1
                                                                     EXHIBIT 3.1


                           CERTIFICATE OF AMENDMENT
                                      OF
                         CERTIFICATE OF INCORPORATION
                                      OF
                           OSI PHARMACEUTICALS, INC.

                     ----------------------------------------

                     Adopted in accordance with the provisions
                     of Section 242 of the General Corporation
                           Law of the State of Delaware

                     ----------------------------------------

    I, the Secretary of OSI PHARMACEUTICALS, INC., a corporation organized and
existing under the laws of the State of Delaware, do hereby certify as follows:

    FIRST: That paragraph (a) of Article IV of the Certificate of Incorporation
of said corporation has been amended in its entirety to read as follows:

                                  ARTICLE IV

                                 CAPITAL STOCK

            (a) Authorized Stock. The total number of shares of stock
            which the Corporation shall have authority to issue is
            205,000,000 shares, consisting of 200,000,000 shares of
            Common Stock, having a par value of $.01, and 5,000,000
            shares of Preferred Stock, having a par value of $.01.

    SECOND: That such amendment has been duly adopted in accordance with the
provisions of the General Corporation Law of the State of Delaware by the
affirmative vote of the holders of not less than a majority of the outstanding
stock entitled to vote thereon.

    IN WITNESS WHEREOF, I have signed this certificate this 6th day of August,
2001.

                                              OSI PHARMACEUTICALS, INC.



                                              By: /s/ Robert L. Van Nostrand
                                                  --------------------------
                                                  Robert L. Van Nostrand
                                                  Secretary
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                          CERTIFICATE OF DESIGNATION OF
                 SERIES SRP JUNIOR PARTICIPATING PREFERRED STOCK

                                       OF

                            OSI PHARMACEUTICALS, INC.

        OSI PHARMACEUTICALS, INC., a corporation organized and existing under
the General Corporation Law of the State of Delaware (the "GCL"),

        DOES HEREBY CERTIFY THAT:

        Pursuant to authority conferred upon the Board of Directors by the
Certificate of Incorporation of said corporation, and pursuant to the provisions
of Section 151 of the GCL, said Board of Directors duly adopted at a meeting
pursuant to Section 141 of the GCL, a resolution creating Sixty Thousand
(60,000) shares of Series SRP Junior Participating Preferred Stock, which
resolution is attached hereto as Exhibit "A".

        IN WITNESS WHEREOF, said OSI PHARMACEUTICALS, INC. has caused this
certificate to be signed by its Secretary, this 23rd day of June 1999.


                                            OSI PHARMACEUTICALS, INC.



                                            By:    /s/  ROBERT L. VAN NOSTRAND
                                                   ---------------------------
                                                   Robert L. Van Nostrand
                                                   Secretary




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                                   Exhibit "A"
                            OSI PHARMACEUTICALS, INC.

                        Resolutions of Board of Directors
                         To be Adopted on June 23, 1999


Authorization of Series SRP Preferred Stock

        RESOLVED, that pursuant to the authority vested in the Board of
        Directors of this Corporation by the Certificate of Incorporation, the
        Board of Directors does hereby provide for the issuance of a series of
        preferred stock, par value $.01 per share (the "Preferred Stock"), to be
        designated "Series SRP Junior Participating Preferred Stock"
        (hereinafter referred to as the "Series SRP Preferred Stock"), initially
        consisting of 60,000 shares, and to the extent that the designations,
        relative rights, preferreds, limitations and restrictions of the Series
        SRP Preferred Stock are not stated and expressed in the Certificate of
        Incorporation, does hereby fix and herein state and express such
        designations, relative rights, preferreds, limitations and restrictions
        thereof as follows (all terms used herein which are defined in the
        Certificate of Incorporation shall be deemed to have the meanings
        provided therein):

              Section 1.    Designation and Amount. The shares of such series
        shall be designated as "Series SRP Junior Participating Preferred
        Stock" and the number of shares constituting such series shall be
        60,000.

              Section 2.    Dividends and Distributions.


              (A)     Subject to the prior and superior rights of the holders
        of any shares of any series of Preferred Stock ranking prior and
        superior to the shares of Series SRP Preferred Stock with respect to
        dividends, the holders of shares of Series SRP Preferred Stock shall
        be entitled to receive, when and as declared by the Board of Directors
        out of funds legally available for the purpose, quarterly dividends
        payable in cash on March 15, June 15, September 15 and December 15 in
        each year (each such date being referred to herein as a "Quarterly
        Dividend Payment Date"), commencing on the first Quarterly Dividend
        Payment Date after the first issuance of a share or fraction of a
        share of Series SRP Preferred Stock, in an amount per share (rounded
        to the nearest cent) equal to the greater of (a) $.025 or (b) 1,000
        times the aggregate per share (rounded to nearest cent) amount of all
        cash dividends and 1,000 times the aggregate per share amount (payable
        in kind) of all non-cash dividends or other distributions, other than
        a dividend payable in shares of common stock (the "Common Stock") or a
        subdivision of the outstanding shares of Common Stock (by
        reclassification or otherwise), declared on the Common Stock since the
        immediately preceding Quarterly Dividend Payment Date, or, with
        respect to the first Quarterly Dividend Payment Date, since the first
        issuance of any share or fraction of a share of Series SRP Preferred
        Stock.


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           (B)     The Corporation shall declare a dividend or distribution on
the Series SRP Preferred Stock as provided in paragraph (A) above immediately
after it declares a dividend or distribution on the Common Stock (other than a
dividend payable in shares of Common Stock); provided that, in the event no
dividend or distribution shall have been declared on the Common Stock during the
period between any Quarterly Dividend Payment Date and the next subsequent
Quarterly Dividend Payment Date, a dividend of $.025 per share on the Series SRP
Preferred Stock shall nevertheless be payable on such subsequent Quarterly
Dividend Payment Date.

           (C)     Dividends shall begin to accrue and be cumulative on each
outstanding share of Series SRP Preferred Stock from the first Quarterly
Dividend Payment Date following the date of issue of such share unless such date
of issue is a date after the record date for the determination of holders of
shares of Series SRP Preferred Stock entitled to receive a quarterly dividend on
such Quarterly Dividend Payment Date, in which event such dividends shall begin
to accrue and be cumulative on such shares from the second Quarterly Dividend
Payment Date following the date of issue of such share. Accrued but unpaid
dividends shall not bear interest. Dividends paid on the shares of Series SRP
Preferred Stock in an amount less than the total amount of such dividends at the
time accrued and payable on such shares shall be allocated pro rata on a
share-by-share basis among all such shares at the time outstanding. The Board of
Directors may fix a record date for the determination of holders of shares of
Series SRP Preferred Stock entitled to receive payment of a dividend or
distribution declared thereon, which record date shall be no more than 30 days
prior to the date fixed for the payment thereof.

