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                                                                    EXHIBIT 99.2

                                CERUS CORPORATION
                            NONSTATUTORY STOCK OPTION
                      (1998 NON-OFFICER STOCK OPTION PLAN)


_________________________, Optionee:

        CERUS CORPORATION (the "Company"), pursuant to its 1998 NON-OFFICER
STOCK OPTION PLAN (the "Plan"), has granted to you, the optionee named above, an
option to purchase shares of the common stock of the Company ("Common Stock").
This option is not intended to qualify as and will not be treated as an
"incentive stock option" within the meaning of Section 422 of the Internal
Revenue Code of 1986, as amended (the "Code").

        The details of your option are as follows:

        1. TOTAL NUMBER OF SHARES SUBJECT TO THIS OPTION. The total number of
shares of Common Stock subject to this option is ____________________ (______).

        2. VESTING. Subject to the limitations contained herein, your option
will vest according to the schedule indicated below (check one):

        [ ] 1/8th of the shares covered by the option will vest (become
exercisable) on ____________, 19__ (6 months after the date of grant) and 1/48th
of the shares will then vest each month thereafter.

        [ ] 1/48th of the shares covered by the option will vest (become
exercisable) each month after the date of grant.

In either case, the vesting of your option will continue until either (i) you
cease to provide services to the Company for any reason, or (ii) the option
becomes fully vested.

        3. EXERCISE PRICE AND METHOD OF PAYMENT.

        (a) EXERCISE PRICE. The exercise price of this option is
_______________________ ($____) per share, being not less than 85% of the fair
market value of the Common Stock on the date of grant of this option.

        (b) METHOD OF PAYMENT. Payment of the exercise price per share is due in
full upon exercise of all or any part of each installment that has accrued to
you. You may elect, to the extent permitted by applicable statutes and
regulations, to make payment of the exercise price under one of the following
alternatives:

               (i) Payment of the exercise price per share in cash (including
check) at the time of exercise;

               (ii) Payment pursuant to a program developed under Regulation T
as promulgated by the Federal Reserve Board which, prior to the issuance of
Common Stock, results in either the receipt of cash (or check) by the Company or
the receipt of irrevocable instructions to pay the aggregate exercise price to
the Company from the sales proceeds;


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               (iii) Provided that at the time of exercise the Company's Common
Stock is publicly traded and quoted regularly in the Wall Street Journal,
payment by delivery of already-owned shares of Common Stock, held for the period
required to avoid a charge to the Company's reported earnings, and owned free
and clear of any liens, claims, encumbrances or security interests, which Common
Stock shall be valued at its fair market value on the date of exercise; or

               (iv) Payment by a combination of the methods of payment permitted
by subsection 3(b)(i) through 3(b)( ii) above.

        4. WHOLE SHARES. This option may not be exercised for any number of
shares that would require the issuance of anything other than whole shares.

        5. SECURITIES LAW COMPLIANCE. Notwithstanding anything to the contrary
contained herein, this option may not be exercised unless the shares issuable
upon exercise of this option are then registered under the Securities Act of
1933, as amended (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.

        6. TERM. The term of this option commences on __________, 19__, the date
of grant, and expires at midnight on ______________________ (the "Expiration
Date," which is the day before the tenth anniversary from the date of grant),
unless this option expires sooner as set forth below or in the Plan. In no event
may this option be exercised on or after the Expiration Date. This option shall
terminate prior to the Expiration Date of its term as follows: three (3) months
after the termination of your Continuous Service (as defined in the Plan) with
the Company or an Affiliate of the Company unless one of the following
circumstances exists:

               (a) If your termination of Continuous Service is due to your
permanent and total Disability (as defined in the Plan), then this option will
then expire on the earlier of the Expiration Date set forth above or twelve (12)
months following such termination.

               (b) If your termination of Continuous Service is due to your
death or your death occurs within [three (3) months] following such termination,
then this option will then expire on the earlier of the Expiration Date set
forth above or eighteen (18) months after your death.

               (c) If during any part of such three (3) month period you may not
exercise your option solely because of the condition set forth in Section 5
above, then your option will not expire until the earlier of the Expiration Date
set forth above or until the expiration of a period of three (3) months after
your termination of Continuous Service during which exercise of the option would
not violate the condition set forth in Section 5 above.

