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                                                                 Exhibit 10.19.1


                              LIPID SCIENCES, INC.

                                 AMENDMENT NO. 1
                                       TO
                        INCENTIVE STOCK OPTION AGREEMENT

      This Amendment No. 1 (the "Amendment") to the Incentive Stock Option
Agreement dated as of ______________ (the "Option Agreement") between Lipid
Sciences, Inc., a Delaware corporation (the "Company") and the undersigned
optionee ("Participant") is entered into as of August 10, 2001.

         WHEREAS, the Company and Participant wish to provide for the
acceleration of vesting of Participant's option upon a Change of Control by
adding a definition of the "Change of Control." Capitalized terms used herein
without definition shall have the meanings given to them in the Option
Agreement.

      THE PARTIES AGREE AS FOLLOWS:

      1. Subsection 1(d) is hereby added to the Option Agreement, to read in its
entirety as follows:

                  (d) Change of Control. Notwithstanding the vesting schedule
                  set forth in Subsection 1(c), effective upon a Change of
                  Control (defined below), the vesting of each award shall
                  accelerate by the number of months such award has previously
                  vested. For purposes of this Subsection 1(d), a "Change of
                  Control" means:

                        (i) a reorganization, merger, share exchange or
                        consolidation of the Company with one or more other
                        corporations or other entities as a result of which the
                        holders of the shares outstanding immediately prior to
                        such transaction receive, as a group, less than 50% of
                        the voting power of the capital stock or other interests
                        of the surviving or resulting corporation or entity;

                        (ii) the sale of all or substantially all of the assets
                        of the Company; or

                        (iii) the liquidation or dissolution of the Company.

      2. Miscellaneous. Except as specifically set forth herein, the terms of
the Option Agreement shall remain unmodified and in full force and effect. This
Amendment shall be construed in accordance with and governed by the laws of the
State of California without regard to choice of law principles. The Company has
not provided the Participant



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with any tax advice regarding the Option Agreement or the Amendment and has
provided Participant with an opportunity to seek tax advice regarding the
Amendment.

         IN WITNESS WHEREOF, this Amendment has been executed by the parties
hereto as of the day and year first written above.

                                                     LIPID SCIENCES, INC.


                                                     By:________________________

                                                     Name:______________________

                                                     Title:_____________________




                                                     PARTICIPANT

                                                     ___________________________
                                                     Signature


                                                     ___________________________
                                                     Print Name



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