           Section 3.   Voting Rights.  The holders of shares of Series SRP
Preferred Stock shall have the following voting rights:

           (A)     Subject to the provision for adjustment hereinafter set
forth, each share of Series SRP Preferred Stock shall entitle the holder thereof
to 1,000 votes on all matters submitted to a vote of the stockholders of the
Corporation.

           (B)     Except as otherwise provided herein or by law, the holders of
shares of Series SRP Preferred Stock and the holders of shares of Common Stock
shall vote together as one class on all matters submitted to a vote of
stockholders of the Corporation.

           (C)     (i)    If at any time dividends on any Series SRP Preferred
Stock shall be in arrears in an amount equal to six (6) quarterly dividends
thereon, the occurrence of such contingency shall mark the beginning of a period
(a "Default Period") which shall extend until such time when all accrued and
unpaid dividends for all previous quarterly dividend periods and for the current
quarterly dividend period on all shares of Series SRP Preferred Stock then
outstanding shall have been declared and paid or set apart for payment. During
each Default Period, all holders of Preferred Stock (including holders



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of the Series SRP Preferred Stock) on which dividends are in arrears in an
amount equal to six (6) quarterly dividends thereon, voting as a class,
irrespective of series, shall have the right to elect two (2) directors.

                   (ii)   During any Default Period, such voting rights of the
holders of Series SRP Preferred Stock may be exercised initially at a special
meeting called pursuant to subparagraph (iii) of this Section 3(C) or at any
annual meeting of stockholders, and thereafter at annual meetings of
stockholders, provided that neither such voting rights nor the right of the
holders of any other series of Preferred Stock, if any, to increase the
authorized number of directors shall be exercised unless the holders of ten
percent (10%) in number of shares of Preferred Stock outstanding shall be
present in person or by proxy. The absence of a quorum of the holders of Common
Stock shall not affect the exercise by the holders of Preferred Stock of such
voting right. At any meeting at which the holders of Preferred Stock shall
exercise such voting right initially during an existing Default Period, they
shall have the right, voting as a class, to elect directors to fill such
vacancies, if any, in the Board of Directors as may then exist up to two (2)
directors or, if such right is exercised at an annual meeting, to elect two (2)
directors. If the number which may be so elected at any special meeting does not
amount to the required number, the holders of the Preferred Stock shall have the
right to make such increase in the number of directors as shall be necessary to
permit the election by them of the required number. After the holders of the
Preferred Stock shall have exercised their right to elect directors in any
Default Period and during the continuance of such period, the number of
directors shall not be increased or decreased except by vote of the holders of
Preferred Stock as herein provided or pursuant to the rights of any equity
securities ranking senior to or pari passu with the Series SRP Preferred Stock.

                   (iii)  During an existing Default Period, unless the
holders of Preferred Stock shall have previously exercised their right to elect
directors, the Board of Directors may order, or any stockholder or stockholders
owning in the aggregate not less than ten percent (10%) of the total number of
shares of Preferred Stock outstanding, irrespective of series, may request, the
calling of a special meeting of the holders of Preferred Stock, which meeting
shall thereupon be called by the President, a Vice President or the Secretary of
the Corporation. Notice of such meeting and of any annual meeting at which
holders of Preferred Stock are entitled to vote pursuant to this paragraph
(C)(iii) shall be given to each holder of record of Preferred Stock by mailing a
copy of such notice to such holder at such holder's last address as the same
appears on the books of the Corporation. Such meeting shall be called for a time
not earlier than 20 days and not later than 60 days after such order or request
or in default of the calling of such meeting within 60 days after such order or
request, such meeting may be called on similar notice by any stockholder or
stockholders owning in the aggregate not less than ten percent (10%) of the
total number of shares of Preferred Stock outstanding. Notwithstanding the
provisions of this paragraph (C)(iii), no such special meeting shall be called
during the period within 60 days immediately preceding the date fixed for the
next annual meeting of the stockholders.

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                   (iv)   In any Default Period, the holders of Common Stock,
and other classes of stock of the Corporation if applicable, shall continue to
be entitled to elect the whole number of directors until the holders of
Preferred Stock shall have exercised their right to elect two (2) directors
voting as a class, after the exercise of which right (x) the directors so
elected by the holders of Preferred Stock shall continue in office until their
successors shall have been elected by such holders or until the expiration of
the Default Period and (y) any vacancy in the Board of Directors may (except as
provided in paragraph (C)(ii) of this Section 3) be filled by vote of a majority
of the remaining directors theretofore elected by the holders of the class of
stock which elected the Director whose office shall have become vacant.
References in this paragraph (C) to directors elected by the holders of a
particular class of stock shall include directors elected by such directors to
fill vacancies as provided in clause (y) of the foregoing sentence.

                   (v)    Immediately upon the expiration of a Default Period,
(x) the right of the holders of Preferred Stock as a class to elect directors
shall cease, (y) the term of any directors elected by the holders of Preferred
Stock as a class shall terminate and (z) the number of directors shall be such
number as may be provided for in or fixed pursuant to the Certificate of
Incorporation or by-laws irrespective of any increase made pursuant to the
provisions of paragraph (C)(ii) of this Section 3 (such number being subject,
however, to change thereafter in any manner provided by law or in the
Certificate Incorporation or By-laws). Any vacancies in the Board of Directors
affected by the provisions of clauses (y) and (z) in the preceding sentence may
be filled by a majority of the remaining directors.

           (D)     Except as set forth herein, holders of Series SRP Preferred
Stock shall have no special voting rights and their consent shall not be
required (except to the extent they are entitled to vote with holders of Common
Stock as set forth herein) for taking any corporate action.

           Section 4.     Certain Restrictions.


