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                              FORM OF PURCHASE AGREEMENT

          THIS AGREEMENT (the "Agreement") is made as of the 6th day of
August, 1999, by and among Collateral Therapeutics Inc. (the "Company"), a
corporation organized under the laws of the State of Delaware, with its
principal offices at 11622 El Camino Real, San Diego, California 92130, and
the purchaser whose name and address is set forth on the signature page
hereof (the "Purchaser").

          IN CONSIDERATION of the mutual covenants contained in this Agreement,
the Company, and the Purchaser agree as follows:

SECTION 1.     AUTHORIZATION OF SALE OF THE SHARES.  Subject to the terms and
conditions of this Agreement, the Company has authorized the sale of up to
2,150,000 shares (the "Shares") of the common stock, par value $0.001 per share
(the "Common Stock"), of the Company.

SECTION 2.     AGREEMENT TO SELL AND PURCHASE THE SHARES.  At the Closing (as
defined in Section 3), the Company will, subject to the terms of this Agreement,
sell to the Purchaser, and the Purchaser will buy from the Company, upon the
terms and conditions hereinafter set forth, the number of Shares (at the
purchase price) set forth on the signature page hereof:

          The Company proposes to enter into this same form of purchase
agreement with the other investors (the "Other Purchasers") and to complete
sales of the Shares to them. The Purchaser and the Other Purchasers are
hereinafter sometimes collectively referred to as the "Purchasers," and this
Agreement and the agreements executed by the Other Purchasers are hereinafter
sometimes collectively referred to as the "Agreements." The term "Placement
Agent" shall mean Bear, Stearns & Co. Inc.

SECTION 3.     DELIVERY OF THE SHARES AT THE CLOSING.  The "Subscription Date"
shall be the date when the Company has notified the Placement Agent in writing
that it is no longer accepting Purchase Agreements from investors.  The
completion of the purchase and sale of the Shares (the "Closing") shall occur at
a place and time (the "Closing Date") to be determined by the Company and the
Placement Agent, which date shall not be less than three nor more than ten
business days after the Subscription Date. The Purchasers will be notified by
facsimile transmission or otherwise of the Closing Date.

          At the Closing, the Company shall issue to the Purchaser one or more
stock certificates registered in the name of the Purchaser, or in such nominee
name(s) as designated by the Purchaser in writing, representing the number of
Shares set forth in Section 2 above. The name(s) in which the stock certificates
are to be registered are set forth in the Stock Certificate Questionnaire
attached hereto as part of Appendix 1. The Company's obligation to complete the
purchase and sale of the Shares and deliver such stock certificate(s) to the
Purchaser at the Closing shall be subject to the following conditions, any one
or more of which may be waived by the Company:  (a) receipt by the Company of
same-day funds in the full amount of the purchase price for the Shares being
purchased hereunder; (b) completion of the purchases and sales under the
Agreements with all of the Other Purchasers; and (c) the accuracy of the
representations and warranties made by the Purchasers and the fulfillment of
those undertakings of the Purchasers to be fulfilled prior to the Closing.  The
Purchaser's obligation to accept delivery of such stock

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certificate(s) and to pay for the Shares evidenced thereby shall be subject
to the accuracy in all material respects of the representations and
warranties made by the Company herein and the fulfillment in all material
respects of those undertakings of the Company to be fulfilled prior to
Closing. The Purchaser's obligations hereunder are expressly conditioned on
the purchase by  Other Purchasers of the Shares that they have agreed to
purchase from the Company to the extent that the Purchaser's Shares, in
combination with Shares purchased by Other Purchasers, shall total at least
2.0 million Shares.

SECTION 4.     REPRESENTATIONS, WARRANTIES AND COVENANTS OF THE COMPANY.  The
Company hereby represents and warrants to, and covenants with, the Purchaser as
follows:

     4.1  ORGANIZATION AND QUALIFICATION.  The Company is a corporation duly
organized, validly existing and in good standing under the laws of its
jurisdiction of incorporation and is qualified to do business as a foreign
corporation in each jurisdiction in which qualification is required, except
where failure to so qualify would not have a Material Adverse Effect (as defined
herein) on the Company.

     4.2  AUTHORIZED CAPITAL STOCK.  Except as described by the Confidential
Private Placement Memorandum dated July 21, 1999 prepared by the Company,
including all Exhibits (except for this Agreement), the Supplemental Package(s)
(as defined therein), amendments and any other documents incorporated by
reference thereto (the "Private Placement Memorandum"), the Company had
authorized and outstanding capital stock as set forth under the heading
"Capitalization" in the Private Placement Memorandum as of the date set forth
therein; the issued and outstanding shares of the Company's Common Stock have
been duly authorized and validly issued, are fully paid and nonassessable, have
been issued in compliance with all federal and state securities laws, were not
issued in violation of or subject to any preemptive rights or other rights to
subscribe for or purchase securities and conform in all material respects to any
descriptions thereof contained in the Private Placement Memorandum.  Except as
described by the Private Placement Memorandum and except with respect to the
issuance of options under the Company's 1998 Stock Incentive Plan and the
issuance of shares of Common Stock pursuant to the Company's Employee Stock
Purchase Plan and pursuant to any options outstanding as of the date hereof, the
Company does not have outstanding any options to purchase, or any preemptive
rights or other rights to subscribe for or to purchase, or any contracts or
commitments to issue or sell, any securities or obligations convertible into
shares of its capital stock or any shares of capital stock of any subsidiary.
The description of the Company's stock, stock bonus and other stock plans or
arrangements and the options or other rights granted and exercised thereunder,
set forth in the documents incorporated by reference in the Private Placement
Memorandum accurately and fairly presents the information required to be shown
with respect to such plans, arrangements, options and rights.

