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                                                                  EXHIBIT 10.2.2

                                  IXSYS, INC.

                            2000 STOCK INCENTIVE PLAN

                             STOCK OPTION AGREEMENT

                    (WITH EXERCISE BEFORE VESTING PERMITTED)

        Ixsys, Inc., a Delaware corporation (the "Company"), hereby grants an
Option to purchase its Common Stock to the Optionee named below. The terms and
conditions of the Option are set forth in this Stock Option Agreement and in the
Company's 2000 Stock Incentive Plan (the "Plan").

I. GRANT INFORMATION

Date of Grant:                          ____________, 20__

Name of Optionee:
                                        ----------------------------------------
Optionee's Social Security Number:         -  -
                                        --- -- ----

Type of Option:                         Nonstatutory ("NSO")

Number of Shares of Common Stock Covered by the Option:
                                                       -------------------------
Exercise Price per Share:               $
                                         ------------

Vesting Start Date:                     ____________, 20__

Vesting Schedule: Subject to attached Terms and Conditions, the Option shall
vest in full the fifth (5th) anniversary of the Vesting Start Date.
Notwithstanding the preceding sentence one hundred percent (100%) of the
unvested Options shall vest upon: (i) a Change in Control, so long as a Change
in Control occurs within two (2) years of the Vesting Start Date and the
consideration paid in stock and/or cash reflects a total Company valuation
exceeding two hundred fifty million dollars ($250,000,000) or (ii) the Company's
initial public offering ("IPO"), so long as the Company's IPO occurs within two
(2) years of the Vesting Start Date and the total market capitalization of the
Company at any time within 180 days of the IPO exceeds two hundred fifty million
dollars ($250,000,000)."


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        By signing below, you agree to all of the terms and conditions described
        in this Stock Option Agreement, including the attached Terms and
        Conditions, Notice of Exercise and Plan.

Optionee:
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                                      (Signature)

Company:
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                                      (Signature)
Title:
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        THE SECURITIES REPRESENTED HEREBY HAVE NOT BEEN REGISTERED OR QUALIFIED
UNDER THE SECURITIES ACT OF 1933 OR THE SECURITIES LAWS OF ANY STATE, AND MAY BE
OFFERED AND SOLD ONLY IF REGISTERED AND QUALIFIED PURSUANT TO THE RELEVANT
PROVISIONS OF FEDERAL AND STATE SECURITIES LAWS OR IF THE COMPANY IS PROVIDED AN
OPINION OF COUNSEL SATISFACTORY TO THE COMPANY THAT REGISTRATION AND
QUALIFICATION UNDER FEDERAL AND STATE SECURITIES LAWS IS NOT REQUIRED.

                  STOCK OPTION AGREEMENT - TERMS AND CONDITIONS

                            2000 STOCK INCENTIVE PLAN

                                   IXSYS, INC.

                       (INCLUDES EARLY EXERCISE PROVISION)

II. TERMS AND CONDITIONS

        1. VESTING. Your Option vests during your Service on the dates specified
in the first page of this Stock Option Agreement. Vesting will cease if your
Service terminates for any reason.

        2. SERVICE; LEAVES OF ABSENCE. Your Service shall cease when you cease
to be actively employed by, or a consultant or adviser to, the Company (or any
subsidiary) as determined in the sole discretion of the Board. For purposes of
your Option, your Service does not terminate when you go on a bona fide leave of
absence, that was approved by the Company in writing, if the terms of the leave
provide for continued service crediting, or when continued service crediting is
required by applicable law. Your Service terminates in any event when the
approved leave ends, unless you immediately return to active work. The Company
determines which leaves count toward Service, and when your Service terminates
for all purposes under the Plan.

        3. TERM OF OPTION. Your Option expires on the day before the 10th
anniversary of the Date of Grant, and will expire earlier if your Service
terminates as follows:

                (a) REGULAR TERMINATION. If your Service terminates for any
        reason except death or Disability, then your Option will expire at the
        close of business at Company headquarters on the date three (3) months
        after your termination date. During that three-month period, you may
        exercise that portion of your Option that was vested on the date that
        your Service terminated.

                (b) CAUSE. If your Service terminates for Cause, your Option
        will expire immediately.

