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                  AMENDED AND RESTATED CERTIFICATE OF INCORPORATION
                          OF COLLATERAL THERAPEUTICS, INC.,
                                A DELAWARE CORPORATION

     Collateral Therapeutics, Inc., a corporation organized and existing under
the laws of the State of Delaware, hereby certifies as follows:

     1.   The name of the corporation is Collateral Therapeutics, Inc.  The
original Certificate of Incorporation of the corporation was filed with the
Secretary of State of the State of Delaware on April 16, 1998 and was amended
pursuant to a Certificate of Amendment of Certificate of Incorporation of the
Corporation filed with the Secretary of State of the State of Delaware on
May 29, 1998, as corrected by Corrected Certificate of Amendment of the
Certificate of Incorporation filed with the Secretary of State of Delaware on
June 2, 1998.

     2.   Pursuant to Sections 242 and 245 of the General Corporation Law of the
State of Delaware, the Amended and Restated Certificate of Incorporation was
adopted by the corporation's Board of Directors and stockholders, the
stockholders of the corporation having approved the Amended and Restated
Certificate of Incorporation by the written consent of the holders of at least a
majority of the outstanding shares in accordance with Section 228 thereof, and
written notice having been given in accordance with the requirements of such
Section.  The Amended and Restated Certificate of Incorporation restates,
integrates and amends the provisions of the Certificate of Incorporation of this
corporation.

     3.   The text of the Certificate of Incorporation as heretofore amended or
supplemented is hereby restated and further amended to read in its entirety as
follows:

                                      ARTICLE I

     The name of this corporation is Collateral Therapeutics, Inc.

                                      ARTICLE II

     The address of this corporation's registered office in the State of
Delaware is 30 Old Rudnick Lane, City of Dover, County of Kent 19901.  The name
of its registered agent at such address is CorpAmerica, Inc.

                                     ARTICLE III

     The purpose of this corporation is to engage in any lawful act or activity
for which a corporation may now or hereafter be organized under the Delaware
General Corporation Law.

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                                      ARTICLE IV

     (A)  CLASSES OF STOCK.  This corporation is authorized to issue two classes
of stock, denominated Common Stock and Preferred Stock.  The Common Stock shall
have a par value of $0.001 per share and the Preferred Stock shall have a par
value of $0.001 per share.  The total number of shares of Common Stock which the
Corporation is authorized to issue is Forty Million (40,000,000), and the total
number of shares of Preferred Stock which the Corporation is authorized to issue
is Five Million (5,000,000), which shares of Preferred Stock shall be
undesignated as to series.

     (B)  ISSUANCE OF PREFERRED STOCK.  The Preferred Stock may be issued from
time to time in one or more series.  The Board of Directors is hereby
authorized, by filing one or more certificates pursuant to the Delaware General
Corporation Law (each, a "Preferred Stock Designation"), to fix or alter from
time to time the designations, powers, preferences and rights of each such
series of Preferred Stock and the qualifications, limitations or restrictions
thereof, including without limitation the dividend rights, dividend rate,
conversion rights, voting rights, rights and terms of redemption (including
sinking fund provisions), redemption price or prices, and the liquidation
preferences of any wholly-unissued series of Preferred Stock, and to establish
from time to time the number of shares constituting any such series and the
designation thereof, or any of them; and to increase or decrease the number of
shares of any series subsequent to the issuance of shares of that series, but
not below the number of shares of such series then outstanding.  In case the
number of shares of any series shall be decreased in accordance with the
foregoing sentence, the shares constituting such decrease shall resume the
status that they had prior to the adoption of the resolution originally fixing
the number of shares of such series.

     (C)  RIGHTS, PREFERENCES, PRIVILEGES AND RESTRICTIONS OF COMMON STOCK.  

     1.   DIVIDEND RIGHTS.  Subject to the prior or equal rights of holders of
all classes of stock at the time outstanding having prior or equal rights as to
dividends, the holders of the Common Stock shall be entitled to receive, when
and as declared by the Board of Directors, out of any assets of the corporation
legally available therefor, such dividends as may be declared from time to time
by the Board of Directors.

     2.   REDEMPTION.  The Common Stock is not redeemable upon demand of any
holder thereof or upon demand of this corporation.

     3.   VOTING RIGHTS.  The holder of each share of Common Stock shall have
the right to one vote, and shall be entitled to notice of any stockholders'
meeting in accordance with the Bylaws of this corporation, and shall be entitled
to vote upon such matters and in such manner as may be provided by law.