     4.3  ISSUANCE, SALE AND DELIVERY OF THE SHARES.  The Shares have been duly
authorized and, when issued, delivered and paid for in the manner set forth in
this Agreement, will be duly authorized, validly issued, fully paid and
nonassessable, and will conform in all material respects to the description
thereof set forth in the Private Placement Memorandum. No preemptive rights or
other rights to subscribe for or purchase exist with respect to the issuance and
sale of the Shares by the Company pursuant to this Agreement. No stockholder of
the Company has any right (which has not been waived or has not expired by
reason of lapse of time following

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notification of the Company's intent to file the registration statement to be
filed by the Company pursuant to Section 7.1 hereof (the "Registration
Statement")) to require the Company to register the sale of any shares owned
by such stockholder under the Securities Act of 1933, as amended (the
"Securities Act"), in the Registration Statement. No further approval or
authority of the stockholders, or the Board of Directors of the Company will
be required for the issuance and sale of the Shares to be sold by the Company
as contemplated herein.  The Company's issuance of the Shares shall be in
compliance with all applicable Federal, state securities or blue sky laws.

     4.4  DUE EXECUTION, DELIVERY AND PERFORMANCE OF THE AGREEMENTS.  The
Company has full legal right, corporate power and authority to enter into the
Agreements and perform the transactions contemplated hereby. The Agreements have
been duly authorized, executed and delivered by the Company. The making and
performance of the Agreements by the Company and the consummation of the
transactions herein contemplated will not violate any provision of the
organizational documents of the Company.  The making and performance of the
Agreements by the Company and the consummation of the transactions herein
contemplated will not (i) result in the creation of any lien, charge, security
interest or encumbrance upon any assets of the Company pursuant to the terms or
provisions of, or (ii) conflict with, result in the breach or violation of, or
constitute, either by itself or upon notice or the passage of time or both, a
default under any material agreement, mortgage, deed of trust, lease, franchise,
license, indenture, permit or other instrument to which the Company is a party
or by which the Company or any of its respective properties may be bound or
affected, or, to the Company's knowledge, any statute or any authorization,
judgment, decree, order, rule or regulation of any court or any regulatory body,
administrative agency or other governmental body applicable to the Company or
any of its respective properties and, in each case (i) or (ii), which
individually or in the aggregate would have a material adverse effect on the
condition (financial or otherwise), properties, business, prospects as of the
date hereof or results of operations of the Company, taken as a whole (a
"Material Adverse Effect"). No consent, approval, authorization or other order
of any court, regulatory body, administrative agency or other governmental body
is required for the execution and delivery of this Agreement or the consummation
of the transactions contemplated by this Agreement, except for compliance with
the Blue Sky laws and federal securities laws applicable to the offering of the
Shares. Upon their execution and delivery, and assuming the valid execution
thereof by the respective Purchasers, the Agreements will constitute valid and
binding obligations of the Company, enforceable in accordance with their
respective terms, except as enforceability may be limited by applicable
bankruptcy, insolvency, reorganization, moratorium or similar laws affecting
creditors' and contracting parties' rights generally and except as
enforceability may be subject to general principles of equity (regardless of
whether such enforceability is considered in a proceeding in equity or at law)
and except as the indemnification agreements of the Company in Section 7.3
hereof may be legally unenforceable.

     4.5  ACCOUNTANTS.  Ernst & Young LLP, who have expressed their opinion with
respect to the financial statements to be incorporated by reference from the
Company's Annual Report on Form 10-K for the year ended December 31, 1998 into
the Registration Statement and the Prospectus which forms a part thereof, are
independent accountants as required by the Securities Act and the rules and
regulations promulgated thereunder (the "Rules and Regulations").

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     4.6  NO DEFAULTS.  Except as to defaults, violations and breaches which
individually or in the aggregate would not have a Material Adverse Effect, the
Company is not in violation or default of any provision of its certificate of
incorporation or bylaws, or other organizational documents, or in breach of or
default with respect to any provision of any agreement, judgment, decree, order,
mortgage, deed of trust, lease, franchise, license, indenture, permit or other
instrument to which it is a party or by which it or any of its properties are
bound; and there does not exist any state of fact which, with notice or lapse of
time or both, would constitute an event of default as defined in such documents
on the part of the Company, except such defaults which individually or in the
aggregate would not have a Material Adverse Effect.

