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                                                                 EXHIBIT 10.24.2

                    THIRD AMENDMENT TO EMPLOYMENT AGREEMENT

         This THIRD AMENDMENT TO EMPLOYMENT AGREEMENT (the "Amendment") is made
and entered into this 19th day of August, 2004, by and between EPOCH
BIOSCIENCES, INC., a Delaware corporation (the "Employer"), and William Gerber,
M.D., an individual (the "Employee").

                                    RECITALS:

         A. Employee and Employer are parties to that certain Second Amended and
Restated Employment Agreement dated as of January 10, 2002, as amended on
February 28, 2003 and April 2, 2004 (the "Employment Agreement"); and

         C. The parties desire to amend the Employment Agreement to correct and
clarify certain provisions relating to Employee's ability to terminate his
employment for "Good Reason" following a Change in Control of the Company.

                                   AGREEMENT:

         NOW, THEREFORE, in consideration of the foregoing premises and the
respective covenants and agreements of each party to the other set forth herein,
the parties hereto, intending to be legally bound, hereby agree as follows:

         1. Amendment to Section 4.1(f). The parties hereby amend, as of the
Effective Date of the Employment Agreement, Section 4.1(f) of the Employment
Agreement, such that Section 4.1(f) of the Employment Agreement shall read in
its entirety as follows:

                         "(f) For the purposes of this Agreement, "Good Reason"
            shall mean the assignment of Employee to a position within the
            Company, upon or within twelve (12) months following a Change in
            Control, which (i) is not equivalent in all material respects with
            the Employee's position with the Company prior to such Change in
            Control (taking into account the relative size of the Company prior
            to such Change in Control and the size of the acquiring entity, and
            other than actions that are not taken in bad faith and are remedied
            by the Company within five (5) business days after receipt of notice
            thereof from the Employee), (ii) requires the Employee to work at a
            location not within 50 miles of the Company's headquarters
            immediately prior to the Change in Control (the "Existing
            Location"), provided that Employee, if requested in writing by the
            Company, continues working at the Company at the Existing Location
            under the terms of this Agreement for a period of up to six (6)
            months following the Change in Control, or (iii) results in any
            reduction in the Employee's Base Salary. Notwithstanding the
            foregoing, in the event the Board of Directors reassigns Employee to
            another senior executive officer position with the Company, such
            reassignment shall not constitute "Good Reason" under clause (i) of
            this Section 4.1(f)."

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         2. Defined Terms. Unless otherwise defined herein, all capitalized
terms in this Amendment shall have the respective meanings ascribed to them in
the Employment Agreement.

         3. Effect on Employment Agreement. Except as specifically amended in
the manner and to the extent provided in Section 1 above, the Employment
Agreement shall remain unchanged and the Employment Agreement shall continue, as
and to the extent amended by this Amendment, in full force and effect.

         4. Conflicts. This Amendment shall be governed by all the terms and
conditions of the Employment Agreement. In the event of any conflict between the
terms of the Employment Agreement and the terms of this Amendment, the terms of
this Amendment will control.

         5. Counterpart Execution. This Amendment may be executed by facsimile
and in counterparts, each of which shall be deemed an original and all of which
when taken together shall constitute but one and the same instrument.

         IN WITNESS WHEREOF, the parties have executed this Third Amendment to
Employment Agreement as of the day and year set forth above.


                                               "EMPLOYER"

                                               EPOCH BIOSCIENCES, INC.,
                                               a Delaware corporation


                                               By: /s/ Fred Craves, Ph.D.
                                                   -----------------------------
                                                   Fred Craves, Ph.D.
                                                   Its: Chairman of the Board


                                               "EMPLOYEE"


                                               /s/ William G. Gerber, M.D.
                                               ---------------------------------
                                               William Gerber, M.D.




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