           (A)     Whenever quarterly dividends or other dividends or
distributions payable on the Series SRP Preferred Stock as provided in Section 2
are in arrears, thereafter and until all accrued and unpaid dividends and
distributions, whether or not declared, on shares of Series SRP Preferred Stock
outstanding shall have been paid in full, the Corporation shall not

                   (i)    declare or pay dividends on, make any other
distributions on, or redeem or purchase or otherwise acquire for consideration
any shares of stock ranking junior (either as to dividends or upon liquidation,
dissolution or winding up) to the Series SRP Preferred Stock;

                   (ii)   declare or pay dividends on or make any other
distributions on any shares of stock ranking on a parity (either as to dividends
or upon liquidation, dissolution


   7

or winding up) with the Series SRP Preferred Stock, except dividends paid
ratably on the Series SRP Preferred Stock and all such parity stock on which
dividends are payable or in arrears in proportion to the total amounts to which
the holders of all such shares are then entitled;



                   (iii)  redeem or purchase or otherwise acquire for
consideration shares of any stock ranking on a parity (either as to dividends or
upon liquidation, dissolution or winding up) with the Series SRP Preferred
Stock, provided that the Corporation may at any time redeem, purchase or
otherwise acquire shares of any such parity stock in exchange for shares of any
stock of the Corporation ranking junior (either as to dividends or upon
dissolution, liquidation or winding up) to the Series SRP Preferred Stock; or

                   (iv)   purchase or otherwise acquire for consideration any
shares of Series SRP Preferred Stock or any shares of stock ranking on a parity
with the Series SRP Preferred Stock, except in accordance with a purchase offer
made in writing or by publication (as determined by the Board of Directors) to
all holders of such shares upon such terms as the Board of Directors, after
consideration of the respective annual dividend rates and other relative rights
and preferreds of the respective series and classes, shall determine in good
faith will result in fair and equitable treatment among the respective series or
classes.

           (B)     The Corporation shall not permit any subsidiary of the
Corporation to purchase or otherwise acquire for consideration any shares of
stock of the Corporation unless the Corporation could, under paragraph (A) of
this Section 4, purchase or otherwise acquire such shares at such time and in
such manner.

           Section 5.     Reacquired Shares. Any shares of Series SRP Preferred
Stock purchased or otherwise acquired by the Corporation in any manner
whatsoever shall be retired and cancelled promptly after the acquisition
thereof. All such shares shall upon their cancellation become authorized but
unissued shares of Preferred Stock and may be reissued as part of a new series
of Preferred Stock to be created by resolution or resolutions of the Board of
Directors, subject to the conditions on issuance set forth herein.

           Section 6.     Liquidation, Dissolution or Winding Up.

           (A)     Upon any liquidation (voluntary or otherwise), dissolution or
winding up of the Corporation, no distribution shall be made to the holders of
shares of stock ranking junior (either as to dividends or upon liquidation,
dissolution or winding up) of the Series SRP Preferred Stock unless, prior
thereto, the holders of

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shares of Series SRP Preferred Stock shall have received $.01 per share plus an
amount equal to accrued and unpaid dividends and distribution thereon, whether
or not declared, to the date of such payment (the "Series SRP Liquidation
Preferred"). Following the payment of the full amount of the Series SRP
Liquidation Preferred, no additional distributions shall be made to the holders
of shares of Series SRP Preferred Stock unless, prior thereto, the holders of
shares of Common Stock shall have received an amount per share (the "Common
Adjustment") equal to the quotient obtained by dividing (i) the Series SRP
Liquidation Preferred by (ii) 1,000 (such number in clause (ii), the "Adjustment
Number"). Following the payment of the full amount of the Series SRP Liquidation
Preferred and the Common Adjustment in respect of all outstanding shares of
Series SRP Preferred Stock and Common Stock, respectively, holders of Series SRP
Preferred Stock and holders of shares of Common Stock shall receive their
ratable and proportionate share of the remaining assets to be distributed in the
ratio of the Adjustment Number to 1 with respect to such Preferred Stock and
Common Stock, on a per share basis, respectively.

           (B)     In the event, however, that there are not sufficient assets
available to permit payment in full of the Series SRP Liquidation Preferred and
the liquidation preferreds of all other series of Preferred Stock, if any, which
rank on a parity with Series SRP Preferred Stock, then such remaining assets
shall be distributed ratably to the holders of such parity shares in proportion
to their respective liquidation preferreds.

           Section 7.     Consolidation, Merger, etc. In case the Corporation
shall enter into any consolidation, merger, combination or other transaction in
which the shares of Common Stock are exchanged for or changed into other stock
or securities, cash or other property, then in any such case the shares of
Series SRP Preferred Stock shall at the same time be similarly exchanged or
changed in an amount per share equal to 1,000 times the aggregate amount of
stock, securities, cash and other property (payable in kind) into which or for
which each share of Common Stock is changed or exchanged.

           Section 8.     No Redemption.  The shares of Series SRP Preferred
Stock shall not be redeemable.

           Section 9.     Ranking. The Series SRP Preferred Stock shall rank
junior to all other series of the Corporation's Preferred Stock as to the
payment of dividends and the distribution of assets, unless the terms of any
such series shall provide otherwise.

           Section 10.    Amendment. The Certificate of Incorporation of the
Corporation shall not be further amended in any manner which would materially
alter or change the powers, preferreds or special rights of the Series SRP
Preferred Stock so as to affect them adversely without the affirmative vote of
the holders of a majority or more of the outstanding shares of Series SRP
Preferred Stock, voting separately as a class.

           Section 11.    Fractional Shares. Series SRP Preferred Stock may be
issued in fractions of a share which shall entitle the holder, in proportion to
such holder's fractional shares, to exercise voting rights, receive dividends,
participate in distributions and to have the benefit of all other rights of
holders of Series SRP Preferred Stock.






   9


                            CERTIFICATE OF AMENDMENT
                                       OF
                          CERTIFICATE OF INCORPORATION
                                       OF
                            OSI PHARMACEUTICALS, INC.
                       ----------------------------------

                    Adopted in accordance with the provisions
                    of Section 242 of the General Corporation
                          Law of the State of Delaware
                        ---------------------------------

            We, the President and Secretary of OSI PHARMACEUTICALS, INC., a
corporation existing under the laws of the State of Delaware, do hereby certify
as follows:

            FIRST:  That Article IV of the Certificate of Incorporation of
said corporation has been amended in its entirety to read as follows:

                                   ARTICLE IV
                                  CAPITAL STOCK

            (a) Authorized Stock. The total number of shares of stock which the
Corporation shall have authority to issue is 55,000,000 shares, consisting of
50,000,000 shares of Common Stock, having a par value of $.01 per share, and
5,000,000 shares of Preferred Stock having a par value of $.01 per share.

            (b) Preferred Stock. The board of directors is authorized, subject
to limitations prescribed by law and the provisions of this Article IV, to
provide for the issuance of shares of Preferred Stock in series, and by filing a
certificate pursuant to the applicable law of the State of Delaware, to
establish from time to time the number of shares to be included in each such
series, and to fix the designation, powers, preferences and other special and
relative rights of the shares of each such series and the qualifications,
limitations or restrictions thereof.