     4.7  CONTRACTS.  The contracts described in the Private Placement
Memorandum or incorporated by reference therein that are material to the Company
are in full force and effect on the date hereof, and neither the Company nor, to
the Company's knowledge, any other party to such contracts is in breach of or
default under any of such contracts which would have a Material Adverse Effect.

     4.8  NO ACTIONS.  Except as disclosed in the Private Placement Memorandum,
there are no legal or governmental actions, suits or proceedings pending or, to
the Company's knowledge, threatened to which the Company is or may be a part or
of which property owned or leased by the Company is or may be the subject, or
related to environmental or discrimination matters, which actions, suits or
proceedings, individually or in the aggregate, might prevent or might reasonably
be expected to materially and adversely affect the transactions contemplated by
this Agreement or result in a Material Adverse Effect; and no labor disturbance
by the employees of the Company exists, or, to the Company's knowledge, is
threatened which might reasonably be expected to have a Material Adverse Effect.
Except as disclosed in the Private Placement Memorandum, the Company is not a
party to or subject to the provisions of any material injunction, judgment,
decree or order of any court, regulatory body administrative agency or other
governmental body.

     4.9  PROPERTIES.  The Company has good and marketable title to all the
properties and assets reflected as owned by it in the financial statements
included in or incorporated by reference into the Private Placement Memorandum,
subject to no lien, mortgage, pledge, charge or encumbrance of any kind except
(i) those, if any, reflected in such financial statements, (ii) those of the
United States Government to exercise rights with respect to inventions made with
Government support, or (iii) those which are not material in amount and do not
adversely affect the use made and promised to be made of such property by the
Company.  The Company holds its leased properties under valid and binding
leases, with such exceptions as are not materially significant in relation to
their respective businesses. Except as disclosed in the Private Placement
Memorandum, the Company owns or leases all such properties as are necessary to
its operations as now conducted.

     4.10 NO MATERIAL CHANGE.  Since June 30, 1999 and except as addressed by
the Private Placement Memorandum, (i) the Company has not incurred any material
liabilities or obligations, indirect, or contingent, or entered into any
material oral or written agreement or other transaction which is not in the
ordinary course of business or which could reasonably be expected to result in a
material reduction in the future earnings of the Company or other Material
Adverse Effect; (ii) the Company has not sustained any material loss or
interference with its

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businesses or properties from fire, flood, windstorm, accident or other
calamity not covered by insurance; (iii) the Company has not paid or declared
any dividends or other distributions with respect to its capital stock and
the Company is not in default in the payment of principal or interest on any
outstanding debt obligations; (iv) there has not been any change in the
capital stock of the Company other than the sale of the Shares hereunder and
shares or options issued pursuant to the Company's 1998 Stock Incentive Plan,
the Company's Employee Stock  Purchase Plan and any options outstanding as of
the date hereof, or indebtedness, liens or claims material to the Company
(other than in the ordinary course of business); and (v) except for the
operating losses and negative cash flow the Company has continued to incur,
there has not been a material adverse change in the condition (financial or
otherwise), properties, business, prospects as of the date hereof or results
of operations of the Company.

     4.11 INTELLECTUAL PROPERTY.  Except as addressed by the Private Placement
Memorandum, the Company believes it has the necessary trademark, trade name
rights, patent rights, copyrights, licenses and trade secret rights to conduct
its business as it is now being conducted and as specifically described in the
Private Placement Memorandum; and, except as described in the Private Placement
Memorandum under "Business," the Company has no knowledge of any material
infringement by it of the trademark, trade name rights, patent rights,
copyrights or trade secret rights of others, or of any claim made against the
Company regarding trademark, trade name, patent or trade secret infringement,
that would be expected to have a material adverse effect on the Company.  The
foregoing is subject to and must be considered in view of the numerous
uncertainties and complexities inherent in seeking intellectual property
protection of sufficient scope to protect the Company's technologies, in
defending intellectual property rights that may be obtained, and in avoiding or
being able to license or defend against intellectual property rights that may
belong to or may be acquired by others; see the discussion of Risks Related to
Patents and Proprietary Information in the Private Placement Memorandum.

     4.12 COMPLIANCE.  The Company has not been advised, and has no reason to
believe, that it is not conducting business in compliance with all applicable
laws, rules and regulations of the jurisdictions in which it is conducting
business, including, without limitation, all applicable local, state and federal
environmental laws and regulations; except where failure to be so in compliance
would not have a Material Adverse Effect.

     4.13 TAXES.  The Company has filed all necessary federal, state and foreign
income and franchise tax returns and has paid or accrued all taxes shown as due
thereon, and the Company has no knowledge of a tax deficiency which has been or
might be asserted or threatened against it which would have a Material Adverse
Effect.

