Washington, D.C. 20549


Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940
OMB Number: 3235-0104
Estimated average burden
hours per response: 0.5
1. Name and Address of Reporting Person*
Sheridan Gail A

(Last) (First) (Middle)


(City) (State) (Zip)
2. Date of Event Requiring Statement (Month/Day/Year)
3. Issuer Name and Ticker or Trading Symbol
4. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
Director 10% Owner
X Officer (give title below) Other (specify below)
VP, Human Resources
5. If Amendment, Date of Original Filed (Month/Day/Year)
6. Individual or Joint/Group Filing (Check Applicable Line)
X Form filed by One Reporting Person
Form filed by More than One Reporting Person
Table I - Non-Derivative Securities Beneficially Owned
1. Title of Security (Instr. 4) 2. Amount of Securities Beneficially Owned (Instr. 4) 3. Ownership Form: Direct (D) or Indirect (I) (Instr. 5) 4. Nature of Indirect Beneficial Ownership (Instr. 5)
Table II - Derivative Securities Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 4) 2. Date Exercisable and Expiration Date (Month/Day/Year) 3. Title and Amount of Securities Underlying Derivative Security (Instr. 4) 4. Conversion or Exercise Price of Derivative Security 5. Ownership Form: Direct (D) or Indirect (I) (Instr. 5) 6. Nature of Indirect Beneficial Ownership (Instr. 5)
Date Exercisable Expiration Date Title Amount or Number of Shares
Employee Stock Option (right to buy) 01/14/2004(1) 01/14/2014 Common Stock 45,000(2) 1 D
Explanation of Responses:
1. Option immediately exercisable upon Date of Grant.
2. Shares subject to the Option shall be released from the Company's Repurchase Option per the following vesting schedule: 1/48th after one month (February 6, 2004) and 1/48th per month thereafter.
/s/ James H. Sabry, by power of attorney 04/28/2004
/s/ Robert I. Blum, by power of attorney 04/28/2004
** Signature of Reporting Person Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 5 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.

                                POWER OF ATTORNEY

         The undersigned, as a Section 16 reporting person of Cytokinetics,
Incorporated (the "Company"), hereby constitutes and appoints James H. Sabry and
Robert I. Blum, and each of them, the undersigned's true and lawful
attorney-in-fact to:

         1.       complete and execute Forms 3, 4 and 5 and other forms and all
                  amendments thereto as such attorney-in-fact shall in his or
                  her discretion determine to be required or advisable pursuant
                  to Section 16 of the Securities Exchange Act of 1934 (as
                  amended) and the rules and regulations promulgated thereunder,
                  or any successor laws and regulations, as a consequence of the
                  undersigned's ownership, acquisition or disposition of
                  securities of the Company; and

         2.       do all acts necessary in order to file such forms with the
                  Securities and Exchange Commission, any securities exchange or
                  national association, the Company and such other person or
                  agency as the attorney-in-fact shall deem appropriate.

         The undersigned hereby ratifies and confirms all that said
attorneys-in-fact and agents shall do or cause to be done by virtue hereof. The
undersigned acknowledges that the foregoing attorneys-in-fact, in serving in
such capacity at the request of the undersigned, are not assuming, nor is the
Company assuming, any of the undersigned's responsibilities to comply with
Section 16 of the Securities Exchange Act of 1934 (as amended).

         This Power of Attorney shall remain in full force and effect until the
undersigned is no longer required to file Forms 3, 4, and 5 with respect to the
undersigned's holdings of and transactions in securities issued by the Company,
unless earlier revoked by the undersigned in a signed writing delivered to the
Company and the foregoing attorneys-in-fact.

         IN WITNESS WHEREOF, the undersigned has caused this Power of Attorney
to be executed as of this 23rd day of April, 2004.

                             Signature: /s/ Gail A. Sheridan

                             Print Name: Gail A. Sheridan