                                      ARTICLE V

     (A)  EXCULPATION.  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, 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 


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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 any
improper personal benefit.  If the Delaware General Corporation Law is hereafter
amended to further reduce or to authorize, with the approval of the
corporation's stockholders, further reductions in the liability of the
corporation's directors for breach of fiduciary duty, then a director of the
corporation shall not be liable for any such breach to the fullest extent
permitted by the Delaware General Corporation Law as so amended.

     (B)  INDEMNIFICATION.  To the extent permitted by applicable law, this
corporation is also authorized to provide indemnification of (and advancement of
expenses to) such agents (and any other persons to which Delaware law permits
this corporation to provide indemnification) through bylaw provisions,
agreements with such agents or other persons, vote of stockholders or
disinterested directors or otherwise, in excess of the indemnification and
advancement otherwise permitted by Section 145 of the Delaware General
Corporation Law, subject only to limits created by applicable Delaware law
(statutory or non-statutory), with respect to actions for breach of duty to the
corporation, its stockholders, and others.

     (C)  EFFECT OF REPEAL OR MODIFICATION.  Any repeal or modification of any
of the foregoing provisions of this Article V shall be prospective and shall not
adversely affect any right or protection of a director, officer, agent or other
person existing at the time of, or increase the liability of any director of the
corporation with respect to any acts or omissions of such director occurring
prior to, such repeal or modification.

                                      ARTICLE VI

     Elections of directors need not be by written ballot except and to the
extent provided in the Bylaws of the corporation.  The number of directors shall
be as specified in the Bylaws of the corporation.  In no event will the number
of directors be less than three.  Directors need not be stockholders.

                                     ARTICLE VII

     No holder of shares of stock of the corporation shall have any preemptive
or other right, except as such rights are expressly provided by contract, to
purchase or subscribe for or receive any shares of any class, or series thereof,
of stock of the corporation, whether now or hereafter authorized, or any
warrants, options, bonds, debentures or other securities convertible into,
exchangeable for or carrying any right to purchase any share of any class, or
series thereof, of stock; but such additional shares of stock and such warrants,
options, bonds, debentures or other securities convertible into, exchangeable
for or carrying any right to purchase any shares of any class, or series
thereof, of stock may be issued or disposed of by the Board of Directors to such
persons, and on such terms and for such lawful consideration as in its
discretion it shall deem advisable or as the corporation shall have by contract
agreed.

                                     ARTICLE VIII

     The corporation is to have a perpetual existence.


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                                      ARTICLE IX

     The corporation reserves the right to repeal, alter, amend or rescind any
provision contained in this Amended and Restated Certificate of Incorporation
and/or any provision contained in any amendment to or restatement of this
Amended and Restated Certificate of Incorporation, in the manner now or
hereafter prescribed by statute, and all rights conferred on stockholders herein
are granted subject to this reservation.

                                      ARTICLE X

     The Board of Directors may from time to time make, amend, supplement or
repeal the Bylaws by the requisite affirmative vote of Directors as set forth in
the Bylaws; provided, however, that the stockholders may change or repeal any
bylaw adopted by the Board of Directors by the requisite affirmative vote of
stockholders as set forth in the Bylaws; and, provided further, that no
amendment or supplement to the Bylaws adopted by the Board of Directors shall
vary or conflict with any amendment or supplement thus adopted by the
stockholders.

                                      ARTICLE XI

     No action shall be taken by the stockholders of the corporation except at
an annual or special meeting of stockholders called in accordance with the
Bylaws, and no action shall be taken by the stockholders by written consent.

                                     ARTICLE XII

     Advance notice of stockholder nominations for the election of directors and
of business to be brought by stockholders before any meeting of the stockholders
of the corporation shall be given in the manner provided in the Bylaws of the
corporation.

                                     ARTICLE XIII

     This document shall be effective as of July 8, 1998 at 7:00 a.m. pacific
daylight savings time.




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     IN WITNESS WHEREOF, Collateral Therapeutics, Inc., has caused this
certificate to be signed by Jack W. Reich, Ph.D., its President and Chief
Executive Officer, this 7th day of July, 1998.

                                COLLATERAL THERAPEUTICS, INC.




                                By: /s/ Jack W. Reich, Ph.D.
                                    Jack W. Reich, Ph.D.
                                    President and Chief Executive Officer

















[SIGNATURE PAGE TO AMENDED AND RESTATED CERTIFICATE OF
INCORPORATION OF COLLATERAL THERAPEUTICS, INC.]