stock on such trading day and the conversion rate on such trading day. We refer to this condition as the “trading price condition.”

The trading price will be determined by the bid solicitation agent as described below and the definition of “trading price.” The bid solicitation agent (if not us) will have no obligation to determine the trading price of the notes unless we have requested such determination, and we will have no obligation to make such request (or seek bids ourselves) unless a noteholder of at least $5.0 million aggregate principal amount of notes (or such lesser principal amount as may be then outstanding) provides us with reasonable evidence that the trading price per $1,000 principal amount of notes would be less than 98% of the product of the last reported sale price per share of our common stock and the conversion rate. If such a noteholder provides such evidence, then we will instruct the bid solicitation agent to (or, if we are acting as the bid solicitation agent, we will) determine the trading price of the notes beginning on the next trading day and on each successive trading day until the trading price per $1,000 principal amount of notes is greater than or equal to 98% of the product of the last reported sale price per share of our common stock on such trading day and the conversion rate on such trading day. If the trading price condition has been met as described above, then we will notify the noteholders and the trustee of the same, and each of the noteholders and the trustee will be entitled to rely conclusively upon the accuracy of such notice and any calculations therein without independent verification. If, on any trading day after the trading price condition has been met as described above, the trading price per $1,000 principal amount of notes is greater than or equal to 98% of the product of the last reported sale price per share of our common stock on such trading day and the conversion rate on such trading day, then we will notify the noteholders and the trustee of the same, and, thereafter, neither we nor the bid solicitation agent will be required to solicit bids again until another noteholder request is made as described above.

We will act as the initial bid solicitation agent. However, we may change the bid solicitation agent, and we may appoint any of our subsidiaries to act in that capacity as well, without prior notice to the noteholders.

Conversion upon Specified Corporate Events

Certain Distributions

If, prior to the close of business on the business day immediately preceding July 15, 2026, we elect to:

then, in either case, we will send notice of such distribution, and of the related right to convert notes, to noteholders and the trustee at least 65 scheduled trading days before the “ex-dividend date” (as defined below under the caption “—Definitions”) for such distribution (or, if later in the case of any such separation of rights

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issued pursuant to a stockholder rights plan or the occurrence of any such triggering event under a stockholder rights plan, as soon as reasonably practicable after we become aware of that such separation or triggering event has occurred or will occur). Once we have sent such notice, noteholders may convert their notes at any time until the earlier of the close of business on the business day immediately before such ex-dividend date and our announcement that such distribution will not take place.

Noteholders may not convert their notes pursuant to the provision described in the preceding paragraph on account of any distribution if each noteholder participates, at the same time and upon the same terms as holders of our common stock and solely as a result of holding notes, in such distribution without having to convert its notes as if such noteholder held a number of shares of common stock equal to the conversion rate in effect on the record date for such distribution, multiplied by the principal amount (expressed in thousands) of notes held by such noteholder as of such record date.

Certain Corporate Events

If, prior to the close of business on the business day immediately preceding July 15, 2026, a fundamental change, “make-whole fundamental change” (other than a make-whole fundamental change pursuant to clause (ii) of the definition thereof) or “common stock change event” (as defined below under the caption “—Effect of Common Stock Change Event”) (other than a common stock change event that is solely for the purpose of changing our jurisdiction of incorporation and that (x) does not constitute a fundamental change or a make-whole fundamental change and (y) results in a reclassification, conversion or exchange of outstanding shares of our common stock solely into shares of common stock of the surviving entity and such common stock becomes the “reference property” (as defined below under the caption “—Effect of Common Stock Change Event”) for the notes) occurs, then, in each case, noteholders may convert their notes at any time from, and including, the effective date of such transaction or event to, and including, the 35th trading day after such effective date (or, if such transaction or event also constitutes a fundamental change (other than an “exempted fundamental change,” as defined below under the caption “—Fundamental Change Permits Noteholders to Require Us to Repurchase Notes—No Repurchase Right in Certain Circumstances”), to, and including, the business day immediately before the related fundamental change repurchase date). No later than the second business day after the effective date of any fundamental change, make-whole fundamental change (other than a make-whole fundamental change pursuant to clause (ii) of the definition thereof) or common stock change event that occurs before the maturity date, we will send notice to the noteholders and the trustee of such transaction or event, such effective date and, if applicable, the related right to convert notes.

