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                                                                   Exhibit 10.36

                                 PROMISSORY NOTE

South San Francisco, California                                          $82,600

July 12, 2002

     FOR VALUE RECEIVED, the undersigned David Morgans ("BORROWER") hereby
promises to pay to the order of Cytokinetics, Incorporated, a Delaware
corporation ("LENDER" also known as "Cytokinetics") at 280 East Grand Avenue,
South San Francisco, California (or at such other address as the holder of this
NOTE may designate by notice to BORROWER), in lawful money of the United States
of America, the sum of Eighty Two Thousand Six Hundred Dollars ($82,600), as set
forth below.

     1.     Definitions.

                  a.       "INTEREST RATE" shall mean the PRIME RATE plus 1%,
                           which sum is equal to 5.75% per annum.

                  b.       "SHARES" shall mean the options to purchase 137,666
                           shares of Common Stock of the LENDER presently held
                           by BORROWER and the shares of Common Stock of the
                           LENDER to be acquired by BORROWER upon exercise of
                           such options that will secure payment hereunder.

                  c.       "DUE DATE" shall mean the earliest of any of the
                           following:

                           (i)    the sale, conveyance, alienation, assignment,
                                  pledge, grant of any lien or other transfer by
                                  BORROWER of any of the SHARES without the
                                  prior written consent of the LENDER;

                           (ii)   ninety (90) days after TERMINATION OF
                                  EMPLOYMENT;

                           (iii)  eighteen (18) months after a LIQUIDITY EVENT;
                                  or

                           (iv)   such earlier date as may be required by LENDER
                                  upon acceleration of the DUE DATE in
                                  accordance with Section 5 of this NOTE.

                  d.       "TERMINATION OF EMPLOYMENT" shall mean the voluntary
                           or involuntary termination of BORROWER's employment
                           relationship with LENDER for any reason or no reason,
                           with or without cause.

                  e.       "LIQUIDITY EVENT" shall mean (i) an acquisition of
                           the LENDER in which the stockholders of the LENDER
                           receive cash or publicly traded securities in
                           exchange for their shares of stock of the LENDER, or
                           (ii) the

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                           first public offering by the LENDER of shares of its
                           capital stock pursuant to a registration statement on
                           Form S-1 under the Securities Act of 1933.

                  f.       "PRIME RATE" shall mean an interest rate equal to the
                           interest rate announced by the Federal Reserve Bank
                           of San Francisco as its prime rate as of the date of
                           this NOTE.

     2.     Payments.

                  a.       Commencing on the date hereof, interest on the unpaid
                           principal balance of this NOTE shall accrue at the
                           INTEREST RATE.

                  b.       The NOTE shall be repayable according to the
                           following schedule:

                           (i)    On the first anniversary of this NOTE, all
                                  interest accrued under this NOTE to such date;

                           (ii)   On the second anniversary of this NOTE, all
                                  interest accrued under this NOTE to such date;

                           (iii)  20% of the original principal balance of this
                                  NOTE on the third anniversary of this NOTE,
                                  plus all interest accrued under this NOTE to
                                  such date;

                           (iv)   20% of the original principal balance of this
                                  NOTE on the fourth anniversary of this NOTE,
                                  plus all interest accrued under this NOTE to
                                  such date;

                           (v)    20% of the original principal balance of this
                                  NOTE on the fifth anniversary of this NOTE,
                                  plus all interest accrued under this NOTE to
                                  such date; and

                           (vi)   40% of the original principal balance of this
                                  NOTE on the sixth anniversary of this NOTE,
                                  plus all interest accrued under this NOTE to
                                  such date.

                           Notwithstanding the foregoing, all principal and
                           accrued interest on the principal balance of this
                           NOTE shall be due and payable on the DUE DATE.

                  g.       All payments shall be applied first against accrued
                           interest, and secondly against principal.

     3.     Prepayment.

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         BORROWER may prepay all or any portion of the principal on this NOTE
         and the accrued interest without penalty or acceleration of the DUE
         DATE of this NOTE.

     4.     Security/Insurance.

         This NOTE is secured by a pledge of the SHARES under the terms of a
         SECURITY AGREEMENT, substantially in the form attached hereto as
         Exhibit A (the "SECURITY AGREEMENT") and dated as of even date hereof,
         and is subject to all of the provisions thereof.

     5.     Acceleration of DUE DATE.

         The entire unpaid principal of this NOTE and accrued interest thereon
         shall at the election of the LENDER, become immediately due and payable
         upon the occurrence of any of the following, irrespective of the DUE
         DATE as otherwise defined in this NOTE:

                  a.       BORROWER fails to make any payment when the same is
                           due;

                  b.       BORROWER fails to perform or observe any of the
                           covenants or obligations of BORROWER set forth in
                           this NOTE or contained in the SECURITY AGREEMENT for
                           a period of ten (10) days after written notice
                           thereof from LENDER;

                  c.       A bankruptcy or insolvency proceeding is instituted
                           by or against BORROWER, or if a receiver is appointed
                           for the property of BORROWER; or

                  d.       BORROWER makes an assignment for the benefit of
                           creditors.

     6.     Collection Costs Borne by BORROWER.

         In the event of any failure on the part of BORROWER to make any payment
         when the same is due, LENDER shall be entitled to recover from BORROWER
         all costs of effecting collection of the same, including reasonable
         attorneys' fees. Unpaid principal and interest subject to collection
         shall bear interest at the maximum rate allowed under California law
         for nonexempt lenders.

     7.     Certification of BORROWER.

         So long as the NOTE shall remain outstanding, BORROWER shall not sell,
         assign, transfer, convey, pledge, or grant a lien against the SHARES.
         In the event of any involuntary (by act of law or otherwise) sale,
         conveyance, pledge, lien, alienation or other transfer by BORROWER of
         any of the SHARES, BORROWER shall immediately notify LENDER.

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         BORROWER also warrants that, upon the written request of LENDER,
         BORROWER shall deliver to LENDER a written confirmation that a sale,
         conveyance, pledge, lien, alienation or other transfer of the SHARES
         has not occurred.

     8.     Full Recourse.

         The holder of this NOTE shall have full recourse against the BORROWER,
         and shall not be required to proceed against the collateral securing
         the NOTE pursuant to the SECURITY AGREEMENT in the event of the
         occurrence of an event set forth in Section 5 of this NOTE.

     9.     No Right to Continued Employment.

         Nothing contained herein shall be construed to confer on BORROWER any
         right to continued employment with the LENDER.

     10.    Governing Law.

         This NOTE shall be governed by and construed in accordance with the
         internal laws of the State of California. BORROWER consents to personal
         jurisdiction in any court in San Mateo County, California.

     11.    Successors.

         This NOTE shall be binding upon and shall inure to the benefit of the
         parties hereto and their respective representatives, heirs,
         administrators, successors and assigns.

Effective as of the date set forth above.

BORROWER:

         /s/ David Morgans
__________________________________________

Name:         David Morgans Jr.
      _____________________________________

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ACCEPTED AND ACKNOWLEDGED:

LENDER:

CYTOKINETICS, INCORPORATED, a Delaware corporation

By: /s/ James Sabry
   -------------------------------------
Name:
      ----------------------------------
Title:
       ---------------------------------
By: /s/ Robert Blum
    ------------------------------------
Name: Robert I. Blum
      ----------------------------------
Title: SVP Corp Dev & Finance & CFO
       ---------------------------------
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