            The authority of the board of directors with respect to each series
shall include, but not be limited to, determination of the following:

            i. the number of shares constituting that series and the distinctive
            designation of that series, which number may be increased and
            decreased (but not below the number of shares then outstanding) from
            time to time by action of the board of directors;
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            ii. the dividend rate, if any, on the shares of that series, whether
            dividends shall be cumulative, and, if so, from which date or dates,
            and the relative rights of priority, if any, of payment of dividends
            on shares of that series;

            iii. whether that series shall have voting rights in addition to the
            voting rights provided by law, and if so, the terms of such voting
            rights;

            iv. whether that series shall have conversion privileges, and if so,
            the terms and conditions of such conversion, including provision for
            adjustment of the conversion rate upon the occurrence of such events
            as the board of directors shall determine;

            v. whether the shares of that series shall be redeemable, and, if
            so, the terms and conditions of such redemption, including the date
            or dates upon or after which they shall be redeemable, and the
            amount per share payable in case of redemption, which amount may
            vary under different conditions and at different redemption dates;

            vi. whether that series shall have a sinking fund for the redemption
            or purchase of shares of that series, and, if so, the terms and
            amounts of such sinking fund; and

            vii. the rights of the shares of that series in the event of
            voluntary or involuntary liquidation, dissolution or winding up of
            the Corporation, and the relative rights of priority, if any, of
            payment of shares of that series; and any other relative rights,
            preferences and limitations of that series.

            SECOND: That Article VII of the Certificate of Incorporation of said
corporation has been amended in its entirety to read as follows:
   11
                                   ARTICLE VII

                          MEETINGS OF STOCKHOLDERS AND
                       MEETINGS AND CONSENTS OF DIRECTORS;
                   CORPORATION BOOKS; ELECTIONS OF DIRECTORS;
                                   AND NOTICES

      Meetings of holders of Capital Stock of the Corporation and of the board
of directors and of any committee thereof may be held outside the State of
Delaware if the by-laws so provide. Except as otherwise provided by law or by
this certificate of incorporation, all actions of stockholders shall be taken at
an annual or special meeting of stockholders of the Corporation. No stockholder
action may be taken without a meeting, without prior notice and without a vote.
Any action required or permitted to be taken at any meeting of the board of
directors or of any committee thereof may be taken without a meeting as provided
by statute if the by-laws of the Corporation so provide. The elections of
directors need not be by ballot unless the by-laws of the Corporation so
provide. Except as otherwise provided by law, the books of the Corporation may
be kept outside the State of Delaware at such place or places as may be
designated from time to time by the board of directors or in the by-laws of the
Corporation. Any notice permitted or required by this certificate of
incorporation shall be written, signed by the sender and mailed, postage
prepaid, in the United States by certified or registered mail.

            THIRD: That such amendments have been duly adopted in accordance
with the provisions of the General Corporation Law of the State of Delaware by
the affirmative vote of the holders of not less than a majority of the
outstanding stock entitled to vote thereon.

            IN WITNESS WHEREOF, we have signed this certificate this 12th day of
April, 1999.

                                        /s/ Colin Goddard
                                        ------------------------------
                                        Colin Goddard, Ph.D.
                                        President and Chief Executive Officer


ATTEST: /s/ Robert L. Van Nostrand
        ------------------------------
        Robert L. Van Nostrand
        Secretary
   12
                       CERTIFICATE OF OWNERSHIP AND MERGER

                                     MERGING

                            OSI Pharmaceuticals, Inc.

                                      INTO

                             Oncogene Science, Inc.

                     (Pursuant to Section 253 of the General
                          Corporation Law of Delaware)

      Oncogene Science, Inc., a Delaware corporation (the "Corporation"), does
hereby certify:

            FIRST:  That the Corporation is incorporated pursuant to the
General Corporation Law of the State of Delaware.

            SECOND:  That the Corporation owns all of the outstanding shares
of each class of the capital stock of OSI Pharmaceuticals, Inc., a Delaware
corporation.

            THIRD:  That the Corporation, by the following resolutions of its
Board of Directors, duly adopted at a meeting thereof held on June 11, 1997,
determined to merge OSI Pharmaceuticals, Inc. into itself on the conditions
set forth in such resolutions:

                        RESOLVED, that the Corporation authorizes the formation
                  of a subsidiary under the Delaware General Corporation Law to
                  be named OSI Pharmaceuticals, Inc. and to be wholly-owned by
                  the Corporation; and further

                        RESOLVED, that effective October 1, 1997, the subsidiary
                  shall be merged with and into the Corporation, with the
                  Corporation to be the surviving corporation, and, upon the
                  effective date of the merger, the name of the surviving
                  corporation shall be changed to OSI Pharmaceuticals, Inc.; and
                  further
   13
                        RESOLVED, that the officers of the Corporation be, and
                  they hereby are, authorized, empowered and directed to take
                  such actions as shall be necessary or appropriate to
                  effectuate the foregoing resolutions.

            FOURTH: That this certificate of ownership and merger shall not
become effective until 12:01 a.m. Eastern Time on October 1, 1997.

      IN WITNESS WHEREOF, Oncogene Science, Inc. has caused its corporate seal
to be affixed hereto and this certificate to be signed by Robert L. Van
Nostrand, its authorized officer, this 26th day of September, 1997.

[SEAL]                                  ONCOGENE SCIENCE, INC.


                                        By: /s/ Robert L. Van Nostrand
                                            -----------------------------
                                            Robert L. Van Nostrand
                                            Vice President and
                                            Chief Financial Officer
   14
                            CERTIFICATE OF AMENDMENT

                                       OF

                          CERTIFICATE OF INCORPORATION

                                       OF

                             ONCOGENE SCIENCE, INC.


            I, the President of Oncogene Science, Inc., a corporation organized
and existing under the laws of the State of Delaware (the "Corporation"), do
hereby certify that (i) Article Fourth of the Corporation's Certificate of
Incorporation has been amended in its entirety to read as set forth below, and
(ii) such amendment was duly adopted in accordance with the provisions of
Section 242 of the General Corporation Law of the State of Delaware.

            FOURTH. The total number of shares of stock that the Corporation
            shall have authority to issue is 50,000,000 shares of common stock,
            having a par value of $.01 per share, all of the same class.

            IN WITNESS WHEREOF, I have hereunto set my hand and seal as of the
31st day of March, 1993.