     4.14 TRANSFER TAXES.  On the Closing Date, all stock transfer or other
taxes (other than income taxes) which are required to be paid in connection with
the sale and transfer of the Shares to be sold to the Purchaser hereunder will
be, or will have been, fully paid or provided for by the Company and all laws
imposing such taxes will be or will have been fully complied with.

     4.15 INVESTMENT COMPANY.  The Company is not an "investment company" or an
"affiliated person" of, or "promoter" or "principal underwriter" for an
investment company, within the meaning of the Investment Company Act of 1940, as
amended.

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     4.16 OFFERING MATERIALS.  The Company has not distributed and will not
distribute prior to the Closing Date any offering material in connection with
the offering and sale of the Shares other than the Private Placement Memorandum.
The Company has not in the past nor will it hereafter take any action
independent of the Placement Agent to sell, offer for sale or solicit offers to
buy any securities of the Company which would bring the offer, issuance or sale
of the Shares, as contemplated by this Agreement, within the provisions of
Section 5 of the Securities Act, unless such offer, issuance or sale was or
shall be within the exemptions of Section 4 of the Securities Act.

     4.17 INSURANCE.  Except as disclosed in the Private Placement Memorandum,
the Company maintains and will continue to maintain insurance of the types and
in the amounts that the Company reasonably believes is adequate for its
business, including, but not limited to, insurance covering all real and
personal property owned or leased by the Company against theft, damage,
destruction, acts of vandalism and all other risks customarily insured against
by similarly situated companies, all of which insurance is in full force and
effect.

     4.18 CONTRIBUTIONS.  The Company has not at any time since its
incorporation, directly or indirectly, (i) made any unlawful contribution to any
candidate for public office, or failed to disclose fully any contribution in
violation of law, or (ii) made any payment to any federal or state governmental
officer or official, or other person charged with similar public or quasi-public
duties, other than payments required or permitted by the laws of the United
States or any jurisdiction thereof.

     4.19 REPORTING COMPANY; LISTED SECURITIES.  The Company is a reporting
company and has filed all reports required to be filed by Sections 13(a), 14(a)
or 15(d) of the Securities Exchange Act of 1934, as amended (the "Exchange Act")
in a timely manner during the preceding twelve (12) months and has been subject
to such filing requirements for the past twelve (12) months.  The Common Stock
is quoted on the Nasdaq National Market System ("Nasdaq").  To the Company's
knowledge, there is no stop order suspending the trading of the Common Stock on
Nasdaq or any information which would result in the Common Stock from being
delisted from Nasdaq.  The Company will continue to use commercially reasonable
efforts to satisfy the Non-Quantitative Designation Criteria contained in
Section 5 of Part III of Schedule D of the NASD's Bylaws to the extent such
criteria are within the control of the Company.  Nothing in this Section shall
be interpreted to preclude the Company from listing its Common stock on a
national securities exchange in lieu of the Nasdaq National Market.

     4.20 ADDITIONAL INFORMATION.  The Company represents and warrants that the
information contained in the following documents, which the Placement Agent has
furnished to the Purchaser, or will furnish prior to the Closing, complies in
all material respects with the Rules and Regulations and is, or will be, true
and complete in all material respects as of their respective filing dates:

          (a)  the Company's Annual Report on Form 10-K for the fiscal year
ended December 31, 1998 (without exhibits);

          (b)  the Company's Quarterly Report on Form 10-Q for the fiscal
quarter ended June 30, 1999 (without exhibits);

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          (c)  the Company's Proxy Statement for the 1999 Annual Meeting of
Stockholders;

          (d)  the Registration Statement;

          (e)  the Private Placement Memorandum (other than the Purchase
Agreement and appendices thereto); and

          (f)  all other documents, if any, filed by the Company with the
Securities and Exchange Commission (the "SEC") since December 31, 1998 pursuant
to the reporting requirements of the Exchange Act.

     4.21 LEGAL OPINION.  Prior to the Closing, Brobeck, Phleger & Harrison LLP,
counsel to the Company, will deliver its legal opinion to the Placement Agent
reasonably satisfactory to the Placement Agent and counsel to the Placement
Agent.  Such opinion shall also state that each of the Purchasers may rely
thereon as though it were addressed directly to such Purchaser.

     4.22 CERTIFICATE.  At the Closing, the Company will deliver to Purchaser a
certificate executed by the Chairman of the Board or President and the chief
financial or accounting officer of the Company, dated the Closing Date, in form
and substance reasonably satisfactory to the Purchasers, to the effect that the
representations and warranties of the Company set forth in this Section 4 are
true and correct in all material respects as of the date of this Agreement and
as of the Closing Date, and the Company has complied with all the agreements and
satisfied all the conditions herein on its part to be performed or satisfied on
or prior to such Closing Date.

SECTION 5.     REPRESENTATIONS, WARRANTIES AND COVENANTS OF THE PURCHASER.