Conversion upon Redemption

If we call any note for redemption, then the holder of such note may convert such note at any time before the close of business on the business day immediately before the related redemption date (or, if we fail to pay the redemption price due on such redemption date in full, at any time until such time as we pay such redemption price in full).

If we elect to redeem less than all of the outstanding notes, and the holder of any note, or any owner of a beneficial interest in any global note, is reasonably not able to determine, before the close of business on the 62nd scheduled trading day immediately before the relevant redemption date, whether such note or beneficial interest, as applicable, is to be redeemed pursuant to such redemption, then such holder or owner, as applicable, will be entitled to convert such note or beneficial interest, as applicable, at any time before the close of business on the business day immediately before such redemption date, and each such conversion will be deemed to be of a note called for redemption for purposes of the provisions described in this “—Conversion upon Redemption” section, the redemption provisions described above under the caption “—Optional Redemption” and the provisions described below under the caption “—Increase in Conversion Rate in Connection with a Make-Whole Fundamental Change.”

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Conversions During Free Convertibility Period

A noteholder may convert its notes at any time from, and including, July 15, 2026 until the close of business on the scheduled trading day immediately before the maturity date.

Conversion Procedures

To convert a beneficial interest in a global note, the owner of the beneficial interest must:

To convert all or a portion of a physical note, the holder of such note must:

Notes may be surrendered for conversion only after the “open of business” (as defined below under the caption “—Definitions”) and before the close of business on a day that is a business day.

We will pay any documentary, stamp or similar issue or transfer tax or duty due on the issue of any shares of our common stock upon conversion, except any tax or duty that is due because the converting noteholder requests those shares to be registered in a name other than the noteholder’s name.

We refer to the first business day on which the requirements described above to convert a note are satisfied as the “conversion date.”

If a noteholder has validly delivered a “fundamental change repurchase notice” (as defined below under the caption “—Fundamental Change Permits Noteholders to Require Us to Repurchase Notes”) with respect to a note, then such note may not be converted, except to the extent such notice is withdrawn in accordance with the procedures described below.

Settlement upon Conversion

Generally

Upon conversion, we may choose to pay or deliver, as applicable, either cash (“cash settlement”), shares of our common stock (“physical settlement”) or a combination of cash and shares of our common stock (“combination settlement”), as described below. We refer to each of these settlement methods as a “settlement method.” If cash settlement or combination settlement applies to a conversion, then the consideration due will be determined over an “observation period” (as defined below under the caption “—Definitions”) consisting of 60 “VWAP trading days” (as defined below under the caption “—Definitions”).

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Settlement Method

We will have the right, as described below, to elect the settlement method applicable to the conversion of any notes. Except as described below, we must use the same settlement method for all conversions with a conversion date that occurs on the same day, but we will not be obligated to use the same settlement method for conversions with conversion dates that occur on different days. All conversions with a conversion date that occurs on or after July 15, 2026 will be settled using the same settlement method, and we will send notice of such settlement method to noteholders and the conversion agent no later than the close of business on the scheduled trading day immediately before July 15, 2026. If we elect a settlement method for a conversion with a conversion date that occurs before July 15, 2026, then we will send notice of such settlement method to the converting noteholder and the conversion agent no later than the close of business on the business day immediately after the conversion date. However, notwithstanding anything to the contrary above, if we call any notes for redemption, then (i) we will specify in the related redemption notice the settlement method that will apply to all conversions with a conversion date that occurs on or after the date we send such redemption notice and on or before the business day immediately before the related redemption date; and (ii) if the related redemption date is on or after July 15, 2026, then such settlement method must be the same settlement method that applies to all conversions with a conversion date that occurs on or after July 15, 2026.

If we do not timely elect a settlement method with respect to any conversion, then we will be deemed to have elected the “default settlement method” (as defined below). If we timely elect combination settlement with respect to a conversion but do not timely notify the converting noteholder of the applicable “specified dollar amount” (as defined below under the caption “—Definitions”), then the specified dollar amount for such conversion will be deemed to be $1,000 per $1,000 principal amount of notes. For the avoidance of doubt, our failure to timely elect a settlement method or specify the applicable specified dollar amount will not constitute a default under the indenture. We currently intend to settle conversions through combination settlement with a specified dollar amount of $1,000 per $1,000 principal amount of notes.