(Corporate Seal)

Attest:


/s/ Theresa R. Dragone                  /s/ Gary E. Frashier          (SEAL)
- ------------------------------          ------------------------------
Theresa R. Dragone                      Gary E. Frashier, President
Secretary
   15
                            CERTIFICATE OF AMENDMENT

                                       OF

                          CERTIFICATE OF INCORPORATION

                                       OF

                             ONCOGENE SCIENCE, INC.


                    Adopted in accordance with the provisions
                    of Section 242 of the General Corporation
                          Law of the State of Delaware


            We, the President and Secretary of ONCOGENE SCIENCE, INC., a
corporation existing under the laws of the State of Delaware, do hereby certify
as follows:

            FIRST: That Article IX of the Certificate of Incorporation of said
corporation has been amended in its entirety to read as follows:

                                   ARTICLE IX
                          INDEMNIFICATION AND INSURANCE

                  SECTION 1. Right to Indemnification. Each person who was or is
            made a party or is threatened to be made a party to or is involved
            in any threatened, pending or completed action, suit or proceeding,
            whether civil, criminal, administrative or investigative
            ("Proceeding"), by reason of the fact that he, or a person of whom
            he is the legal representative, is or was the director, officer,
            employee or agent of the Corporation or is or was serving at the
            request of the Corporation as a director, officer, employee or agent
            of another corporation or of a partnership, joint venture, trust or
            other enterprise, including service with respect to employee benefit
            plans, whether the basis of such Proceeding is alleged action in an
            official capacity as a director, officer, employee or agent or in
            any other capacity
   16
            while serving as a director, officer, employee or agent, shall be
            indemnified and held harmless by the Corporation to the fullest
            extent authorized by the Delaware General Corporation Law, as the
            same exists or may hereafter be amended (out, in the case of any
            such amendment, only to the extent that such amendment permits the
            Corporation to provide broader indemnification rights than said law
            permitted the Corporation to provide prior to such amendment),
            against all expenses, liability and loss (including attorneys' fees,
            judgments, fines, ERISA excise taxes or penalties and amounts paid
            or to be paid in settlement) reasonably incurred or suffered by such
            person in connection therewith; provided, however, that the
            Corporation shall indemnify any such person seeking indemnity in
            connection with a Proceeding (or part thereof) initiated by such
            person only if the proceeding (or part thereof) was authorized by
            the Board of Directors of the Corporation. The right to
            indemnification conferred in this Section 1 shall be a contract
            right and shall include the right to be paid by the Corporation
            expenses incurred in defending any such Proceeding in advance of its
            final disposition; provided, however, that if the Delaware General
            Corporation Law requires, the payment of such expenses incurred by a
            director or officer in his capacity as a director or officer (and
            not in any other capacity in which service was or is rendered by
            such person while a director or officer, including, without
            limitation, service to an employee benefit plan) in advance of the
            final disposition of such Proceeding, shall be made only upon
            delivery to the Corporation of an undertaking, by or on behalf of
            such director or officer, to repay all amounts so advanced if it
            should be determined ultimately that such director of officer is not
            entitled to be indemnified under this Section or otherwise.

                  SECTION 2. Non-Exclusivity of Rights. The rights conferred on
            any person by Section 1 shall not be exclusive of any other right
            which such person may have or hereafter acquire under any statute,
            provision of the Certificate of Incorporation, by-laws, agreement,
            vote of stockholders or disinterested directors, or otherwise.

                  SECTION 3. Limitation of Liability of Directors. A director of
            the Corporation shall not be personally liable to the Corporation or
            its stockholders for monetary damages for breach
   17
            of fiduciary duty as a director except for liability (i) for any
            breach of the director's duty of loyalty to the Corporation or its
            stockholders, (ii) for acts or omissions not in good faith or which
            involve intentional misconduct or a knowing violation of law, (iii)
            under Section 174 of the Delaware General Corporation Law, or (iv)
            for any transaction from which the director derived an improper
            personal benefit.

                  SECTION 4. Insurance. The Corporation may maintain insurance,
            at its expense, to protect itself and any such director, officer,
            employee or agent of the Corporation or another corporation,
            partnership, joint venture, trust or other enterprise against any
            such expense, liability or loss, whether or not the Corporation
            would have the power to indemnify such person against such expense,
            liability or loss under the Delaware General Corporation Law.

            SECOND: That such amendment has been duly adopted in accordance with
the provisions of the General Corporation Law of the State of Delaware by the
affirmative vote of the holders of not less than a majority of the outstanding
stock entitled to vote thereon.

            IN WITNESS WHEREOF, we have signed this certificate this 9th day of
April, 1987.

                                        /s/ Robert E. Ivy
                                        ------------------------------
                                        Robert E. Ivy, President


                            ATTEST:     /s/ Gary Takata
                                        ------------------------------
                                        Gary Takata, Secretary
   18
                            CERTIFICATE OF AMENDMENT

                                       OF

                          CERTIFICATE OF INCORPORATION

                                       OF

                             ONCOGENE SCIENCE, INC.


                    Adopted in accordance with the provisions
                    of Section 242 of the General Corporation
                          Law of the State of Delaware


            We, the President and Secretary of ONCOGENE SCIENCE, INC., a
corporation existing under the laws of the State of Delaware, do hereby certify
as follows:

            FIRST: That Article FOURTH of the Certificate of Incorporation of
said corporation has been amended in its entirety to read as follows:

                  "FOURTH. The total number of shares of stock which the
            Corporation shall have authority to issue is 20,000,000 shares of
            common stock, of the par value of $.01 per share, all of the same
            class."

            SECOND: That such amendment has been duly adopted in accordance with
the provisions of the General Corporation Law of the State of Delaware by the
written consent of the holders of not less than a majority of the outstanding
stock entitled to vote thereon and that written notice of the corporation action
has been given to those stockholders who have not consented in writing, all in
accordance with the provisions of Section 228 of the General Corporation Law.
   19
            IN WITNESS WHEREOF, we have signed this certificate this 18th day of
January, 1986.


                                        /s/ Robert E. Ivy
                                        ------------------------------
                                        Robert E. Ivy, President


                            ATTEST:     /s/ Gary  Takata
                                        ------------------------------
                                        Gary Takata, Secretary
   20
                            CERTIFICATE OF AMENDMENT

                                       OF

                          CERTIFICATE OF INCORPORATION

                                       OF

                             ONCOGENE SCIENCE, INC.


