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                                                                  EXHIBIT 3.1(a)

                    RESTATED CERTIFICATE OF INCORPORATION OF

                           INTROGEN THERAPEUTICS, INC.

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         Introgen Therapeutics, Inc., a corporation organized and existing under
the laws of the State of Delaware (the "Corporation"), hereby certifies as
follows:

         A. The Corporation filed its original Certificate of Incorporation with
the Delaware Secretary of State under the name "Intron Therapeutics, Inc." on
June 17, 1993. The Corporation changed its name to "Introgen Therapeutics, Inc."
on August 22, 1994.

         B. This Restated Certificate of Incorporation was duly adopted by the
Corporation's directors and stockholders in accordance with the applicable
provisions of Sections 228, 242 and 245 of the Delaware General Corporation Law
(the "DGCL").

         C. This Restated Certificate of Incorporation restates, integrates and
amends the provisions of the Certificate of Incorporation of this Corporation,
as heretofore amended.

         D. The text of the Certificate of Incorporation, as heretofore amended,
is hereby amended and restated in its entirety to read as follows:

                                   ARTICLE I

         The name of this Corporation is Introgen Therapeutics, Inc.

                                   ARTICLE II

         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.

                                  ARTICLE III

         The purpose of the Corporation is to engage in any lawful act or
activity for which a corporation may be organized under the DGCL.

                                   ARTICLE IV

         The Corporation is authorized to issue two classes of shares of stock
to be designated, respectively, Common Stock, $0.001 par value, and Preferred
Stock, $0.001 par value. The total number of shares that the Corporation is
authorized to issue is 55,000,000 shares. The number of shares of Common Stock
authorized is 50,000,000. The number of shares of Preferred authorized is
5,000,000.

         The Preferred Stock may be issued from time to time in one or more
series pursuant to a resolution or resolutions providing for such issue duly
adopted by the Board of Directors (authority

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to do so being hereby expressly vested in the board). The Board of Directors is
further authorized to determine or alter the rights, preferences, privileges and
restrictions granted to or imposed upon any wholly unissued series of Preferred
Stock and to fix the number of shares of any series of Preferred Stock and the
designation of any such series of Preferred Stock. The Board of Directors,
within the limits and restrictions stated in any resolution or resolutions of
the Board of Directors originally fixing the number of shares constituting any
series, may increase or decrease (but not below the number of shares in any such
series then outstanding) the number of shares of any series subsequent to the
issue of shares of that series.

         The authority of the Board of Directors with respect to each such class
or series shall include, without limitation of the foregoing, the right to
determine and fix:

         (a) the distinctive designation of such class or series and the number
of shares to constitute such class or series;

         (b) the rate at which dividends on the shares of such class or series
shall be declared and paid, or set aside for payment, whether dividends at the
rate so determined shall be cumulative or accruing, and whether the shares of
such class or series shall be entitled to any participating or other dividends
in addition to dividends at the rate so determined, and if so, on what terms;

         (c) the right or obligation, if any, of the Corporation to redeem
shares of the particular class or series of Preferred Stock and, if redeemable,
the price, terms and manner of such redemption;

         (d) the special and relative rights and preferences, if any, and the
amount or amounts per share, which the shares of such class or series of
Preferred Stock shall be entitled to receive upon any voluntary or involuntary
liquidation, dissolution or winding up of the Corporation;

         (e) the terms and conditions, if any, upon which shares of such class
or series shall be convertible into, or exchangeable for, shares of capital
stock of any other class or series, including the price or prices or the rate or
rates of conversion or exchange and the terms of adjustment, if any;

         (f) the obligation, if any, of the Corporation to retire, redeem or
purchase shares of such class or series pursuant to a sinking fund or fund of a
similar nature or otherwise, and the terms and conditions of such obligation;

         (g) voting rights, if any, on the issuance of additional shares of such
class or series or any shares of any other class or series of Preferred Stock;

         (h) limitations, if any, on the issuance of additional shares of such
class or series or any shares of any other class or series of Preferred Stock;
and

         (i) such other preferences, powers, qualifications, special or relative
rights and privileges thereof as the Board of Directors of the Corporation,
acting in accordance with this

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Restated Certificate of Incorporation, may deem advisable and are not
inconsistent with law and the provisions of this Restated Certificate of
Incorporation.

