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                                                                    EXHIBIT 10.5

                                 GENECRAFT, INC.

                             STOCK OPTION AGREEMENT

                   (INCENTIVE AND NONSTATUTORY STOCK OPTIONS)

     Pursuant to the Stock Option Grant Notice ("Grant Notice") and this Stock
Option Agreement, Genecraft, Inc. (the "Company") has granted you an option
under its 2002 Equity Incentive Plan (the "Plan") to purchase the number of
shares of the Company's Common Stock indicated in the Grant Notice at the
exercise price indicated in the Grant Notice. Defined terms not explicitly
defined in this Stock Option Agreement but defined in the Plan shall have the
same definitions as in the Plan.

     The details of your option are as follows:

     1. VESTING. Subject to the limitations contained herein, your option will
vest as provided in Section 6(f) of the Plan, provided that vesting will cease
immediately upon the termination of your Continuous Service for any reason.

     2. NUMBER OF SHARES AND EXERCISE PRICE. The number of shares subject to
your option and your exercise price per share referenced in the Grant Notice may
be adjusted from time to time for capitalization adjustments, as provided in
Section 11 of the Plan.

     3. METHOD OF PAYMENT. Payment of the exercise price is due in full upon
exercise of all or any part of your option. You may elect to make payment of the
exercise price in cash or by check or in any other manner expressly permitted by
the Plan.

     4. WHOLE SHARES. Your option may only be exercised for whole shares.

     5. SECURITIES LAW COMPLIANCE. Notwithstanding anything to the contrary
contained herein, your option may not be exercised unless the shares issuable
upon exercise of your option are then registered under the Securities Act or, if
such shares are not then so registered, the Company has determined that such
exercise and issuance would be exempt from the registration requirements of the
Securities Act. The exercise of your option must also comply with other
applicable laws and regulations governing the option, and the option may not be
exercised if the Company determines that the exercise would not be in material
compliance with such laws and regulations.

     6. TERM. Unless earlier terminated in accordance with the provisions of the
Plan, your option will terminate on the earliest to occur of:

          (A) the applicable date set forth in Section 6(g) of the Plan;

          (B) the Expiration Date indicated in the Grant Notice;

          (C) the occurrence of certain Corporate Transactions, as set forth in
Section 11 of the Plan.

GENECRAFT, INC.
STOCK OPTION AGREEMENT


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If your option is an incentive stock option, note that, to obtain the federal
income tax advantages associated with an "incentive stock option," the Code
requires that at all times beginning on the date of grant of the option and
ending on the day three (3) months before the date of the option's exercise, you
must be an employee of the Company or an Affiliate, except in the event of your
death or your Disability. The Company cannot in any circumstances guarantee that
your option will be treated as an "incentive stock option."

     7. EXERCISE.

          (A) You may exercise the vested portion of your option (and the
unvested portion of your option if the Grant Notice so permits) during its term
by delivering a Notice of Exercise (in a form designated by the Company)
together with the exercise price to the Secretary of the Company, or to such
other person as the Company may designate, during regular business hours,
together with such additional documents as the Company may then require.

          (B) By exercising your option you agree that, as a condition to any
exercise of your option, the Company may require you to enter an arrangement
providing for the payment by you to the Company of any tax withholding
obligation of the Company arising by reason of (1) the exercise of your option,
(2) the lapse of any substantial risk of forfeiture to which the shares are
subject at the time of exercise, and/or (3) the disposition of shares acquired
upon such exercise.

          (C) If your option is an incentive stock option, by exercising your
option you agree that you will notify the Company in writing within fifteen (15)
days after the date of any disposition of any of the shares of the Common Stock
issued upon exercise of your option that occurs within two (2) years after the
date of your option grant or within one (1) year after such shares of Common
Stock are transferred upon exercise of your option.

          (D) By exercising your option you agree that the Company (or a
representative of the underwriters) may, in connection with the first
underwritten registration of the offering of any securities of the Company under
the Securities Act, require that you not sell, dispose of, transfer, make any
short sale of, grant any option for the purchase of, or enter into any hedging
or similar transaction with the same economic effect as a sale, any shares of
Common Stock or other securities of the Company held by you, for a period of
time specified by the underwriter(s) (not to exceed one hundred eighty (180)
days) following the effective date of the registration statement of the Company
filed under the Securities Act. You further agree to execute and deliver such
other agreements as may be reasonably requested by the Company and/or the
underwriter(s) which are consistent with the foregoing or which are necessary to
give further effect thereto. In order to enforce the foregoing covenant, the
Company may impose stop-transfer instructions with respect to your Common Stock
until the end of such period.