The “default settlement method” will initially be combination settlement with a specified dollar amount of $1,000 per $1,000 principal amount of notes. However, we may, from time to time, change the default settlement method by sending notice of the new default settlement method to the noteholders. In addition, we may, by notice to the noteholders, irrevocably fix the settlement method, to any settlement method that we are then permitted to elect, that will apply to all note conversions with a conversion date that is on or after the date we send such notice. For the avoidance of doubt, such an irrevocable election, if made, will be effective without the need to amend the indenture or the notes, including pursuant to the provisions described in the seventh bullet point of the fourth paragraph under the caption “—Modification and Amendment” below. However, we may nonetheless choose to execute such an amendment at our option.

Consideration Due upon Conversion

The consideration due upon conversion of each $1,000 principal amount of a note will be as follows:

However, in lieu of delivering any fractional share of common stock otherwise due upon conversion, we will pay cash based on (i) the daily VWAP on the applicable conversion date (or, if such conversion date is not a VWAP trading day, the immediately preceding VWAP trading day), in the case of physical settlement; or (ii) the daily VWAP on the last VWAP trading day of the applicable observation period, in the case of combination settlement.

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If a noteholder converts more than one note on a conversion date, then the consideration due upon such conversion will (in the case of any global note, to the extent permitted by, and practicable under, the depositary procedures) be computed based on the total principal amount of notes converted on such conversion date by that noteholder.

Delivery of the Conversion Consideration

Except as described below under the captions “—Conversion Rate Adjustments” and “—Effect of Common Stock Change Event,” we will pay or deliver, as applicable, the consideration due upon conversion as follows: (i) if cash settlement or combination settlement applies, on or before the second business day immediately after the last VWAP trading day of such observation period; and (ii) if physical settlement applies, on or before the second business day immediately after such conversion date.

When Converting Noteholders Become Stockholders of Record

The person in whose name any share of common stock is issuable upon conversion of any note will be deemed to become the holder of record of that share as of the close of business on (i) the conversion date for such conversion, in the case of physical settlement; or (ii) the last VWAP trading day of the observation period for such conversion, in the case of combination settlement.

Conversion Rate Adjustments

Generally

The conversion rate will be adjusted for the events described below. However, we are not required to adjust the conversion rate for these events (other than a stock split or combination or a tender or exchange offer) if each noteholder participates, at the same time and on the same terms as holders of our common stock, and solely by virtue of being a holder of notes, in such transaction or event without having to convert such noteholder’s notes and as if such noteholder held a number of shares of our common stock equal to the product of (i) the conversion rate in effect on the related record date; and (ii) the aggregate principal amount (expressed in thousands) of notes held by such noteholder on such date.

where:

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Each adjustment to the conversion rate made pursuant to the preceding sentence will become effective at the time set forth in the definition of CR₁ above. If any dividend, distribution, stock split or stock combination of the type described in this paragraph (1) is declared or announced, but not so paid or made, then the conversion rate will be readjusted, effective as of the date our “board of directors” (as defined below under the caption “—Definitions”) determines not to pay such dividend or distribution or to effect such stock split or stock combination, to the conversion rate that would then be in effect had such dividend, distribution, stock split or stock combination not been declared or announced.

where:

Each adjustment to the conversion rate made pursuant to the preceding sentence will become effective at the time set forth in the definition of CR₁ above. To the extent that shares of our common stock are not delivered after the expiration of such rights, options or warrants (including as a result of such rights, options or warrants not being exercised), the conversion rate will be readjusted to the conversion rate that would then be in effect had the increase to the conversion rate for such distribution been made on the basis of delivery of only the number of shares of our common stock actually delivered upon exercise of such rights, option or warrants. To the extent such rights, options or warrants are not so distributed, the conversion rate will be readjusted to the conversion rate that would then be in effect had the ex-dividend date for the distribution of such rights, options or warrants not occurred.