                            (a Delaware corporation)


                         Adopted in accordance with the
                        provisions of Section 241 of the
                         General Corporation Law of the
                                State of Delaware


            THE UNDERSIGNED, Steven Gelles, sole incorporator of ONCOGENE
SCIENCE, INC., does hereby certify:

            FIRST: That the Certificate of Incorporation of ONCOGENE SCIENCE,
INC. (the "Corporation") was filed in the office of the Secretary of State of
Delaware on March 6, 1983 and a certified copy thereof was recorded in the
office of the Recorder of Kent County, Delaware on March 16, 1983.

            SECOND: That the Corporation has not received payment for its stock.

            THIRD: That the Certificate of Incorporation of the Corporation is
amended as follows:

                  (i)   By striking out paragraph FIRST thereof as it now exists
                        and inserting in lieu thereof ARTICLE I, reading as
                        follows:

                                    ARTICLE I
                                      NAME

            The name of the corporation is ONCOGENE SCIENCE, INC.
   21
                  (ii)  By striking out paragraph SECOND thereof as it now
                        exists and inserting in lieu thereof ARTICLE II, reading
                        as follows:

                                   ARTICLE II

                     REGISTERED OFFICE AND REGISTERED AGENT

            The registered office of the Corporation in the State of Delaware is
located at 229 South State Street, City of Dover, County of Kent. The name and
the address of the registered agent of the Corporation in the State of Delaware
is The Prentice-Hall Corporation System, Inc., 229 South State Street, Dover,
Delaware.

                  (iii) By striking out paragraph THIRD thereof as it now exists
                        and inserting in lieu thereof ARTICLE III, reading as
                        follows:

                                   ARTICLE III

                          CORPORATE PURPOSES AND POWERS

            The nature of the business of the Corporation, or the objects or
purposes to be transacted, promoted or carried on by the Corporation are any and
all lawful acts or activities for which corporations may be organized under the
General Corporation Law of Delaware, including but not limited to research and
development, manufacture, production, purchase or acquisition, and sale,
licensing, leasing, or disposition of materials, supplies, substances, chemicals
or equipment used or useful in the field of biotechnology or in any other field
in which such materials, supplies, substances, chemicals or equipment may
profitably be used.

                  (iv)  By striking out paragraph FOURTH thereof as it now
                        exists and inserting in lieu thereof ARTICLE IV, reading
                        as follows:

                                   ARTICLE IV
                                  CAPITAL STOCK

            The amount of the total authorized capital stock of this Corporation
is One Hundred Thousand Dollars ($100,000) consisting of Ten Million
(10,000,000) common shares, with a par value of one cent ($.01) each.

                  (v)   By striking out paragraph FIFTH thereof as it now exists
                        and inserting in lieu thereof ARTICLE V, reading as
                        follows:
   22
                                    ARTICLE V
                                  INCORPORATOR

            The name and mailing address of the sole incorporator of the
Corporation is:

            Name              Address
            ----              -------

            Steven Gelles     122 East 42nd Street
                              Suite 606
                              New York, New York 10168

                  (vi)  By adding thereto additional ARTICLES VI - XI, reading
                        as follows:

                                   ARTICLE VI

                          POWERS OF BOARD OF DIRECTORS

            In addition to and not in limitation of the powers conferred by
statute, the board of directors of the Corporation expressly is authorized:

                  (a) To make, adopt, alter, amend or repeal the by-laws, except
      as otherwise expressly provided in any by-law adopted by the holders of
      Capital Stock of the Corporation entitled to vote thereon. Any by-law may
      be altered, amended or repealed by the holders of Capital Stock of the
      Corporation entitled to vote thereon at any annual meeting or at any
      special meeting called for that purpose;

                  (b) To authorize and cause to be executed mortgages, liens,
      and other security interests upon the real and personal property of the
      Corporation;

                  (c) To determine the use and disposition of any surplus and
      net profits of the Corporation including, without limitation by
      specification, the determination of the amount of working capital required
      by the Corporation, to set apart out of any of the funds of the
      Corporation, whether or not available for dividends, a reserve or reserves
      for any proper purpose and to abolish any such reserve in the manner in
      which it was created;

                  (d) To designate, by resolution passed by a majority of the
      members of the board of directors, one or more committees, each consisting
      of two or more directors of the Corporation which, to the extent provided
      in the resolution designating
   23
      the committee or provided in the by-laws of the Corporation, have and may
      exercise, subject to the provisions of the General Corporation Law of
      Delaware, all the powers and authority of the board of directors in the
      management of the business and affairs of the Corporation. Such committee
      or committees may authorize the seal of the Corporation to be affixed to
      all papers which may require it. Such committee or committees shall have
      such name or names as may be provided in the by-laws of the Corporation or
      as may be determined from time to time by resolution adopted by the board
      of directors;

                  (e) To grant rights or options entitling the holders thereof
      to purchase from the Corporation shares of its Capital Stock evidenced by
      or in such instrument or instruments as shall be approved by the board of
      directors. The terms upon which, the time or times at or within which, the
      persons to whom, and the price or prices at which any such rights or
      options may be issued and any shares of Capital Stock may be purchased
      from the Corporation upon the exercise of any such right or option shall
      be such as shall be fixed in a resolution or resolutions adopted by the
      board of directors providing for the creation and issuance of such rights
      or options. In the absence of actual fraud in the transaction, the
      judgment of the board of directors as to the consideration for the
      issuance of such rights or options and the sufficiency thereof shall be
      conclusive. No such rights or options shall be invalidated or in any way
      affected by the fact that any director shall be a grantee thereof or shall
      vote for the issuance of such rights or options to himself or for any plan
      pursuant to which he may receive any such rights or options;

                  (f) To adopt such plans as from time to time may be approved
      by the board of directors for the purchase by officers or employees of the
      Corporation and of any corporation either affiliated with or a subsidiary
      of the Corporation of shares of Capital Stock of the Corporation. The
      terms upon which, the time or times at or within which and the price or
      prices at which shares of Capital Stock may be purchased from the
      Corporation pursuant to such plan shall be fixed in the plan by the board
      of directors. No such plan which is not at the time of adoption
      unreasonable or unfair shall be invalid or in any way affected because any
      director shall be entitled to purchase shares of Capital Stock of the
      Corporation thereunder and shall vote for such plan;

                  (g) To adopt or assume and carry out such plans as from time
      to time may be approved by the board of directors for the distribution
      among the officers or employees of the Corporation and of any corporation
      which is affiliated with or a subsidiary of the Corporation, or any of
      them, in addition to their regular salaries, of part of the earnings of
      the Corporation, in consideration for or in recognition of services
      rendered by such officers or employees or as an inducement to future
      efforts. No such
   24
      plan which is not at the time of adoption or assumption unreasonable or
      unfair shall be invalidated or in any way affected because any director
      shall be a beneficiary thereunder or shall vote for any plan under which
      he may benefit or for any distribution thereunder in which he may
      participate;