          (a)  The Purchaser represents and warrants to, and covenants with, the
Company that:  (i) the Purchaser is knowledgeable, sophisticated and experienced
in making, and is qualified to make, decisions with respect to investments in
shares representing an investment decision like that involved in the purchase of
the Shares, including investments in securities issued by the Company, and has
requested, received, reviewed and considered all information it deems relevant
in making an informed decision to purchase the Shares; (ii) the Purchaser is
acquiring the number of Shares set forth in the signature page hereto, for its
own account for investment (as defined for purposes of the Hart-Scott-Rodino
Antitrust Improvement Act of 1976 and the regulations thereunder) only and with
no present intention of distributing any of such Shares or any arrangement or
understanding with any other persons regarding the distribution of such Shares;
(iii) the Purchaser will not, directly or indirectly, offer, sell, pledge,
transfer or otherwise dispose of (or solicit any offers to buy, purchase or
otherwise acquire or take a pledge of) any of the Shares except in compliance
with the Act, the Rules and Regulations and any applicable state securities or
blue sky laws; (iv) the Purchaser has completed or caused to be completed the
Registration Statement Questionnaire and the Stock Certificate Questionnaire,
both attached hereto as Appendix I, for use in preparation of the Registration
Statement, and the answers thereto are true and correct as of the date hereof
and will be true and correct as of the effective date of the Registration
Statement; (v) the Purchaser has, in connection with its decision to purchase
the number of Shares set forth in Section 2 above, not relied upon any
representations or other information (whether oral or written) other than as set
forth in the

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Private Placement Memorandum and the documents included therein and the
representations and warranties of the Company contained herein; (vi) the
Purchaser has had an opportunity to discuss this investment with
representatives of the Company and ask questions of them; and (vii) the
Purchaser is an "accredited investor" within the meaning of Rule 501 of
Regulation D promulgated under the Securities Act.

          (b)  The Purchaser hereby covenants with the Company not to make any
sale of the Shares without satisfying the prospectus delivery requirement under
the Securities Act, and the Purchaser acknowledges and agrees that such Shares
are not transferable on the books of the Company unless the certificate
submitted to the transfer agent evidencing the Shares is accompanied by a
separate officer's certificate: (i) in the form of Appendix II hereto,
(ii) executed by an officer of, or other authorized person designated by, the
Purchaser, and (iii) to the effect that (A) the Shares have been sold in
accordance with the Registration Statement, the Securities Act and the Rules and
Regulations and any applicable state securities or blue sky laws and (B) the
requirement of delivering a current prospectus has been satisfied, except to the
extent that the requirement of delivering a current prospectus is inapplicable
under the Rules and Regulations as applied to: (i) a transfer to an affiliate of
the Purchaser (including a mutual fund with a common investment advisor) that is
carried out in accordance with an applicable exemption from registration under
the Securities Act and the Rules and Regulations, or (ii) a transfer or sale
pursuant to Rule 144 or another applicable exemption from registration under the
Securities Act and the Rules and Regulations. The Purchaser acknowledges that
there may occasionally be times when the Company must suspend the use of the
prospectus forming a part of the Registration Statement until such time as an
amendment to the Registration Statement has been filed by the Company and
declared effective by the SEC, or until such time as the Company has filed an
appropriate report with the SEC pursuant to the Exchange Act. The Purchaser
hereby covenants that it will not sell any Shares pursuant to said prospectus
during the period commencing at the time at which the Company gives the
Purchaser written notice of the suspension of the use of said prospectus and
ending at the time the Company gives the Purchaser written notice that the
Purchaser may thereafter effect sales pursuant to said prospectus; provided,
however, that the Company will deliver such notices to Purchaser as promptly as
practicable and will use commercially reasonable and diligent efforts to limit
the aggregate duration of such suspensions to forty-five (45) days per calendar
year. The Purchaser further covenants to notify the Company promptly of the sale
of all of its Shares.

          (c)  The Purchaser further represents and warrants to, and covenants
with, the Company that (i) the Purchaser has full right, power, authority and
capacity to enter into this Agreement and to consummate the transactions
contemplated hereby and has taken all necessary action to authorize the
execution, delivery and performance of this Agreement, (ii) if applicable, the
Purchaser is duly organized, validly existing and in good standing under the
laws of its jurisdiction, (iii) the making and performance of the Agreement by
Purchaser and the consummation of the transactions herein contemplated will not
violate any provision of the organizational documents of Purchaser or conflict
with, result in the breach or violation of, or constitute, either by itself or
upon notice or the passage of time or both, a default under any material
agreement, mortgage, deed of trust, lease, franchise, license, indenture, permit
or other instrument to which the Purchaser is a party or, any statute or any
authorization, judgment, decree, order, rule or regulation of any court or any
regulatory body, administrative agency or other governmental body applicable to
Purchaser, (iv) no consent, approval, authorization or

<PAGE>

other order of any court, regulatory body, administrative agency or other
governmental body is required on the part of the Purchaser for the execution
and delivery of this Agreement or the consummation of the transactions
contemplated by this Agreement, and (v) upon the execution and delivery of
this Agreement, this Agreement shall constitute a valid and binding
obligation of the Purchaser enforceable in accordance with its terms, except
as enforceability may be limited by applicable bankruptcy, insolvency,
reorganization, moratorium or similar laws affecting creditors' and
contracting parties' rights generally and except as enforceability may be
subject to general principles of equity (regardless of whether such
enforceability is considered in a proceeding in equity or at law) and except
as the indemnification agreements of the Purchaser in Section 7.3 hereof may
be legally unenforceable and (vi) there is not in effect any order enjoining
or restraining the Purchaser from entering into or engaging in any of the
transactions contemplated by this Agreement.