For purposes of this paragraph (2) and the provisions described above under the caption “—When the Notes May Be Converted—Conversion upon Specified Corporate Events—Certain Distributions,” in determining whether any rights, options or warrants entitle holders of our common stock to subscribe for or purchase shares of our common stock at a price per share that is less than the average of the last reported sale prices per share of our common stock for the 10 consecutive trading days ending on, and including, the trading day immediately before the date the distribution of such rights, options or warrants is announced, and in determining the aggregate price payable to exercise such rights, options or warrants, there will be taken into account any consideration we receive for such rights, options or

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warrants and any amount payable on exercise thereof, with the value of such consideration, if not cash, to be determined by us in good faith.

then the conversion rate will be increased based on the following formula:

where:

Each adjustment to the conversion rate made pursuant to the preceding sentence will become effective at the time set forth in the definition of CR₁ above. If FMV is equal to or greater than SP, then, in lieu of the foregoing adjustment to the conversion rate, each noteholder will receive, for each $1,000 principal amount of notes held by such noteholder on the record date for such distribution, at the same time and on the same terms as holders of our common stock, the amount and kind of shares of capital stock, evidences of indebtedness, assets, property, rights, options or warrants that such noteholder would have received if such noteholder had owned, on such record date, a number of shares of our common stock equal to the conversion rate in effect on such record date.

To the extent such distribution is not so paid or made, the conversion rate will be readjusted to the conversion rate that would then be in effect had the adjustment been made on the basis of only the distribution, if any, actually made or paid.

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where:

The adjustment to the conversion rate pursuant to this paragraph (3)(b) will be calculated as of the close of business on the last trading day of the spin-off valuation period but will be given effect immediately after the open of business on the ex-dividend date for the spin-off, with retroactive effect. If a note is converted and the conversion date (in the case of physical settlement) or any VWAP trading day of the applicable observation period (in the case of cash settlement or combination settlement) occurs during the spin-off valuation period, then, notwithstanding anything to the contrary, we will, if necessary, delay the settlement of such conversion until the second business day after the last day of the spin-off valuation period.

To the extent any dividend or distribution of the type described above in this paragraph (3)(b) is declared but not made or paid, the conversion rate will be readjusted to the conversion rate that would then be in effect had the adjustment been made on the basis of only the dividend or distribution, if any, actually made or paid.

where:

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Each adjustment to the conversion rate made pursuant to the preceding sentence will become effective at the time set forth in the definition of CR₁ above. If D is equal to or greater than SP, then, in lieu of the foregoing adjustment to the conversion rate, each noteholder will receive, for each $1,000 principal amount of notes held by such noteholder on the record date for such dividend or distribution, at the same time and on the same terms as holders of our common stock, the amount of cash that such noteholder would have received if such noteholder had owned, on such record date, a number of shares of our common stock equal to the conversion rate in effect on such record date. To the extent such dividend or distribution is declared but not made or paid, the conversion rate will be readjusted to the conversion rate that would then be in effect had the adjustment been made on the basis of only the dividend or distribution, if any, actually made or paid.

where:

provided, however, that the conversion rate will in no event be adjusted down pursuant to the provisions described in this paragraph (5), except to the extent provided in the immediately following

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paragraph. The adjustment to the conversion rate pursuant to this paragraph (5) will be calculated as of the close of business on the last trading day of the tender/exchange offer valuation period but will be given effect immediately after the expiration time, with retroactive effect. If a note is converted and the conversion date (in the case of physical settlement) or any VWAP trading day of the applicable observation period (in the case of cash settlement or combination settlement) occurs on the expiration date or during the tender/exchange offer valuation period, then, notwithstanding anything to the contrary, we will, if necessary, delay the settlement of such conversion until the second business day after the last day of the tender/exchange offer valuation period.

To the extent such tender or exchange offer is announced but not consummated (including as a result of being precluded from consummating such tender or exchange offer under applicable law), or any purchases or exchanges of shares of common stock in such tender or exchange offer are rescinded, the conversion rate will be readjusted to the conversion rate that would then be in effect had the adjustment been made on the basis of only the purchases or exchanges of shares of common stock, if any, actually made, and not rescinded, in such tender or exchange offer.

