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                                                                  EXHIBIT 3.1(2)

                           CERTIFICATE OF DESIGNATION
                           OF SERIES A PREFERRED STOCK
                              OF CERUS CORPORATION


        The undersigned, Stephen T. Isaacs, hereby certifies that:

        1. He is the duly elected and acting President and Secretary,
respectively, of CERUS CORPORATION, a Delaware corporation (the "Company"). The
date of filing of the Amended and Restated Certificate of Incorporation (the
"Certificate") was February 7, 1997.

        2. The Board of Directors of the Company adopted the following recitals
and resolutions as required by Section 151 of the General Company Law of the
State of Delaware at a meeting held on ______________, 1998:

                WHEREAS, the Certificate provides for a class of shares known as
        Preferred Stock, issuable from time to time in one or more series; and

                WHEREAS, the Board of Directors of the Company is authorized by
        Section A of Article IV of the Certificate and, pursuant to its
        authority as aforesaid, desires to fix the terms of the first series of
        said Preferred Stock, the number of shares constituting said series and
        the designation of said series.

                NOW, THEREFORE, BE IT RESOLVED, that the Board of Directors
        deems it advisable to adopt, and hereby adopts, the following
        Certificate of Designation of Preferences of Series A Preferred Stock of
        the Company:

               SECTION 1. DESIGNATION. Five Thousand (5,000) shares of Preferred
Stock, $0.001 par value, are designated "Series A Preferred Stock" with the
powers, preferences, rights, qualifications, limitations and restrictions
specified herein (the "Series A Preferred").

               SECTION 2. VOTING RIGHTS. The holders of shares of Series A
Preferred shall not have any voting rights, except as provided in this Section 2
and as required under the General Corporation Law of Delaware. Without first
obtaining the affirmative vote or written consent of the holders of at least a
majority of the outstanding shares of Series A Preferred, voting as a separate
class, the Company shall not effect any merger or consolidation in which the
Company is not the surviving entity, or any merger, consolidation or other
transaction in which the Company's Common Stock becomes no longer publicly
traded (a "Covered Transaction"), unless the surviving entity in the Covered
Transaction shall have provided for the benefit of the holders of Series A
Preferred contractual rights (the "Contractual Rights") to receive (i) on the
15th day following the Approval Payment Date (as hereinafter defined) or the
Termination Payment Date (as hereinafter defined), as the case may be, the
consideration that the holders of Series A Preferred would have received in the
Covered Transaction had the Series A Preferred been converted into Company
Common Stock immediately prior to the effectuation or consummation of the
Covered Transaction in accordance with the method of conversion used in Section
5(a)(1) or 5(a)(2), as the case may be, at one hundred twenty percent (120%) (in
the case of an Approval Event (as hereinafter defined)), or at one hundred
percent (100%) (in the case of 


                                       1.


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a Termination Event (as hereinafter defined)) of the closing price of the
Company's Common Stock immediately prior to the Covered Transaction, (with any
securities that would have been received as part of such consideration being
adjusted for any stock splits, stock combinations and the like from the date of
the Covered Transaction to the date of the Approval Event or the Termination
Event, as the case may be) and (ii) any dividends or other distributions, or
shares issued in any reclassification, exchange or substitution of securities or
in any reorganization, merger or consolidation, that the Series A Preferred
holders would have received from the date of the Covered Transaction to the date
of the Approval Event or Termination Event, as the case may be, in respect of
the securities, if any, that holders of the Series A Preferred would have
received in the Covered Transaction as set forth in (i) above; provided that the
Contractual Rights shall be subject to a right by the surviving entity to
repurchase, and upon a Termination Event, a right of the holders of a majority
of the outstanding shares of the Series A Preferred to require the repurchase
of, the Contractual Rights in the same manner, at the same times and at the same
price as the Company's right to redeem the Series A Preferred pursuant to
Section 4 below.

               SECTION 3. LIQUIDATION RIGHTS.

                      (a) Upon any liquidation, dissolution, or winding up of
the Company, whether voluntary or involuntary, the holders of Series A Preferred
shall be entitled to be paid out of the assets of the Company, before any
payment or distribution of assets of the Company (whether capital or surplus)
shall be made to or set aside for the holders of Common Stock and after and
subordinate to any other class or series of Preferred Stock, an amount per share
of Series A Preferred equal to the "Original Issue Price." The Original Issue
Price of the Series A Preferred shall be One Thousand Dollars ($1,000.00). If,
upon any liquidation, distribution, or winding up, the assets of the Company
shall be insufficient to make payment in full under this Section 3(a) to all
holders of Series A Preferred, then such assets shall be distributed among the
holders of Series A Preferred at the time outstanding, ratably in proportion to
the full stated amounts to which they would otherwise be respectively entitled
under this Section 3(a).