                  (h) To adopt such pension, profit sharing, retirement,
      deferred compensation or other employee benefit plans or provisions as
      may, from time to time, be approved by the board of directors, providing
      for pensions, profit sharing, retirement income, deferred compensation or
      other benefits for officers or employees of the Corporation and of any
      corporation which is affiliated with or a subsidiary of the Corporation,
      or any of them, in consideration for or in recognition of the services
      rendered by such officers or employees or as an inducement to future
      efforts. No such plan or provision, which is not at the time of adoption
      unreasonable or unfair shall be invalidated or in any way affected because
      any director shall be a beneficiary thereunder or shall vote for any plan
      or provision under which he may benefit; and

                  (i) To exercise, in addition to the powers and authorities
      herein or by law conferred upon the board of directors, any such powers
      and authorities and do all such acts and things as may be exercised or
      done by the Corporation subject, nevertheless, to the provisions of the
      General Corporation Law of Delaware, this certificate of incorporation and
      any by-laws from time to time adopted by the holders of Capital Stock of
      the Corporation entitled to vote thereon.

                                   ARTICLE VII

              MEETINGS AND CONSENTS OF STOCKHOLDERS AND DIRECTORS;
                   CORPORATION BOOKS; ELECTIONS OF DIRECTORS;
                                   AND NOTICES

            Meetings of holders of Capital Stock of the Corporation and of the
board of directors and of any committee thereof may be held outside the State of
Delaware if the by-laws so provide. Except as otherwise provided by law or by
this certificate of incorporation, any action required to be taken at any
annual, or special meeting of stockholders of the Corporation or any action
which may be taken at any annual or special meeting of such stockholders may be
taken without a meeting, without prior notice and without a vote, if a consent
in writing, setting forth the action so taken, shall be signed by the holders of
outstanding Capital Stock having not less than the minimum number of votes that
would be necessary to authorize or to take such action at a meeting at which all
shares of Capital Stock entitled to vote thereon were present and voted. Prompt
notice of the taking of the corporate action without a meeting by less than
unanimous written consent shall be given to those stockholders who have not
consented in writing. Any action required or permitted to be taken
   25
at any meeting of the board of directors or of any committee thereof may be
taken without a meeting as provided by statute if the by-laws of the Corporation
so provide. Except as otherwise provided by law, the books of the Corporation
may be kept outside the State of Delaware at such place or places as may be
designated from time to time by the board of directors or in the by-laws of the
Corporation. The elections of directors need not be by ballot unless the by-laws
of the Corporation so provide. Any notice permitted or required by this
certificate of incorporation shall be written, signed by the sender and mailed,
postage prepaid, in the United States by certified or registered mail.

                                  ARTICLE VIII

                    TRANSACTIONS WITH DIRECTORS AND OFFICERS

            No contract or transaction between the Corporation and one or more
of its directors or officers or between the Corporation and any other
corporation, partnership, association or other organization, in which one or
more of its directors or officers are directors or officers or have a financial
interest, shall be void or voidable solely for such reason or solely because the
director or officer is present at or participates in the meeting of the board of
directors or committee thereof which authorizes the contract or transaction or
solely because his or their votes are counted for such purpose if: (a) The
material facts as to his relationship or interest and as to the contract or
transaction are disclosed or are known to the board of directors or the
committee and the board of directors or the committee in good faith authorizes
the contract or transaction by the affirmative vote of a majority of the
disinterested directors even though the disinterested directors may be less than
a quorum; or (b) the material facts as to his relationship or interest and as to
the contract or transaction are disclosed or are known to the stockholders
entitled to vote thereon and the contract or transaction is specifically
approved in good faith by vote of the stockholders; or (c) the contract or
transaction is fair as to the Corporation as of the time it is authorized,
approved or ratified by the board of directors, a committee thereof or the
stockholders. Common or interested directors may be counted in determining the
presence of a quorum at a meeting of the stockholders or the board of directors
or of a committee which authorizes the contract or transaction.

                                   ARTICLE IX
                          INDEMNIFICATION AND INSURANCE

            SECTION 1. Indemnification by Corporation.

                  (a) Any person who was or is a party or is threatened to be
      made a party to any threatened, pending or completed action, suit or
      proceeding, whether civil, criminal, administrative or investigative
      (other than action by or in the right of the
   26
      Corporation) by reason of the fact that he is or was a director, officer,
      employee or agent of the Corporation or is or was serving at the request
      of the Corporation as a director, officer, employee or agent of another
      corporation, partnership, joint venture, trust or other enterprise, shall
      be indemnified by the Corporation, unless similar indemnification is
      provided by such other corporation or organization which may be involved
      (any funds received by any person as a result of the provisions of this
      Article shall be deemed an advance against his receipt of any such other
      indemnification from any such other corporation or organization), against
      expenses (including attorneys' fees), judgments, fines and amounts paid in
      settlement actually and reasonably incurred by such person in connection
      with such action, suit or proceeding if he acted in good faith and in a
      manner he reasonably believed to be in or not opposed to the best
      interests of the Corporation and, with respect to any criminal action or
      proceeding, had no reasonable cause to believe his conduct was unlawful.
      Any such person who could be indemnified pursuant to the preceding
      sentence except for the fact that the subject action or suit is or was by
      or in the right of the Corporation shall be indemnified by the Corporation
      against expenses (including attorneys' fees) actually and reasonably
      incurred by him, in connection with the defense or settlement of such
      action or suit except that no indemnification shall be made in respect of
      any claim, issue or matter as to which such person shall have been
      adjudged to be liable for negligence or misconduct in the performance of
      his duties to the Corporation unless and only to the extent that the Court
      of Chancery of the State of Delaware or the court in which such action or
      suit was brought shall determine upon application that, despite the
      adjudication of liability but in view of all the circumstances of the
      case, such person is fairly and reasonably entitled to indemnity for such
      expenses which the Court of Chancery or such other court shall deem
      proper;