We will not be required to adjust the conversion rate except as described above or below under the caption “—Increase in Conversion Rate in Connection with a Make-Whole Fundamental Change.” Without limiting the foregoing, we will not be required to adjust the conversion rate on account of:

The Deferral Exception

If an adjustment to the conversion rate otherwise required by the provisions described above would result in a change of less than 1% to the conversion rate, then, notwithstanding anything to the contrary described above, we may, at our election, defer and carry forward such adjustment, except that all such deferred adjustments must be given effect immediately upon the earliest to occur of the following: (i) when all such deferred adjustments would result in an aggregate change of at least 1% to the conversion rate; (ii) the conversion date of any note (in the case of physical settlement) or the first VWAP trading day of any observation period of any note (in the case of cash settlement or combination settlement); (iii) the date a fundamental change or make-whole fundamental change (other than a make-whole fundamental change pursuant to clause (ii) of the definition thereof) occurs; (iv) the date we call any notes for redemption; and (v) July 15, 2026. We refer to our ability to defer adjustments as described above as the “deferral exception.”

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Notice of Conversion Rate Adjustments

Upon the effectiveness of any adjustment to the conversion rate pursuant to the provisions described above under the caption “—Conversion Rate Adjustments—Generally,” we will promptly send notice to the noteholders and the trustee containing (i) a brief description of the transaction or other event on account of which such adjustment was made; (ii) the conversion rate in effect immediately after such adjustment; and (iii) the effective time of such adjustment.

Voluntary Conversion Rate Increases

To the extent permitted by law and applicable stock exchange rules, we, from time to time, may (but are not required to) increase the conversion rate by any amount if (i) our board of directors determines that such increase is in our best interest or that such increase is advisable to avoid or diminish any income tax imposed on holders of our common stock or rights to purchase our common stock as a result of any dividend or distribution of shares (or rights to acquire shares) of our common stock or any similar event; (ii) such increase is in effect for a period of at least 20 business days; and (iii) such increase is irrevocable during such period.

Tax Considerations

For a discussion of the U.S. federal income tax treatment of an adjustment to the conversion rate, see “Certain Material U.S. Federal Income Tax Considerations.”

Special Provisions for Adjustments that Are Not Yet Effective and Where Converting Noteholders Participate in the Relevant Transaction or Event

Notwithstanding anything to the contrary, if:

then, solely for purposes of such conversion, we will, without duplication, give effect to such adjustment on such conversion date (in the case of physical settlement) or such VWAP trading day (in the case of combination settlement), and, for the avoidance of doubt, such shares will not be entitled to participate in such event. In such case, if the date we are otherwise required to deliver the consideration due upon such conversion is before the first date on which the amount of such adjustment can be determined, then we will delay the settlement of such conversion until the second business day after such first date.

Notwithstanding anything to the contrary in the indenture or the notes, if:

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then (x) such conversion rate adjustment will not be given effect for such conversion (in the case of physical settlement) or for such VWAP trading day (in the case of combination settlement); and (y) the shares of common stock, if any, issuable upon such conversion (in the case of physical settlement) or issuable with respect to such VWAP trading day (in the case of combination settlement) based on such unadjusted conversion rate will be entitled to participate in such dividend or distribution.

Stockholder Rights Plans

If any shares of our common stock are to be issued upon conversion of any note and, at the time of such conversion, we have in effect any stockholder rights plan, then the holder of that note will be entitled to receive, in addition to, and concurrently with the delivery of, the consideration otherwise due upon such conversion, the rights set forth in such stockholder rights plan, unless such rights have separated from our common stock at such time, in which case, and only in such case, the conversion rate will be adjusted pursuant to the provisions described above in paragraph (3)(a) under the caption “—Conversion Rate Adjustments—Generally” on account of such separation as if, at the time of such separation, we had made a distribution of the type referred to in such paragraph to all holders of our common stock, subject to readjustment as described above if such rights expire, terminate or are redeemed. We currently do not have a stockholder rights plan in effect.