                                   ARTICLE V

         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 statute, and all rights conferred upon the
stockholders herein are granted subject to this right.

                                   ARTICLE VI

         The Corporation is to have perpetual existence.

                                  ARTICLE VII

         1. Limitation of Liability. To the fullest extent permitted by the DGCL
as the same exists or as may hereafter be amended, a director of the Corporation
shall not be personally liable to the Corporation or its stockholders for
monetary damages for breach of fiduciary duty as a director.

         2. Indemnification. To the fullest extent permitted by applicable law,
this Corporation is authorized to provide indemnification of (and advancement of
expenses to) directors, officers, employees and other agents of this Corporation
(and any other persons to which Delaware law permits this Corporation to provide
indemnification), through Bylaw provisions, agreements with any such director,
officer, employee or other agent or other person, vote of stockholders or
disinterested directors, or otherwise, in excess of the indemnification and
advancement otherwise permitted by Section 145 of the DGCL.

         3. Amendments. Neither any amendment nor repeal of this Article VII,
nor the adoption of any provision of the Corporation's Certificate of
Incorporation inconsistent with this Article VII, shall eliminate or reduce the
effect of this Article VII, in respect of any matter occurring, or any action or
proceeding accruing or arising or that, but for this Article VII, would accrue
or arise, prior to such amendment, repeal, or adoption of an inconsistent
provision.

                                  ARTICLE VIII

         In the event any shares of Preferred Stock shall be redeemed or
converted pursuant to the terms hereof, the shares so converted or redeemed
shall not revert to the status of authorized but unissued shares, but instead
shall be canceled and shall not be re-issuable by the Corporation.

                                   ARTICLE IX

         Holders of stock of any class or series of the Corporation shall not be
entitled to cumulate their votes for the election of directors or any other
matter submitted to a vote of the stockholders.

         1. Number of Directors. The number of directors which constitutes the
whole Board of Directors of the Corporation shall be designated in the
Corporation's Bylaws. The directors shall be


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divided into three classes with the term of office of the first class (Class I)
to expire at the annual meeting of stockholders held in 2001; the term of office
of the second class (Class II) to expire at the annual meeting of stockholders
held in 2002; the term of office of the third class (Class III) to expire at the
annual meeting of stockholders held in 2003; and thereafter for each such term
to expire at each third succeeding annual meeting of stockholders after such
election.

         2.  Election of Directors.  Elections of directors need not be by
written ballot unless the Corporation's Bylaws shall so provide.

                                   ARTICLE X

         In furtherance and not in limitation of the powers conferred by
statute, the Board of Directors is expressly authorized to make, alter, amend or
repeal the Corporation's Bylaws.

                                   ARTICLE XI

         No action shall be taken by the stockholders of the Corporation except
at an annual or special meeting of the stockholders called in accordance with
the Corporation's Bylaws and no action shall be taken by the stockholders by
written consent. The affirmative vote of at least two-thirds of the then
outstanding voting securities of the Corporation, voting together as a single
class, shall be required for the amendment, repeal or modification of the
provisions of Article IX, Article X or Article XII of this Amended and Restated
Certificate of Incorporation or Sections 2.3 (Special Meeting), 2.4 (Notice of
Stockholders' Meeting), 2.5 (Advanced Notice of Stockholder Nominees and
Stockholder Business), 2.10 (Voting), or 2.12 (Stockholder Action by Written
Consent Without a Meeting), or 3.2 (Number of Directors) of the Corporation's
Bylaws.

                                  ARTICLE XII

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

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         IN WITNESS WHEREOF, the Corporation has caused this Restated
Certificate of Incorporation to be signed by its Chief Executive Officer and
President on October 17th, 2000.

                                     Introgen Therapeutics, Inc.

                                     /s/ DAVID G. NANCE
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                                     David G. Nance
                                     Chief Executive Officer and President




















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