          (d)  The Purchaser recognizes that an investment in the Shares
involves a high degree of risk, including a risk of total loss of Purchaser's
investment, and the Purchaser has full cognizance of and understands all of the
risk factors related to Purchaser's purchase of the Shares, including, but not
limited to, those set forth under the caption "Risk Factors" in the Private
Placement Memorandum.

          (e)  All of the information provided to the Company or its agents or
representatives concerning the Purchaser's suitability to invest in the Company
and the representations and warranties contained herein, are complete, true and
correct as of the date hereof.  Purchaser understands that the Company is
relying on the statements contained herein to establish an exemption from
registration under federal and state securities laws.

          (f)  The address set forth in the signature page hereto is the
Purchaser's true and correct residence and the Purchaser has no present
intention of becoming a resident of any other state or jurisdiction.

          (g)  The Purchaser covenants to provide Company at all times as the
Company is required to keep the Registration Statement in effect with an
updated, accurate and complete plan of distribution.

          (h)  The Purchaser understands and agrees that each certificate or
other document evidencing any of the Shares shall be endorsed with the legend in
substantially the form set forth below as well as any other legends required by
applicable law and the Purchaser covenants that the Purchaser shall not transfer
the shares represented by any such certificate without complying with the
restrictions on transfer described in the legends endorsed on such certificate
and understands that the Company shall refuse to register any transfer of Shares
not complying with the following legend:

<PAGE>

THE SECURITIES REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN REGISTERED UNDER
THE SECURITIES ACT OF 1933, AS AMENDED ("SECURITIES ACT"), OR REGISTERED OR
QUALIFIED UNDER ANY APPLICABLE STATE SECURITIES LAWS.  THESE SECURITIES MAY NOT
BE TRANSFERRED UNLESS (A) COVERED BY AN EFFECTIVE REGISTRATION STATEMENT UNDER
THE SECURITIES ACT AND REGISTERED OR QUALIFIED UNDER APPLICABLE STATE SECURITIES
LAWS OR (B) EXEMPTIONS FROM SUCH REGISTRATION OR QUALIFICATION REQUIREMENTS ARE
AVAILABLE.  AS A CONDITION TO PERMITTING ANY TRANSFER OF THESE SECURITIES, THE
COMPANY MAY REQUIRE THAT IT BE FURNISHED WITH AN OPINION OF COUNSEL REASONABLY
ACCEPTABLE TO THE COMPANY TO THE EFFECT THAT NO REGISTRATION OR QUALIFICATION IS
LEGALLY REQUIRED FOR SUCH TRANSFER

SECTION 6.     SURVIVAL OF REPRESENTATIONS, WARRANTIES AND AGREEMENTS.
Notwithstanding any investigation made by any party to this Agreement or by the
Placement Agent, all covenants, agreements, representations and warranties made
by the Company and the Purchaser herein and in the certificates for the Shares
delivered pursuant hereto shall survive for a period of two (2) years following
the execution of this Agreement, the delivery to the Purchaser of the Shares
being purchased and the payment therefor.

SECTION 7.     REGISTRATION OF THE SHARES;  COMPLIANCE WITH THE SECURITIES ACT.

     7.1  REGISTRATION PROCEDURES AND EXPENSES.  Except for such times as the
Company may be required to suspend the use of a prospectus forming a part of the
Registration Statement, as further described in Section 5(b) hereof, the Company
shall use its reasonable best efforts to:

          (a)  as soon as practicable, but in no event later than five (5)
business days following the Subscription Date, prepare and file with the SEC the
Registration Statement on Form S-3 relating to the resale of the Shares by the
Purchaser from time to time through the automated quotation system of Nasdaq or
the facilities of any national securities exchange on which the Common Stock is
then traded or in privately-negotiated transactions;

          (b)  subject to receipt of necessary information from the Purchasers,
cause the SEC to notify the Company of the SEC's willingness to declare the
Registration Statement effective within ninety (90) days after the Registration
Statement is filed by the Company, and notify the Purchasers of such
notification from the SEC within three (3) business days of receipt;

          (c)  promptly prepare and file with the SEC such amendments and
supplements to the Registration Statement and the prospectus used in connection
therewith as may be necessary to keep the Registration Statement effective until
the earlier of (i) the second anniversary of the Closing Date, (ii) the date on
which the Purchaser may sell all Shares then held by the Purchaser without
restriction by reason of Rule 144(k) under the Securities Act ("Rule 144") or
any other rule of similar effect, or (iii) such time as all Shares purchased by
the Purchaser have been sold pursuant to a registration statement;