Increase in Conversion Rate in Connection with a Make-Whole Fundamental Change

Generally

If a make-whole fundamental change occurs and the conversion date for the conversion of a note occurs during the related “make-whole fundamental change conversion period” (as defined below under the caption “—Definitions”), then, subject to the provisions described below, the conversion rate applicable to such conversion will be increased by a number of shares (the “additional shares”) set forth in the table below corresponding (after interpolation as described below) to the “make-whole fundamental change effective date” (as defined below under the caption “—Definitions”) and the “stock price” (as defined below under the caption “—Definitions”) of such make-whole fundamental change:

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If such make-whole fundamental change effective date or stock price is not set forth in the table above, then:

Notwithstanding anything to the contrary, in no event will the conversion rate be increased to an amount that exceeds 120.8459 shares of our common stock per $1,000 principal amount of notes, which amount is subject to adjustment in the same manner as, and at the same time and for the same events for which, the conversion rate is required to be adjusted pursuant to the provisions described above under the caption “—Conversion Rate Adjustments—Generally.”

For the avoidance of doubt, calling any notes for redemption will constitute a make-whole fundamental change only with respect to the notes called (or deemed called) for redemption, and not with respect to the notes not called for redemption. Accordingly, if we elect to redeem less than all of the outstanding notes, then holders of the notes not called for redemption will not be entitled to an increased conversion rate for such notes as described above on account of the redemption, except to the limited extent described above under the caption “—When the Notes May be Converted—Conversion upon Redemption.”

As set forth in the definition of “make-whole fundamental change conversion period” below under the caption “—Definitions,” if the conversion date for the conversion of a note occurs during a make-whole fundamental change conversion period relating to both a make-whole fundamental change resulting from our calling notes for redemption and another make-whole fundamental change, then, solely for purposes of that conversion, such conversion date will be deemed to occur only during the period relating to the make-whole fundamental change with the earlier make-whole fundamental change effective date. In that circumstance, the make-whole fundamental change with the later make-whole fundamental change effective date will be deemed not to occur for purposes of such conversion.

Adjustment of Stock Prices and Number of Additional Shares

The stock prices in the first row (i.e., the column headers) of the table above will be adjusted at the same time and for the same events for which, the conversion rate is adjusted as a result of the operation of the provisions described above under the caption “—Conversion Rate Adjustments—Generally.” The adjusted stock prices will equal the stock prices immediately prior to such adjustment, multiplied by a fraction, the numerator of which is the conversion rate immediately prior to the adjustment giving rise to the share price adjustment and the denominator of which is the conversion rate as so adjusted. The numbers of additional shares in the table above will be adjusted in the same manner as, and at the same time and for the same events for which, the conversion rate is adjusted pursuant to the provisions described above under the caption “—Conversion Rate Adjustments—Generally.”

Notice of Make-Whole Fundamental Change

We will notify noteholders and the trustee of each make-whole fundamental change no later than the second business day after the effective date of such make-whole fundamental change (in the case of a make-whole

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fundamental change pursuant to clause (i) of the definition thereof) or in the manner described above under the caption “—Optional Redemption” (in the case of a make-whole fundamental change pursuant to clause (ii) of the definition thereof).

Enforceability

Our obligation to increase the conversion rate as described above in connection with a make-whole fundamental change could be considered a penalty, in which case its enforceability would be subject to general principles of reasonableness and equitable remedies.

Effect of Common Stock Change Event

Generally

If there occurs any:

and, as a result of which, our common stock is converted into, or is exchanged for, or represents solely the right to receive, other securities, cash or other property, or any combination of the foregoing (such an event, a “common stock change event,” and such other securities, cash or property, the “reference property,” and the amount and kind of reference property that a holder of one share of our common stock would be entitled to receive on account of such common stock change event (without giving effect to any arrangement not to issue or deliver a fractional portion of any security or other property), a “reference property unit”), then, notwithstanding anything to the contrary,

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If the reference property consists of more than a single type of consideration to be determined based in part upon any form of stockholder election, then the composition of the reference property unit will be deemed to be the weighted average of the types and amounts of consideration actually received, per share of our common stock, by the holders of our common stock. We will notify the noteholders of such weighted average as soon as practicable after such determination is made.

We will not become a party to any common stock change event unless its terms are consistent with the provisions described under this “—Effect of Common Stock Change Event” caption.

