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                                                                   Exhibit 10.34

                                 PROMISSORY NOTE

         South San Francisco, California                            $37,400.00

         May 20, 2002

FOR VALUE RECEIVED, the undersigned David Morgans, ("EMPLOYEE") and Sandra
Morgans, (Collectively, "BORROWER") hereby promises to pay to the order of
Cytokinetics, Inc., 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
Thirty-Seven Thousand Four Hundred Dollars ($37,400.00), as set forth below.

1.       Definitions.

         a.       "CODE" shall mean the Internal Revenue Code of 1986, as
                  amended.

         b.       "APPLICABLE FEDERAL RATE" shall mean the monthly long-term
                  applicable Federal or other rate (as defined in the CODE) as
                  of the date of the occurrence of this NOTE.

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

                  (i)      thirty (30) days after TERMINATION OF EMPLOYMENT of
                           EMPLOYEE; or

                  (ii)     May 20, 2011, provided that if BORROWER is unable to
                           repay this NOTE at such time, LENDER in its
                           discretion shall consider extending the DUE DATE.

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

2.       Payments.

         a.       Interest on the unpaid principal balance of this NOTE shall
                  accrue at the APPLICABLE FEDERAL RATE, compounded monthly,
                  commencing on the date hereof.

         b.       No payment of principal or interest shall be due and payable
                  until the DUE DATE, at which time all accrued interest on the
                  principal balance of this NOTE shall be due and payable.

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

3.       Prepayment.

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

4.       Unsecured Note.

         This NOTE is unsecured.

5.       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.

         BORROWER warrants that BORROWER, shall immediately notify LENDER if any
         of the following occurs:

         a.       the sale, conveyance, alienation or other transfer by BORROWER
                  of the PRINCIPAL RESIDENCE, whether voluntary or involuntary,
                  by act of law or otherwise; or

         b.       any other change that removes BORROWER as a holder of record
                  of title to the PRINCIPAL RESIDENCE; or

         c.       any default under any deed of trust that is senior to the Deed
                  of Trust securing BORROWER'S obligation to LENDER hereunder.

         BORROWER also warrants that, upon the written request, of LENDER,
         BORROWER shall deliver to LENDER a written confirmation that none of
         the events listed immediately above has occurred. BORROWER further
         certifies that BORROWER reasonably expects to itemize deductions for
         each year during which this loan is outstanding.

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6.       Termination.

         The obligations of BORROWER hereunder shall terminate upon the
         indefeasible payment in full by BORROWER of all of its obligations
         evidenced by this NOTE.

7.       Forgiveness of NOTE and/or Accrued Interest.

         a.       In the event EMPLOYEE remains an employee in good standing of
                  LENDER, as determined in LENDER'S sole discretion, on the
                  fifth (5th) anniversary date of this NOTE, one quarter (1/4)
                  of the then outstanding principal balance of this NOTE shall
                  be forgiven on such date. Thereafter, in the event BORROWER
                  remains an employee in good standing of LENDER, as determined
                  in LENDER'S sole discretion, on each succeeding anniversary
                  date of this NOTE through and including the eighth (8th)
                  anniversary date hereof, one quarter (1/4) of the then
                  outstanding principal balance of this NOTE shall be forgiven
                  on each such date.

         b.       In the event EMPLOYEE remains an employee in good standing of
                  LENDER, as determined in LENDER'S sole discretion, on each
                  anniversary date of this NOTE, all accrued interest shall be
                  forgiven on such date.

         c.       In the event that EMPLOYEE dies or becomes permanently
                     disabled any outstanding principal balance of this NOTE and
                     all accrued interest shall be forgiven on such date.

         d.       In the event of any such forgiveness of principal and/or
                     interest, BORROWER shall be responsible for all taxes
                     related thereto.

8.       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.

9.       Successors.

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

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Effective as of the date set forth above.

BORROWER:

/s/ David Morgans
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David Morgans, Ph.D.

/s/ Sandra Morgans
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 Sandra Morgans

ACCEPTED AND ACKNOWLEDGED:

LENDER:

CYTOKINETICS, INC., a Delaware corporation

By: /s/ James Sabry
    ---------------------------------------
    James Sabry, Ph.D., M.D. President & CEO

 Name:
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 Title:
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