                      (b) The following events shall not be considered a
liquidation, dissolution or winding up under this Section 3:

                           (1) any consolidation or merger of the Company with
or into any other corporation or other entity or person, or any other corporate
reorganization or other transaction or series of transactions resulting in a
change in ownership of the outstanding securities of the Company; or

                           (2) a sale, lease or other disposition of all or any
part of the assets of the Company.

               SECTION 4. REDEMPTION.

                      (a) Upon (i) the approval of a new drug application (NDA)
or pre-market approval (PMA) or equivalent by the United States Food and Drug
Administration under the Development, Manufacturing and Marketing Agreement
dated as of December 10, 1993 between the Company and Baxter Healthcare
Corporation, as amended from time to time (the "Platelet Agreement") or (ii) CE
Mark approval in Europe under the Platelet Agreement (either, 


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an "Approval Event"), the Company shall have the right to redeem all or any
portion of the Series A Preferred at the Original Issue Price.

                      (b) Upon the termination for any reason of the Platelet
Agreement or upon cessation for any reason of the Cooperative Development Work
(as such term is defined in the Platelet Agreement) (either, a "Termination
Event"), the Company shall have the right, and the holders of a majority of the
outstanding shares of Series A Preferred shall have the right to require the
Company, to redeem all, but not less than all, the Series A Preferred at the
Original Issue Price.

                      (c) Immediately prior to consummation of a Covered
Transaction, the Company shall have the right to redeem all, but not less than
all, shares of Series A Preferred Stock then outstanding at the Original Issue
Price.

                      (d) In the event the Company desires to redeem the Series
A Preferred pursuant to Section 4(a), the Company shall, within ten (10) days
after the Approval Payment Date (as defined below), send a notice to the Series
A Preferred holders notifying the holders of redemption and setting forth the
number of shares of Series A Preferred to be redeemed and the total amount to be
paid for the shares of Series A Preferred being redeemed (the "Redemption
Price"). If, at the time of any redemption pursuant to Section 4(a) for less
than all of the Series A Preferred, there shall be more than one holder of the
Series A Preferred, such redemption shall be made pro rata among the holders of
the Series A Preferred in proportion to the number of shares of Series A
Preferred held by each such holder. The "Approval Payment Date" means the date
on which the Company receives payment of the amount payable to it under Section
4.3 of the Platelet Agreement

                      (e) In the event the Company or the holders of a majority
of the outstanding shares of the Series A Preferred desires to have the Series A
Preferred redeemed pursuant to Section 4(b) above, the Company or the Series A
Preferred holders shall, within ten (10) days after the Termination Payment Date
(as defined below), send a notice to the Company or the Series A Preferred
holders, as the case may be, stating that the Series A Preferred shall be
redeemed pursuant to this subsection (e). The amount to be paid for the Series A
Preferred being redeemed shall also be referred to as the "Redemption Price."
The "Termination Payment Date" means the date on which the Company receives
payment of the amount payable to it under Section 13.4 of the Platelet
Agreement.

                      (f) In the event the Company desires to have the Series A
Preferred redeemed pursuant to Section 4(c) above, the Company shall, not less
than ten (10) days before the date of consummation of the Covered Transaction,
send a notice to the Series A Preferred holders indicating that the Series A
Preferred shall be redeemed pursuant to this subsection (f). The amount to be
paid for the Series A Preferred being redeemed shall also be referred to as the
"Redemption Price."

                      (g) Within five (5) days after receipt of a redemption
notice from the Company or within five (5) days after the sending of a
redemption notice to the Company pursuant to Section 4(d), Section 4(e) or
Section 4(f) above, as the case may be, the Series A Preferred holders shall
surrender that number of Series A Preferred share certificates set forth in a
redemption notice by the Company, in the case of redemption pursuant to Section
4(a) above, 


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or all Series A Preferred share certificates, in the case of redemption pursuant
to Section 4(b) or Section 4(c) above, at the principal executive office of the
Company, and thereupon the Redemption Price shall be payable, in cash by wire
transfer or certified check, to the order of the person whose name appears on
such certificate or certificates as the owner thereof and each surrendered
certificate shall be canceled. Notwithstanding the foregoing, the Redemption
Price payable upon a redemption in connection with a Covered Transaction will be
payable, and the share certificates for the Series A Preferred shall be
canceled, only upon consummation of the Covered Transaction. If the Company does
not have sufficient funds legally available to redeem all shares to be redeemed
pursuant to this Section 4, then it shall use those funds which are legally
available to redeem the maximum possible number of such shares pro rata among
the holders of the Series A Preferred Stock. At any time thereafter when funds
of the Company are legally available for the redemption of shares of Series A
Preferred, such funds will immediately be used to redeem the balance of the
shares which the Company has become obligated to redeem pursuant to this Section
4 but which it has not redeemed. In the event that a redemption notice is given
pursuant to Section 4(f) above in connection with an impending Covered
Transaction, and the Covered Transaction is later terminated without being
consummated, the Company will so notify the holders of the Series A Preferred
Stock, and the redemption notice and redemption will be deemed rescinded and any
tendered share certificates will be returned to the holders of the Series A
Preferred, with the same effect as if such redemption notice had not been given.