Execution of Supplemental Indenture

At or before the effective time of the common stock change event, we and the resulting, surviving or transferee person (if not us) of such common stock change event (the “successor person”) will execute and deliver to the trustee a supplemental indenture that gives effect to the provisions described above and that contains such other provisions as we reasonably determine are appropriate to preserve the economic interests of the noteholders. If such reference property includes, in whole or in part, any stock or other securities, then such supplemental indenture will, to the extent applicable, provide for subsequent adjustments to the conversion rate in a manner consistent with the provisions described above. In addition, if the reference property includes, in whole or part, shares of stock or other securities or assets (other than cash or cash equivalents) of a person other than the successor person, then such other person will also execute such supplemental indenture and such supplemental indenture will contain such additional provisions we reasonably determine are appropriate to preserve the economic interests of noteholders.

Notice of Common Stock Change Event

No later than the second business day after the effective date of each common stock change event, we will notify the noteholders and the trustee of such common stock change event, including a brief description of the event, its effective date and a brief description of the anticipated change in the conversion right of the notes.

Equitable Adjustments to Prices

Whenever the indenture requires us to calculate the average of the last reported sale prices, or any function thereof, over a span of multiple days (including to calculate the stock price or an adjustment to the conversion rate), we will make proportionate adjustments to those calculations account for any adjustment to the conversion rate pursuant to paragraph (1) above under the caption “—Conversion Rights—Conversion Rate Adjustments—Generally” that becomes effective, or any event requiring such an adjustment to the conversion rate where the ex-dividend date or effective date, as applicable, of such event occurs, at any time during the period over which such average is to be calculated.

Exchange in Lieu of Conversion

When a noteholder surrenders any note for conversion, we may, at our election (an “exchange election”), direct the conversion agent to surrender, on or prior to the business day immediately following the conversion date, such note to one or more financial institutions designated by us for exchange in lieu of conversion. In order to accept any notes surrendered for conversion, the designated financial institution(s) must agree to timely pay or deliver, as the case may be, in exchange for such note, the consideration that would otherwise be due upon

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conversion as described above under “—Settlement upon Conversion.” To make an exchange election with respect to any note, we must, by the close of business on the business day following the relevant conversion date, notify in writing the trustee, the conversion agent (if other than the trustee) and the holder of such note and we must notify the designated financial institution(s) of the relevant deadline for delivery of the consideration due upon conversion and the type of conversion consideration to be paid or delivered, as the case may be.

Any notes exchanged by the designated financial institution(s) will remain outstanding, subject to the depositary procedures, if applicable. If any financial institution agrees to accept any notes for exchange but does not timely pay or deliver, as the case may be, the related conversion consideration, or if such designated financial institution does not accept the notes for exchange, then we will pay or deliver, as the case may be, the relevant conversion consideration, as, and at the time, required pursuant to the indenture as if we had not made the exchange election.

Our designation of any financial institution(s) to which the notes may be submitted for exchange does not require such financial institution(s) to accept any notes.

Fundamental Change Permits Noteholders to Require Us to Repurchase Notes

Generally

If a fundamental change occurs, then each noteholder will have the right (the “fundamental change repurchase right”) to require us to repurchase its notes (or any portion thereof in an authorized denomination) for cash on a date (the “fundamental change repurchase date”) of our choosing, which must be a business day that is no more than 35, nor less than 20, business days after the date we send the related fundamental change notice, as described below.

The repurchase price (the “fundamental change repurchase price”) for a note tendered for repurchase will be the principal amount of such note plus accrued and unpaid interest on such note to, but excluding, the fundamental change repurchase date. However, if the fundamental change repurchase date is after a regular record date and on or before the next interest payment date, then (i) the holder of such note at the close of business on such regular record date will be entitled, notwithstanding such repurchase, to receive, on or, at our election, before such interest payment date, the unpaid interest that would have accrued on such note to, but excluding, such interest payment date; and (ii) the fundamental change repurchase price will not include accrued and unpaid interest on such note to, but excluding, the fundamental change repurchase date.

Notwithstanding anything to the contrary above, we may not repurchase any notes if the principal amount of the notes has been accelerated and such acceleration has not been rescinded on or before the fundamental change repurchase date (except in the case of an acceleration resulting solely from a default by us in the payment of the related fundamental change repurchase price and any related interest described above on the fundamental change repurchase date).

Notice of Fundamental Change

On or before the 20th calendar day after the occurrence of a fundamental change, we will send to each noteholder and the trustee notice of such fundamental change containing certain information set forth in the indenture, including the fundamental change repurchase date, the fundamental change repurchase price and the procedures noteholders must follow to tender their notes for repurchase.