                For purposes of this Section, "Cause" means (i) continued
        failure to perform substantially your duties, which standard of duties
        shall be referenced to the standards set

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        by the Company at the date of this Agreement (other than as a result of
        sickness, accident or similar cause beyond your reasonable control)
        after receipt of a written warning and given thirty (30) days to
        improve, (ii) willful and material misconduct, which is demonstrably and
        materially injurious to the Company or any of its subsidiaries,
        including willful and material failure to perform your duties as an
        officer or Employee of the Company or any of its subsidiaries or a
        material breach of this Agreement, (iii) conviction of or plea of nolo
        contendere to a felony; (iv) conviction of an act of fraud against, or
        the misappropriation of property belonging to the Company or any of its
        subsidiaries, or any employee, customer, or supplier of the Company or
        any of its subsidiaries.

                (c) DEATH. If you die while in Service, then your Option will
        expire at the close of business at Company headquarters on the date six
        (6) months after the date of death. During that six-month period, your
        estate or heirs may exercise that portion of your Option that was vested
        on the date of death.

                (d) DISABILITY. If your Service terminates because of your
        Disability, then your Option will expire at the close of business at
        Company headquarters on the date six (6) months after your termination
        date. During that six-month period, you may exercise that portion of
        your Option that was vested on the date of your Disability.

                "Disability" means that you are unable to engage in any
        substantial gainful activity by reason of any medically determinable
        physical or mental impairment.

        4. EXERCISE OF OPTION.

                (a) LEGAL RESTRICTIONS. By signing this Agreement, you agree not
        to exercise this Option or sell any Common Stock acquired upon exercise
        of this Option at a time when applicable laws, regulations or Company or
        underwriter trading policies prohibit exercise or sale. In particular,
        the Company shall have the right to designate one or more periods of
        time, each of which shall not exceed 180 days in length, during which
        this Option shall not be exercisable if the Company determines (in its
        sole discretion) that such limitation on exercise could in any way
        facilitate a lessening of any restriction on transfer pursuant to the
        Securities Act or any state securities laws with respect to any issuance
        of securities by the Company, facilitate the registration or
        qualification of any securities by the Company under the Securities Act
        or any state securities laws, or facilitate the perfection of any
        exemption from the registration or qualification requirements of the
        Securities Act or any applicable state securities laws for the issuance
        or transfer of any securities. Such limitation on exercise shall not
        alter the vesting schedule set forth in this Agreement other than to
        limit the periods during which this Option shall be exercisable.

                If the sale of Common Stock under the Plan is not registered
        under the Securities Act of 1933, as amended (the "Securities Act"), but
        an exemption is available which requires an investment or other
        representation, you shall represent and agree at the time of exercise
        that the Common Stock being acquired upon exercise of this Option are
        being acquired for investment, and not with a view to the sale or
        distribution thereof, and shall

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        make such other representations as are deemed necessary or appropriate
        by the Company and its counsel.

                (b) METHOD OF EXERCISE. To exercise your Option, you must
        execute the Notice of Exercise and Common Stock Purchase Agreement,
        attached hereto as Exhibit A (and, if exercise is prior to vesting, you
        must also execute Joint Escrow Instructions and Assignment Separate from
        Certificate, attached hereto as Exhibits B and C, respectively). You
        must submit the(se) form(s), together with full payment, at the address
        given on the form(s). Your exercise will be effective when it is
        received by the Company. If someone else wants to exercise your Option
        after your death, that person must prove to the Company's satisfaction
        that he or she is entitled to do so.

                (c) FORM OF PAYMENT. When you submit Exhibit A, you must include
        payment of the aggregate Exercise Price for the Common Stock you are
        purchasing. Payment may be made in one (or a combination) of the
        following forms.

                - Your personal check, a cashier's check or a money order.

                - Shares of Common Stock which you have owned for six months and
                  which are surrendered to the Company. The value of such Common
                  Stock, determined as of the effective date of the Option
                  exercise, will be applied to the Exercise Price.

                - A full recourse promissory note.

                - To the extent that a public market for Common Stock exists as
                  determined by the Company, by delivery (on a form approved by
                  the Company) of an irrevocable direction to a securities
                  broker to sell Common Stock and to deliver all or part of the
                  sale proceeds to the Company in payment of the aggregate
                  Exercise Price.

                - Any other form of legal consideration approved by the Board.