               However, this option may be exercised following termination of
Continuous Service only as to that number of shares as to which it was
exercisable on the date of such termination under the schedule set forth in
Section 2 of this option.


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        7. Exercise.

               (a) This option may be exercised, to the extent specified above,
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 this option you agree that, as a precondition
to the completion of any exercise of this 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
this option; (2) the lapse of any substantial risk of forfeiture to which the
shares are subject at the time of exercise; or (3) the disposition of shares
acquired upon such exercise.

        8. TRANSFERABILITY. This 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 this
option.

        9. OPTION NOT A SERVICE CONTRACT. This option is not an employment
contract and nothing in this option shall be deemed to create in any way
whatsoever any obligation on your part to continue in the employ of the Company
or an Affiliate, or of the Company or an Affiliate to continue your employment.
In addition, nothing in this option shall obligate the Company or any Affiliate
of the Company, or their respective stockholders, Board of Directors, officers
or employees to continue any relationship that you might have as a Director or
Consultant for the Company or Affiliate.

        10. NOTICES. Any notices provided for in this 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 address
specified below or at such other address as you hereafter designate by written
notice to the Company.

        11. CHANGE OF CONTROL.

               (a) CHANGE IN CONTROL - ASSET SALE, MERGER, CONSOLIDATION OR
REVERSE MERGER. In the event of (1) a sale of substantially all of the assets of
the Company, (2) a merger or consolidation in which the Company is not the
surviving corporation or (3) a reverse merger in which the Company is the
surviving corporation but the shares of Common Stock outstanding immediately
preceding the merger are converted by virtue of the merger into other property,
whether in the form of securities, cash or otherwise, then any surviving
corporation or acquiring corporation (or a corporation which directly or
indirectly controls such corporation) shall assume any Options outstanding under
the Plan or shall substitute similar options (including an award to acquire the
same consideration paid to the stockholders in the transaction described in this
subsection 11(a)) for those outstanding under the Plan. In the event any
surviving corporation or acquiring corporation refuses to assume such Options or
to substitute similar options for those outstanding under the Plan, then with
respect to Options held by Participants whose Continuous


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Service has not terminated, the vesting of such Options (and, if applicable, the
time during which such Options may be exercised) shall be accelerated in full,
and the Options shall terminate if not exercised (if applicable) at or prior to
such event. With respect to any other Options outstanding under the Plan, such
Options shall terminate if not exercised (if applicable) prior to such event.

               (b) CHANGE IN CONTROL--DISSOLUTION OR LIQUIDATION. In the event
of a dissolution or liquidation of the Company, then all Options outstanding
under the plan shall be terminated if not exercised (if applicable) prior to
such event.

        12. GOVERNING PLAN DOCUMENT. This option is subject to all the
provisions of the Plan, a copy of which is attached hereto and its provisions
are hereby made a part of this option, including without limitation the
provisions of Section 7 of the Plan relating to option provisions and Section 11
relating to adjustments upon changes in stock, 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 this option and those of the Plan, the provisions of
the Plan shall control.

Dated the ____ day of _________, 19__.

                                          Very truly yours,

                                          CERUS CORPORATION



                                          By:
                                             -------------------------------
                                                 Duly authorized on behalf
                                                 of the Board of Directors

ATTACHMENTS:
        Cerus Corporation, Inc. 1998 Non-Officer Stock Option Plan
        Notice of Exercise


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                                           * * * *


        The undersigned:

        (a) Acknowledges receipt of the foregoing option and the attachments
referenced therein and understands that all rights and liabilities with respect
to this option are set forth in the option and the Plan; and

        (b) Acknowledges that as of the date of grant of this option, it sets
forth the entire understanding between the undersigned optionee and the Company
and its Affiliates regarding the acquisition of stock in the Company under this
option and supersedes all prior oral and written agreements on that subject with
the exception of (i) the options previously granted and delivered to the
undersigned under stock option plans of the Company, and (ii) the following
agreements only:

        NONE                        
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               (Initial)

        OTHER                                                    
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                                        OPTIONEE

                                        Address:
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