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                              AMENDED AND RESTATED
                          CERTIFICATE OF INCORPORATION
                                       OF
                                 SUPERGEN, INC.

         SuperGen, Inc., a corporation organized and existing under the laws of
the State of Delaware (the "Corporation"), certifies that:

         A.       The name of the Corporation is SuperGen, Inc. The original
                  Certificate of Incorporation was filed with the Secretary of
                  State of the State of Delaware on May 7, 1997.

         B.       This Amended and Restated Certificate of Incorporation was
                  duly adopted in accordance with the provisions of Sections 242
                  and 245 of the Delaware General Corporation Law by the Board
                  of Directors of the Corporation.

         C.       This Amended and Restated Certificate of Incorporation was
                  approved by the stockholders of the Corporation at a meeting
                  of the stockholders of the Corporation.

         D.       The Certificate of Incorporation of the Corporation is hereby
                  amended and restated in its entirety as follows:

FIRST:                     The name of the Corporation is SuperGen, Inc. (the
                           "Corporation").

SECOND:                    The address of the Corporation's registered office in
                           the State of Delaware is 1209 Orange Street, City of
                           Wilmington, County of New Castle, Delaware 19801. The
                           name of its registered agent at such address is The
                           Corporation Trust Company.

THIRD:                     The purpose of the Corporation is to engage in any
                           lawful act or activity for which corporations may be
                           organized under the General Corporation Law of
                           Delaware.

FOURTH:                    The Corporation is authorized to issue two classes of
                           stock to be designated respectively Common Stock and
                           Preferred Stock. The total number of shares of all
                           classes of stock which the Corporation has authority
                           to issue is 152,000,000, consisting of 150,000,000
                           shares of Common Stock, $0.001 par value (the "Common
                           Stock"), and 2,000,000 shares of Preferred Stock,
                           $0.001 par value (the "Preferred Stock").

                           The Preferred Stock may be issued from time to time
                           in one or more series. The Board of Directors is
                           hereby authorized subject to limitations prescribed
                           by law, to fix by resolution or resolutions the
                           designations, powers, preferences and rights, and the
                           qualifications, limitations or restrictions thereof,
                           of each such series of Preferred Stock, including
                           without limitation authority to fix by resolution or
                           resolutions, the dividend rights, dividend rate,

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                           conversion rights, voting rights, rights and terms of
                           redemption (including sinking fund provisions),
                           redemption price or prices, and liquidation
                           preferences of any wholly unissued series of
                           Preferred Stock, and the number of shares
                           constituting any such series and the designation
                           thereof, or any of the foregoing.

                           The Board of Directors is further authorized to
                           increase (but not above the total number of
                           authorized shares of the class) or decrease (but not
                           below the number of shares of any such series then
                           outstanding) the number of shares of any series, the
                           number of which was fixed by it, subsequent to the
                           issue of shares of such series then outstanding,
                           subject to the powers, preferences and rights, and
                           the qualifications, limitations and restrictions
                           thereof stated in the resolution of the Board of
                           Directors originally fixing the number of shares of
                           such series. If the number of shares of any series is
                           so decreased, then the shares constituting such
                           decrease shall resume the status which they had prior
                           to the adoption of the resolution originally fixing
                           the number of shares of such series.

FIFTH:                     The Corporation is to have perpetual existence.

SIXTH:                     The election of directors need not be by written
                           ballot unless a stockholder demands election by
                           written ballot at a meeting of stockholders and
                           before voting begins or unless the Bylaws of the
                           Corporation shall so provide.

SEVENTH:                   The number of directors which constitute the whole
                           Board of Directors of the Corporation shall be
                           designated in the Bylaws of the Corporation.

EIGHTH:                    In furtherance and not in limitation of the powers
                           conferred by the laws of the State of Delaware, the
                           Board of Directors is expressly authorized to adopt,
                           alter, amend or repeal the Bylaws of the Corporation.

NINTH:                     To the fullest extent permitted by the Delaware
                           General Corporation Law as the same exists or may
                           hereafter be amended, no director of the Corporation
                           shall be personally liable to the Corporation or its
                           stockholders for monetary damages for breach of
                           fiduciary duty as a director.

                           Neither any amendment nor repeal of this Article, nor
                           the adoption of any provision of this Certificate of
                           Incorporation inconsistent with this Article, shall
                           eliminate or reduce the effect of this Article in
                           respect of any matter occurring, or any cause of
                           action, suit or claim that, but for this Article,
                           would accrue or arise, prior to such amendment,
                           repeal or adoption of an inconsistent provision.

TENTH:                     At the election of directors of the Corporation, each
                           holder of stock of any class or series shall be
                           entitled to one vote for each share held. No
                           stockholder will be permitted to cumulate votes at
                           any election of directors.


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ELEVENTH:                  No action that is required or permitted to be taken
                           by the stockholders of the corporation at any annual
                           or special meeting of stockholders may be effected by
                           written consent of stockholders in lieu of a meeting
                           of stockholders.

TWELFTH:                   Meetings of stockholders may be held within or
                           without the State of Delaware, as the Bylaws may
                           provide. The books of the Corporation may be kept
                           (subject to any provision contained in the laws of
                           the State of Delaware) outside of 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
                           Bylaws of the Corporation.

THIRTEENTH:                The Corporation reserves the right to amend, alter,
                           change or repeal any provision contained in this
                           Certificate of Incorporation, in the manner now or
                           hereafter prescribed by the laws of the State of
                           Delaware, and all rights conferred herein are granted
                           subject to this reservation.

         IN WITNESS WHEREOF, SuperGen, Inc. has caused this Amended and Restated
Certificate of Incorporation to be signed by Joseph Rubinfeld, its President and
Chief Executive Officer, as of the date below.

Dated:  June 30, 2000

                                                  /S/ JOSEPH RUBINFELD
                                             -----------------------------------
                                             Joseph Rubinfeld


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