                (d) WITHHOLDING TAXES. You will not be allowed to exercise your
        Option unless you make acceptable arrangements to pay any withholding or
        other taxes that may be due as a result of the Option exercise or the
        sale of Common Stock acquired upon exercise of your Option.

        5. EXERCISE OF OPTION BEFORE VESTING ("EARLY EXERCISE"). You may
exercise your Option before it is fully vested, and the vesting provisions set
forth herein will apply to the Common Stock you acquire by exercising your
Option. If you exercise this Option before vesting, you should consider making
an election under Section 83(b) of the Internal Revenue Code of 1986, as amended
(the "83(b) Election"), a form of which is attached as Exhibit E. Please see the
Tax Summary attached as Exhibit F. THE 83(b) ELECTION MUST BE FILED WITHIN
THIRTY (30) DAYS AFTER THE DATE YOU EXERCISE ALL OR ANY PORTION OF YOUR OPTION
IN WHICH YOU ARE NOT VESTED.

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        6. RESALE RESTRICTIONS/MARKET STAND-OFF. In connection with any
underwritten public offering by the Company of its equity securities pursuant to
an effective registration statement filed under the Securities Act, including
the Company's initial public offering, you shall not, directly or indirectly,
engage in any transaction prohibited by the underwriter, nor shall you sell,
make any short sale of, contract to sell, transfer the economic risk of
ownership in, loan, hypothecate, pledge, grant any Option for the purchase of,
or otherwise dispose or transfer for value or agree to engage in any of the
foregoing transactions with respect to any Common Stock without the prior
written consent of the Company or its underwriters, for such period of time
after the effective date of such registration statement as may be requested by
the Company or such underwriters. Such period of time shall not exceed one
hundred eighty (180) days and may be required by the underwriter as a market
condition of the offering. By signing this Agreement you agree to execute and
deliver such other agreements as may be reasonably requested by the Company or
the underwriter which are consistent with the foregoing or which are necessary
to give further effect thereto. To enforce the provisions of this paragraph, the
Company may impose stop-transfer instructions with respect to the Common Stock
until the end of the applicable stand-off period.

        7. RIGHT OF FIRST REFUSAL. If you propose to sell, pledge or otherwise
transfer to a third party any Common Stock acquired under this Stock Option
Agreement, or any interest in such Common Stock, the Company shall have the
"Right of First Refusal" with respect to all (and not less than all) of such
Common Stock. If you desire to transfer Common Stock acquired under this Stock
Option Agreement, you must give a written "Transfer Notice" to the Company
describing fully the proposed transfer, including the number of shares proposed
to be transferred, the proposed transfer price and the name and address of the
proposed transferee. The Transfer Notice shall be signed both by you and by the
proposed new transferee and must constitute a binding commitment of both parties
to the transfer of the Common Stock. The Company shall have the right to
purchase all, and not less than all, of the Common Stock on the terms of the
proposal described in the Transfer Notice (subject, however, to any change in
such terms permitted in the next paragraph) by delivery of a notice of exercise
of the Right of First Refusal within thirty (30) days after the date when the
Transfer Notice was received by the Company.

        If the Company fails to exercise its Right of First Refusal before or
within thirty (30) days after the date when it received the Transfer Notice, you
may, not later than ninety (90) days following receipt of the Transfer Notice by
the Company, conclude a transfer of the Common Stock subject to the Transfer
Notice on the terms and conditions described in the Transfer Notice. Any
proposed transfer on terms and conditions different from those described in the
Transfer Notice, as well as any subsequent proposed transfer by you, shall again
be subject to the Right of First Refusal and shall require compliance with the
procedure described in the paragraph above. If the Company exercises its Right
of First Refusal, the parties shall consummate the sale of the Common Stock on
the terms set forth in the Transfer Notice within sixty (60) days after the date
when the Company received the Transfer Notice (or within such longer period as
may have been specified in the Transfer Notice); provided, however, that if the
Transfer Notice provided that payment for the Common Stock was to be made in a
form other than lawful money paid at the time of transfer, the Company shall
have the Option of paying for the Common Stock with lawful money equal to the
present value of the consideration described in the Transfer Notice.

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        The Company's Right of First Refusal shall inure to the benefit of its
successors and assigns, shall be freely assignable in whole or in part and shall
be binding upon any transferee of the Common Stock.

