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                                                                  EXHIBIT 3.1(b)


                           CERTIFICATE OF AMENDMENT TO
                         CERTIFICATE OF INCORPORATION OF
                           INTROGEN THERAPEUTICS, INC.

                                   ----------

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

          1. That Article XI of the Corporation's Restated Certificate of
Incorporation which currently reads:

         "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."

is amended to read as follows:

         "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 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) of the Corporation's Bylaws. 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 by the stockholders of Section 3.2 (Number of Directors) of the
Corporation's Bylaws."

         2. This Certificate of Amendment of the Corporation's Restated
Certificate of Incorporation has been duly approved by the Corporation's Board
of Directors in accordance with Section 228 the Delaware General Corporation
Law.

         3. This Certificate of Amendment of the Corporation's Restated
Certificate of Incorporation has been duly approved by the required vote of
stockholders in accordance with Section 242 of the Delaware General Corporation
Law.



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         IN WITNESS WHEREOF, the Corporation has caused this Certificate of
Amendment to be signed by its Chief Executive Officer and President, this 5th
day of December, 2001.

                                     Introgen Therapeutics, Inc.

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







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