Procedures to Exercise the Fundamental Change Repurchase Right

To exercise its fundamental change repurchase right with respect to a note, the holder thereof must deliver a notice (a “fundamental change repurchase notice”) to the paying agent before the close of business on the business day immediately before the related fundamental change repurchase date (or such later time as may be required by law).

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The fundamental change repurchase notice must contain certain information set forth in the indenture, including the certificate number of any physical notes to be repurchased, or must otherwise comply with the depositary procedures in the case of a global note.

A noteholder that has delivered a fundamental change repurchase notice with respect to a note may withdraw that notice by delivering a withdrawal notice to the paying agent at any time before the close of business on the business day immediately before the fundamental change repurchase date. The withdrawal notice must contain certain information set forth in the indenture, including the certificate number of any physical notes with respect to which the withdrawal notice is being delivered, or must otherwise comply with the depositary procedures in the case of a global note.

Notes to be repurchased must be delivered to the paying agent (in the case of certificated notes) or the depositary procedures must be complied with (in the case of global notes) for the holder of those notes to be entitled to receive the fundamental change repurchase price.

Repurchase by Third Party

Notwithstanding anything to the contrary described above, we will be deemed to satisfy our obligations to repurchase notes pursuant to the provisions described above if (i) one or more third parties conduct the repurchase offer and repurchase tendered notes in a manner that would have satisfied our obligations to do the same if conducted directly by us; and (ii) an owner of a beneficial interest in the notes would not receive a lesser amount (as a result of taxes, additional expenses or for any other reason) than such owner would have received had we repurchased the notes.

No Repurchase Right in Certain Circumstances

Notwithstanding anything to the contrary, we will not be required to send a fundamental change notice, or offer to repurchase or repurchase any notes, as described above, in connection with a fundamental change occurring pursuant to clause (ii)(2) (or pursuant to clause (i) that also constitutes a fundamental change occurring pursuant to clause (ii)(2)) of the definition thereof, if:

We refer to any fundamental change with respect to which, in accordance with the provision described above, we do not offer to repurchase any notes as an “exempted fundamental change.”

Compliance with Securities Laws

We will comply in all material respects with all federal and state securities laws in connection with a repurchase following a fundamental change (including complying with the tender offer rules under the Exchange

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Act and filing any required Schedule TO, to the extent applicable) so as to permit effecting such repurchase in the manner described above. However, to the extent that the provisions of any securities laws or regulations adopted after the date on which the notes are first issued conflict with the provisions of the indenture relating to our obligations to purchase the notes upon a fundamental change, we will comply with such applicable securities laws and regulations and will not be deemed to have breached our obligations under such provisions of the indenture by virtue of such conflict.

Consolidation, Merger and Asset Sale

For purposes of the notes, the description below under this section titled “—Consolidation, Merger and Asset Sale” supersedes the information in the accompanying prospectus under the caption “Description of Debt Securities—Consolidation, Merger or Sale.”

We will not consolidate with or merge with or into, or (directly, or indirectly through one or more of our subsidiaries) sell, lease or otherwise transfer, in one transaction or a series of transactions, all or substantially all of the assets of us and our subsidiaries, taken as a whole, to another person (other than any such sale, lease or transfer to one or more of our “wholly owned subsidiaries” (as defined below under the caption “—Definitions”) not effected by means of a consolidation or merger) (a “business combination event”), unless:

At the effective time of a business combination event that complies with the provisions described above, the successor corporation (if not us) will succeed to, and may exercise every right and power of, us under the indenture and the notes, and, except in the case of a lease, the predecessor company will be discharged from its obligations under the indenture and the notes.

The definition of “business combination event” includes a reference to “all or substantially all” of our and our subsidiaries’ assets. There is no precise, established definition of the phrase “all or substantially all” under applicable law. Accordingly, there may be uncertainty as to whether the provisions described above would apply to a sale, lease or transfer of less than all of our and our subsidiaries’ assets.

Events of Default

For purposes of the notes, the description below under this section titled “—Events of Default” supersedes the information in the accompanying prospectus under the caption “Description of Debt Securities—Events of Default under the Indenture.”

Generally

An “event of default” means the occurrence of any of the following:

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