        The Company's Right of First Refusal shall terminate if the Company's
common stock is listed on an established stock exchange or is quoted regularly
on the Nasdaq Stock Market.

        8. TRANSFER OF OPTION. Prior to your death, only you may exercise your
Option. You cannot transfer or assign your Option. For instance, you may not
sell your Option or use it as security for a loan. If you attempt to do any of
these things, your Option will immediately become invalid. You may, however,
dispose of your Option in your will. Regardless of any marital property
settlement agreement, the Company is not obligated to honor a notice of exercise
from your spouse or former spouse, nor is the Company obligated to recognize
such individual's interest in your Option in any other way.

        9. NO RETENTION RIGHTS. Your Option does not give you the right to be
retained by the Company (or any subsidiaries) in any capacity. The Company
reserves the right to terminate your Service at any time and for any reason.

        10. STOCKHOLDER RIGHTS. You, or your estate or heirs, have no rights as
a stockholder of the Company until a certificate for your Common Stock has been
issued. No adjustments are made for dividends or other rights if the applicable
record date occurs before your stock certificate is issued, except as described
in the Plan.

        11. ADJUSTMENTS TO COMMON STOCK. In the event of a stock split, a stock
dividend or a similar change in the Company's Common Stock, the number of shares
covered by your Option and the exercise price per share may be adjusted pursuant
to the Plan. Your Option shall be subject to the terms of the agreement of
merger, liquidation or reorganization in the event the Company is subject to
such corporate activity.

        12. LEGENDS. All certificates representing the Common Stock issued upon
exercise of your Option shall, where applicable, have endorsed thereon the
following legends:

        "THE SECURITIES REPRESENTED BY THIS CERTIFICATE MAY NOT BE SOLD,
        TRANSFERRED, ENCUMBERED OR IN ANY MANNER DISPOSED OF, EXCEPT IN
        COMPLIANCE WITH THE TERMS OF A WRITTEN AGREEMENT BETWEEN THE
        COMPANY AND THE INITIAL HOLDER HEREOF. SUCH AGREEMENT PROVIDES
        FOR CERTAIN TRANSFER RESTRICTIONS, INCLUDING RIGHTS OF FIRST
        REFUSAL UPON AN ATTEMPTED TRANSFER OF THE SECURITIES AND RIGHTS
        OF REPURCHASE. THE SECRETARY OF THE COMPANY WILL UPON WRITTEN
        REQUEST FURNISH A COPY OF SUCH AGREEMENT TO THE HOLDER HEREOF
        WITHOUT CHARGE."

        "THE SECURITIES REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN
        REGISTERED OR QUALIFIED UNDER THE SECURITIES ACT OF 1933, AS
        AMENDED, OR THE SECURITIES LAWS OF ANY STATE, AND MAY BE OFFERED
        AND SOLD ONLY IF REGISTERED AND QUALIFIED

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        PURSUANT TO THE RELEVANT PROVISIONS OF FEDERAL AND STATE
        SECURITIES LAWS OR IF THE COMPANY IS PROVIDED AN OPINION OF
        COUNSEL SATISFACTORY TO THE COMPANY THAT REGISTRATION AND
        QUALIFICATION UNDER FEDERAL AND STATE SECURITIES LAWS ARE NOT
        REQUIRED."

        13. APPLICABLE LAW. This Agreement will be interpreted and enforced
under the laws of the State of California.

        14. INCORPORATION OF PLAN BY REFERENCE. The text of the Plan is
incorporated in this Agreement by reference. Certain capitalized terms used in
this Agreement are defined in the Plan.

        This Agreement and the Plan constitute the entire understanding between
you and the Company regarding your Option. Any prior agreements, commitments or
negotiations concerning your Option are superseded.


BY SIGNING THE COVER SHEET OF THIS AGREEMENT, YOU AGREE TO ALL OF THE TERMS AND
CONDITIONS DESCRIBED ABOVE AND IN THE PLAN. YOU ALSO ACKNOWLEDGE THAT YOU HAVE
READ SECTION 11, "PURCHASER'S INVESTMENT REPRESENTATIONS" OF EXHIBIT A AND THAT
YOU CAN AND HEREBY DO MAKE THE SAME REPRESENTATIONS WITH RESPECT TO THE GRANT OF
THIS OPTION.