               SECTION 5. CONVERSION RIGHTS. The following provisions shall
apply with respect to the conversion of the Series A Preferred into shares of
Common Stock:

                      (a) Conversion.

                           (1) Subject to Section 5(a)(3) below, upon the
occurrence of an Approval Event, if a notice of redemption of the Series A
Preferred has not been sent by the Company pursuant to Section 4(d) above, each
share of Series A Preferred shall automatically be converted into that number of
fully paid and nonassessable shares of Common Stock equal to the Original Issue
Price divided by one hundred twenty percent (120%) of the average closing price
of the Common Stock, as reported in The Wall Street Journal, for the thirty (30)
trading days prior to and including the trading day immediately prior to the
Approval Event. The date on which such conversion shall occur shall be the 15th
day following the Approval Payment Date.

                           (2) Subject to Section 5(a)(3) below, upon the
occurrence of a Termination Event, if a redemption notice has not been sent by
the Company or the holder of the Series A Preferred pursuant to Section 4(e)
above, each share of Series A Preferred shall automatically be converted into
that number of fully paid and nonassessable shares of Common Stock equal to the
Original Issue Price divided by the average closing price of the Common Stock,
as reported in The Wall Street Journal, for the thirty (30) trading days
commencing with the fifteenth (15th) trading day prior to the Termination Event.
The date on which such conversion shall occur shall be the 15th day following
the Termination Payment Date.

                           (3) Notwithstanding anything contained in this
Section 5 to the contrary, the Series A Preferred shall not convert, and no
shares of Common Stock shall be issued by the Company thereby, unless and until
the pre-merger notification requirements of the Hart-Scott-Rodino Antitrust
Improvements Act of 1976, as amended (the "HSR Act"), have been complied with,
and any waiting period under the HSR Act applicable to the conversion of the


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Series A Preferred has expired or been terminated and any approvals required
thereunder have been obtained.

                           (4) Upon the conversion of the Series A Preferred
pursuant to this Section 5, the outstanding shares of Series A Preferred shall
be converted automatically without any further action by the holders of such
shares and whether or not the certificates representing such shares are
surrendered to the Company or its transfer agent; provided, however, that the
Company shall not be obligated to issue certificates evidencing the shares of
Common Stock issuable upon such conversion unless the certificates evidencing
such shares of Series A Preferred are either delivered to the Company or its
transfer agent as provided below, or the holder notifies the Company or its
transfer agent that such certificates have been lost, stolen or destroyed and
executes an agreement satisfactory to the Company to indemnify the Company from
any loss incurred by it in connection with such certificates. Upon the
occurrence of such automatic conversion of the Series A Preferred, the holders
of Series A Preferred shall surrender the certificates representing such shares
at the office of the Company or any transfer agent for the Series A Preferred.
Thereupon, there shall be issued and delivered to such holder promptly at such
office and in its name as shown on such surrendered certificate or certificates,
a certificate or certificates for the number of shares of Common Stock into
which the shares of Series A Preferred surrendered were convertible on the date
on which such automatic conversion occurred.

                           (5) Notwithstanding anything contained in this
Section 5 to the contrary, in the event that the approval of the Company's
stockholders is required pursuant to Rule 4460(i) of the Nasdaq Stock Market
("Rule 4460(i)") prior to the issuance of any of the shares of Common Stock
issuable upon conversion of the Series A Preferred, the Company shall obtain
such approval by the applicable conversion date under Section 5(a)(i) or 5(a)(2)
hereof. In the event such approval is not obtained by the applicable conversion
date, the Company shall, in accordance with Section 4 hereof, redeem any shares
of Series A Preferred that would be convertible into shares of Common Stock in
excess of the limitation specified in Rule 4460(i).

                      (b) FRACTIONAL SHARES. No fractional shares of Common
Stock shall be issued upon conversion of Series A Preferred and the number of
shares of Common Stock to be issued shall be rounded down to the nearest whole
share. The Company shall, in lieu of issuing any fractional share, pay the
holder otherwise entitled to such fraction a sum in cash equal to the fair
market value of such fraction on the date of conversion (as determined in good
faith by the Board of Directors).