          (E) By exercising your option you agree to execute and deliver to the
Company a Shareholders Agreement in substantially the form in use at the time of
exercise, unless you have previously executed and delivered such Shareholders
Agreement and it is in effect at the time you exercise your option.


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     8. RIGHT OF REPURCHASE; RIGHT OF FIRST REFUSAL. The Company will have
certain repurchase and first refusal rights with respect to shares you purchase
pursuant to your option, as set forth in Section 6(i) and Section 6(j) of the
Plan, respectively.

     9. TRANSFERABILITY. Your option is not transferable, except by will or by
the laws of descent and distribution, and is exercisable during your life only
by you. Notwithstanding the foregoing, by delivering written notice to the
Company, in a form satisfactory to the Company, you may designate a third party
who, in the event of your death, shall thereafter be entitled to exercise your
option.

     10. OPTION NOT A SERVICE CONTRACT. Your option is not an employment or
service contract, and nothing in your option shall be deemed to create in any
way whatsoever any obligation on your part to continue in the employ of the
Company or any Affiliate, or of the Company or any Affiliate to continue your
employment. In addition, nothing in your option shall obligate the Company or
any Affiliate, their respective stockholders, boards of directors, officers or
employees to continue any relationship that you might have as a director,
officer or consultant for the Company or any Affiliate.

     11. WITHHOLDING OBLIGATIONS.

          (A) At the time your option is exercised, in whole or in part, or at
any time thereafter as requested by the Company, you hereby authorize
withholding from payroll and any other amounts payable to you, and otherwise
agree to make adequate provision for (including by means of a "cashless
exercise" pursuant to a program developed under Regulation T as promulgated by
the Federal Reserve Board to the extent permitted by the Company), any sums
required to satisfy the federal, state, local and foreign tax withholding
obligations of the Company or an Affiliate, if any, which arise in connection
with your option.

          (B) Upon your request and subject to approval by the Company, in its
sole discretion, and compliance with any applicable conditions or restrictions
of law, the Company may withhold from fully vested shares of Common Stock
otherwise issuable to you upon the exercise of your option a number of whole
shares having a Fair Market Value, determined by the Company as of the date of
exercise, not in excess of the minimum amount of tax required to be withheld by
law. If the date of determination of any tax withholding obligation is deferred
to a date later than the date of exercise of your option, share withholding
pursuant to the preceding sentence shall not be permitted unless you make a
proper and timely election under Section 83(b) of the Code, covering the
aggregate number of shares of Common Stock acquired upon such exercise with
respect to which such determination is otherwise deferred, to accelerate the
determination of such tax withholding obligation to the date of exercise of your
option. Notwithstanding the filing of such election and subject to approval by
the Company in its sole discretion, shares shall be withheld solely from fully
vested shares of Common Stock determined as of the date of exercise of your
option that are otherwise issuable to you upon such exercise. Any adverse
consequences to you arising in connection with such share withholding procedure
shall be your sole responsibility.

          (C) Your option is not exercisable unless the tax withholding
obligations of the Company and/or any Affiliate are satisfied. Accordingly, you
may not be able to exercise


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your option when desired even though your option is vested, and the Company
shall have no obligation to issue a certificate for such shares or release such
shares from any escrow provided for herein.

     12. NOTICES. Any notices provided for in your option or the Plan shall be
given in writing and shall be deemed effectively given upon receipt or, in the
case of notices delivered by the Company to you, five (5) days after deposit in
the United States mail, postage prepaid, addressed to you at the last address
you provided to the Company.

     13. GOVERNING PLAN DOCUMENT. Your option is subject to all the provisions
of the Plan, the provisions of which are hereby made a part of your option, and
is further subject to all interpretations, amendments, rules and regulations
which may from time to time be promulgated and adopted pursuant to the Plan. In
the event of any conflict between the provisions of your option and those of the
Plan, the provisions of the Plan shall control.


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