                  (b) To the extent that a director, officer, employee or agent
      of the Corporation has been successful on the merits or otherwise in
      defense of any action, suit or proceeding referred to in paragraph (a) of
      this Section 1 or in defense of any claim, issue or matter therein, he
      shall be indemnified by the Corporation against expenses (including
      attorneys' fees) actually and reasonably incurred by him in connection
      therewith without the necessity of any action being taken by the
      Corporation other than the determination, in good faith, that such defense
      has been successful. In all other cases wherein indemnification is
      provided by this Article, unless ordered by a court, indemnification shall
      be made by the Corporation only as authorized in the specific case upon a
      determination that indemnification of the director, officer, employee or
      agent is proper in the circumstances because he has met the applicable
      standard of conduct specified in this Article. Such determination shall be
      made: (1) By the board of directors by a majority vote of a quorum
      consisting of directors who were not parties to such action, suit or
      proceeding; or (2) if such a quorum is not obtainable or, even if
      obtainable, a quorum of disinterested directors so directs, by independent
   27
      legal counsel in a written opinion; or (3) by the holders of a majority of
      the Capital Stock outstanding;

                  (c) The termination of any action, suit or proceeding by
      judgment, order, settlement, conviction or upon a plea of nolo contendere
      or its equivalent shall not create, of itself, a presumption that the
      person seeking indemnification did not act in good faith and in a manner
      which he reasonably believed to be in or not opposed to the best interests
      of the Corporation and, with respect to any criminal action or proceeding,
      had reasonable cause to believe that his conduct was unlawful. Entry of a
      judgment by consent as part of a settlement shall not be deemed final
      adjudication of liability for negligence or misconduct in the performance
      of duty or of any other issue or matter;

                  (d) Expenses incurred in defending a civil or criminal action,
      suit or proceeding may be paid by the Corporation in advance of the final
      disposition of such action, suit or proceeding as authorized by the board
      of directors in the specific case upon receipt of an undertaking by the
      director, officer, employee or agent involved to repay such amount unless
      it ultimately shall be determined that he is entitled to be indemnified by
      the Corporation; and

                  (e) The indemnification provided in this Article shall not be
      deemed exclusive of any other rights to which those seeking
      indemnification may be entitled under any by-law, agreement, vote of
      stockholders or disinterested directors or otherwise, both as to action in
      an official capacity and as to action in another capacity while holding
      such office, and shall continue as to a person who has ceased to be a
      director, officer, employee or agent and shall inure to the benefit of the
      heirs, executors and administrators of such person.

            SECTION 2. Insurance. By action of the board of directors,
notwithstanding any interest of the directors in the action, the Corporation may
purchase and maintain insurance, in such amounts as the board of directors deems
appropriate, on behalf of any person who is or was a director, officer, employee
or agent of the Corporation or is or was serving at the request of the
Corporation as a director, officer, employee or agent of another corporation,
partnership, joint venture, trust or other enterprise against any liability
asserted against him and incurred by him in any such capacity or arising out of
his status as such, whether or not the Corporation shall have the power to
indemnify him against such liability under the provisions of this Article.
   28
                                    ARTICLE X

                  COMPROMISE OR ARRANGEMENT BETWEEN CORPORATION
                        AND ITS CREDITORS OR STOCKHOLDERS

            Whenever a compromise or arrangement is proposed between this
Corporation and its creditors or any class of them and/or between this
Corporation and its stockholders or any class of them, any court of equitable
jurisdiction within the State of Delaware may, on the application in a summary
way of this Corporation or of any creditor or stockholder thereof or on the
application of any receiver or receivers appointed for this Corporation under
the provisions of Section 291 of Title 8 of the Delaware Code or on the
application of trustees in dissolution or of any receiver or receivers appointed
for this Corporation under the provisions of Section 279 of Title 8 of the
Delaware Code order a meeting of the creditors or class of creditors, and/or of
the stockholders or class of stockholders of this Corporation, as the case may
be, to be summoned in such manner as the said court directs. If a majority in
number representing three-fourths in value of the creditors or class of
creditors, and/or of the stockholders or class of stockholders of this
Corporation, as the case may be, agree to any compromise or arrangement and to
any reorganization of this Corporation as a consequence of such compromise or
arrangement, the said compromise or arrangement and the said reorganization
shall, if sanctioned by the court to which the said application has been made,
be binding on all the creditors or class of creditors, and/or on all the
stockholders or class of stockholders, of this Corporation, as the case may be,
and also on this Corporation.

                                   ARTICLE XI

                    RESERVATION OF RIGHT TO AMEND CERTIFICATE
                                OF INCORPORATION

            The Corporation reserves the right to amend, alter, change or repeal
any provisions contained in this certificate of incorporation in the manner now
or hereafter prescribed by law and by this certificate of incorporation. All the
provisions of this certificate of incorporation and all rights and powers
conferred in this certificate of incorporation on stockholders, directors and
officers are subject to such reserved power.

            FOURTH: That such amendment has been duly adopted in accordance with
the provision of Section 241 of the General Corporation Law of the State of
Delaware.
   29
            IN WITNESS WHEREOF, I have signed this certificate this 15th day of
April, 1983.


                                        /s/ Steven Gelles
                                        ------------------------------
                                        STEVEN GELLES
   30
                                   CERTIFICATE

                                       OF

                                  INCORPORATION

                                       OF

                             ONCOGENE SCIENCE, INC.

FIRST:      The name of this Corporation is ONCOGENE SCIENCE, INC.

SECOND:     Its Registered Office in the State of Delaware is to be located
            at 600 Bay Road, in the City of Dover, Zip Code 19901.  The
            Registered Agent in charge thereof is Ms. Pam Goldsborough.

THIRD:      The purpose of the Corporation is to perform research and to
            develop, manufacture, produce, purchase or otherwise acquire, and
            to sell, license, lease or otherwise dispose of materials,
            supplies, substances, chemicals or equipment used or useful in
            the field of Biotechnology or in any other field in which such
            materials, supplies, substances, chemicals or equipment may be
            profitably used and to engage in any lawful act or activity for
            which corporations may be organized under the General Corporation
            Law of Delaware.

FOURTH:     The amount of the total authorized capital stock of this Corporation
            is One Hundred Thousand Dollars ($100,000) divided into Ten Million
            (10,000,000) shares, of One Cent ($.01) each.

FIFTH:      The name and mailing address of the incorporator are as follows:

            Name:              Steven Gelles
            Mailing Address:   122 East 42nd Street, Suite 606
            Zip Code:          New York, New York 10168

I, THE UNDERSIGNED, for the purpose of forming a Corporation under the laws of
the State of Delaware, do make, file and record this Certificate, and do certify
that the facts herein stated are true, and I have accordingly hereto set my hand
this Tenth day of March, 1983.

                                        /s/ Steven Gelles
- ----------------------------            ------------------------------

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