                      (c) RESERVATION OF STOCK ISSUABLE UPON CONVERSION. The
Company shall at all times reserve and keep available out of its authorized but
unissued shares of Common Stock or its treasury shares, solely for the purpose
of effecting the conversion of the shares of the Series A Preferred, such number
of its shares of Common Stock as shall from time to time be sufficient to effect
the conversion of all outstanding shares of the Series A Preferred. If at any
time the number of authorized but unissued shares of Common Stock shall not be
sufficient to effect the conversion of all then outstanding shares of the Series
A Preferred, the Company will take such corporate action as may, in the opinion
of its counsel, be necessary to increase its authorized but unissued shares of
Common Stock to such number of shares as shall be sufficient for such purpose.


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                      (d) NOTICES. Any notice required by the provisions of this
Section 5 to be given to the holders of shares of the Series A Preferred shall
be deemed given upon the earlier of actual receipt or seventy-two (72) hours
after the same has been deposited in the United States mail, by certified or
registered mail, return receipt requested, and addressed to each holder of
record at the address of such holder appearing on the books of the Company.

                      (e) PAYMENT OF TAXES. The Company will pay all taxes
(other than taxes based upon income) and other governmental charges that may be
imposed with respect to the issue or delivery of shares of Common Stock upon
conversion of shares of Series A Preferred, excluding any tax or other charge
imposed in connection with any transfer involved in the issue and delivery of
shares of Common Stock in a name other than that in which the shares of Series A
Preferred so converted were registered.


               SECTION 6. NOTICES OF RECORD. Upon any taking by the Company of a
record of the holders of any class of securities for the purpose of determining
the holders thereof who are entitled to receive any dividend or other
distribution, or upon any capital reorganization of the Company, any
reclassification or recapitalization of the capital stock of the Company, any
merger or consolidation of the Company with or into any other corporation, or
any transfer of all or substantially all the assets of the Company to any other
person, or any voluntary or involuntary dissolution, liquidation or winding up
of the Company, or any shareholders' meeting to approve the terms thereof, the
Company shall mail to each holder of Series A Preferred at least twenty (20)
days prior to the record date specified therein a notice specifying (i) the date
on which any such record is to be taken for the purpose of such dividend or
distribution and a description of such dividend or distribution, (ii) the date
on which any such reorganization, reclassification, transfer, consolidation,
merger, dissolution, liquidation or winding up is expected to become effective,
and the date of the shareholders meeting to approve the terms thereof, if
applicable, (iii) the date, if any, that is to be fixed as to when the holders
of record of Common Stock (or other securities) shall be entitled to exchange
their shares of Common Stock (or other securities) for securities or other
property deliverable upon such reorganization, reclassification, transfer,
consolidation, merger, dissolution, liquidation or winding up, and (iv) the
material terms thereof.

               SECTION 7. NO REISSUANCE OF PREFERRED STOCK. No share or shares
of Series A Preferred acquired by the Company by reason of redemption, purchase,
conversion or otherwise shall be reissued.

               SECTION 8. RESTRICTION ON TRANSFER. Neither the shares of Series
A Preferred nor any right to receive redemption payments, nor any Contractual
Rights, shall be assigned, transferred, hypothecated or otherwise alienated by
the holder thereof without the prior written consent of the Company, except (i)
in connection with, and to the transferee of, all or substantially all of the
business and assets of such holder, or (ii) to a direct or indirect wholly owned
subsidiary of Baxter International, Inc. Any such attempted action shall be null
and void. The foregoing restriction shall not apply to any Common Stock issued
on conversion of the Preferred Stock.

               SECTION 9. CANCELLATION OF PREFERRED STOCK. Upon the effectuation
or consummation of any Covered Transaction pursuant to which the holders of the
Series A Preferred receive the Contractual Rights, the Series A Preferred shall
be canceled.



                                       6.
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                RESOLVED FURTHER, that the President, the Chief Financial
        Officer or the Secretary be, and each of them hereby is, authorized to
        execute, verify and file, for and on behalf of the Company, the
        Certificate of Designation of Preferences with the Delaware Secretary of
        State in accordance with the General Company Law of the State of
        Delaware.

                RESOLVED FURTHER, that the officers of the Company be, and each
        of them hereby is, authorized and directed in the name and on behalf of
        the Company and under its corporate seal if appropriate, to execute and
        deliver all agreements and instruments, effect all filings and
        qualifications, and take all further action which is necessary or
        appropriate to carry out the foregoing resolutions.

        3. The authorized number of shares of Preferred Stock of this Company is
five million (5,000,000), none of which has been issued.


                           CERTIFICATE OF DESIGNATION
                               SERIES A PREFERRED


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IN WITNESS WHEREOF, this Company has caused this Certificate to be signed by its
duly authorized officer this _____ day of July, 1998.


                                    CERUS CORPORATION



                                    By:
                                       -------------------------------------
                                       Stephen T. Isaacs
                                       President


                           CERTIFICATE OF DESIGNATION
                               SERIES A PREFERRED