          (d)  so long as the Registration Statement is effective covering the
resale of Shares owned by the Purchaser, furnish to the Purchaser with respect
to the Shares registered

<PAGE>

under the Registration Statement (and to each underwriter, if any, of such
Shares) such reasonable number of copies of prospectuses and such other
documents as the Purchaser may reasonably request, in order to facilitate the
public sale or other disposition of all or any of the Shares by the
Purchaser; provided, however, that the obligation of the Company to deliver
copies of prospectuses to the Purchaser shall be subject to the receipt by
the Company of reasonable assurances from the Purchaser that the Purchaser
will comply with the applicable provisions of the Securities Act and of such
other securities or blue sky laws as may be applicable in connection with any
use of such prospectuses;

          (e)  file documents required of the Company for normal blue sky
clearance in states specified in writing by the Purchaser; provided, however,
that the Company shall not be required to qualify to do business or consent to
service of process in any jurisdiction in which it is not now so qualified or
has not so consented;

          (f)  bear all expenses in connection with the procedures in paragraphs
(a) through (e) of this Section 7.1 and the registration of the Shares pursuant
to the Registration Statement, other than fees and expenses, if any, of counsel
or other advisers to the Purchaser or the Other Purchasers or underwriting
discounts, brokerage fees and commissions incurred by the Purchaser or the Other
Purchasers, if any; and

          (g)  with a view to making available to Purchaser the benefits of
Rule 144 (or its successor rule) and any other rule or regulation of the SEC
that may at any time permit Purchaser to sell Shares to the public without
registration, the Company covenants and agrees to:  (i) make and keep public
information available, as those terms are understood and defined in Rule 144,
until the earlier of (A) such date as all of Purchaser's Shares may be resold
within a given three-month period pursuant to Rule 144 or any other rule of
similar effect or (B) such date as all of Purchaser's Shares shall have been
resold; (ii) file with the SEC in a timely manner all reports and other
documents required of the Company under the Securities Act and under the
Exchange Act; and (iii) furnish to Purchaser upon request, as long as
Purchaser owns any Shares, (A) a written statement by the Company that it has
complied with the reporting requirements of the Securities Act and the
Exchange Act, (B) a copy of the most recent annual report on form 10-K or
quarterly report of the Company on form 10-Q, and (C) such other information
as may be reasonably requested in order to avail Purchaser of any rule or
regulation of the SEC that permits the selling of any such Shares without
registration.

     7.2  TRANSFER OF SHARES AFTER REGISTRATION.  The Purchaser agrees that it
will not effect any disposition of the Shares or its right to purchase the
Shares that would constitute a sale within the meaning of the Securities Act or
pursuant to any applicable state securities or blue sky laws, except as
contemplated in the Registration Statement referred to in Section 7. 1. and that
it will promptly notify the Company of any changes in the information set forth
in the Registration Statement regarding the Purchaser or its Plan of
Distribution, except to the extent that this Section 7.2 is inapplicable to a
transfer to an affiliate of the Purchaser (including a mutual fund with a common
investment advisor) that is carried out in accordance with an applicable
exemption from registration under the Securities Act and the Rules and
Regulations.

<PAGE>


     7.3  INDEMNIFICATION.  For the purpose of this Section 7.3:

               (i)  the term "Purchaser" shall include the Purchaser and any
affiliate of such Purchaser; and

               (ii) the term "Registration Statement" shall include any final
prospectus, exhibit, supplement or amendment included in or relating to the
Registration Statement referred to in Section 7.1.

          (a)  The Company agrees to indemnify and hold harmless each of the
Purchasers and each person, if any, who controls any Purchaser within the
meaning of the Securities Act, against any losses, claims, damages, liabilities
or expenses, joint or several, to which such Purchasers or such controlling
persons may become subject, under the Securities Act, the Exchange Act, or any
other federal or state statutory law or regulation, or at common law or
otherwise (including in settlement of any litigation, if such settlement is
effected with the written consent of the Company), insofar as such losses,
claims, damages, liabilities or expenses (or actions in respect thereof as
contemplated below) arise out of or are based upon any untrue statement or
alleged untrue statement of any material fact contained in the Registration
Statement, including the prospectus, financial statements and schedules, and all
other documents filed as a part thereof, as amended at the time of effectiveness
of the Registration Statement, including any information deemed to be a part
thereof as of the time of effectiveness pursuant to paragraph (b) of Rule 430A,
or pursuant to Rule 434, of the Rules and Regulations, or the prospectus, in the
form first filed with the SEC pursuant to Rule 424(b) of the Regulations, or
filed as part of the Registration Statement at the time of effectiveness if no
Rule 424(b) filing is required (the "Prospectus"), or any amendment or
supplement thereto, or (in the case of the Registration Statement or any
amendment thereof) arise out of or are based upon the omission or alleged
omission to state therein a material fact required to be stated therein or
necessary to make the statements therein not misleading, or (in the case of the
Prospectus and any amendment thereof or supplement thereto) arise out of or are
based upon the omission or alleged omission to state a material fact required to
be stated therein or necessary to make the statements therein, in light of the
circumstances in which they were made, not misleading, or arise out of or are
based in whole or in part on any inaccuracy in the representations and
warranties of the Company contained in this Agreement, or any failure of the
Company to perform its obligations hereunder or under law, and will reimburse
each Purchaser and each such controlling person for any legal and other expenses
reasonably incurred as such expenses are reasonably incurred by such Purchaser
or such controlling person in connection with investigating, defending,
settling, compromising or paying any such loss, claim, damage, liability,
expense or action; provided, however, that the Company will not be liable to a
Purchaser seeking indemnification in any such case to the extent that any such
loss, claim, damage, liability or expense to such Purchaser arises out of or is
based upon (i) an untrue statement or alleged untrue statement or omission or
alleged omission made in the Registration Statement, the Prospectus or any
amendment or supplement thereto in reliance upon and in conformity with written
information furnished to the Company by or on behalf of such Purchaser expressly
for use therein, or (ii) the failure of such Purchaser to comply with the
covenants and agreements contained in Sections 5(b) or 7.2 hereof respecting
sale of the Shares, or (iii) the inaccuracy of any representations made by such
Purchaser herein or (iv) any statement or omission in any Prospectus that is
corrected in any subsequent

<PAGE>

Prospectus that was delivered to the Purchaser prior to the pertinent sale or
sales by the Purchaser.

          (b)  Each Purchaser will severally indemnify and hold harmless the
Company, each of its directors, each of its officers who signed the Registration
Statement and each person, if any, who controls the Company within the meaning
of the Securities Act, against any losses, claims, damages, liabilities or
expenses to which the Company, each of its directors, each of its officers who
signed the Registration Statement or controlling person may become subject,
under the Securities Act, the Exchange Act, or any other federal or state
statutory law or regulation, or at common law or otherwise (including in
settlement of any litigation, if such settlement is effected with the written
consent of such Purchaser) insofar as such losses, claims, damages, liabilities
or expenses (or actions in respect thereof as contemplated below) arise out of
or are based upon (i) any failure by such Purchaser to comply with the covenants
and agreements contained in Sections 5(b) or 7.2 hereof respecting the sale of
the Shares or (ii) the inaccuracy of any representation made by such Purchaser
herein or (iii) any untrue or alleged untrue statement of any material fact
contained in the Registration Statement, the Prospectus, or any amendment or
supplement thereto, or (in the case of the Registration Statement or any
amendment thereof) the omission or alleged omission to state therein a material
fact required to be stated therein or necessary to make the statements therein
not misleading, or (in the case of the Prospectus and any amendment thereof or
supplement thereto) the omission or alleged omission to state a material fact
required to be stated therein or necessary to make the statements therein, in
light of the circumstances in which they were made, not misleading, in each case
to the extent, but only to the extent, that such untrue statement or alleged
untrue statement or omission or alleged omission was made in the Registration
Statement, the Prospectus, or any amendment or supplement thereto, in reliance
upon and in conformity with written information furnished to the Company by or
on behalf of such Purchaser expressly for use therein, and will reimburse the
Company, each of its directors, each of its officers who signed the Registration
Statement or controlling person for any legal and other expense reasonably
incurred, as such expenses are reasonably incurred by the Company, each of its
directors, each of its officers who signed the Registration Statement or
controlling person in connection with investigating, defending, settling,
compromising or paying any such loss, claim, damage, liability, expense or
action.

          (c)  Promptly after receipt by an indemnified party under this Section
7.3 of notice of the threat or commencement of any action, such indemnified
party will, if a claim in respect thereof is to be made against an indemnifying
party under this Section 7.3, promptly notify the indemnifying party in writing
thereof, but the omission so to notify the indemnifying party will not relieve
it from any liability which it may have to any indemnified party for
contribution or otherwise to the extent it is not prejudiced as a result of such
failure. In case any such action is brought against any indemnified party and
such indemnified party seeks or intends to seek indemnity from an indemnifying
party, the indemnifying party will be entitled to participate in, and, to the
extent that it may wish, jointly with all other indemnifying parties similarly
notified, to assume the defense thereof with counsel reasonably satisfactory to
such indemnified party; provided, however, if the defendants in any such action
include both the indemnified party and the indemnifying party and the
indemnified party shall have reasonably concluded that there may be a conflict
between the positions of the indemnifying party and the indemnified party in
conducting the defense of any such action or that there may be legal defenses
available to it and/or other indemnified parties which are different from or
additional to

<PAGE>

those available to the indemnifying party, the indemnified party or parties
shall have the right to select separate counsel to assume such legal defenses
and to otherwise participate in the defense of such action on behalf of such
indemnified party or parties. Upon receipt of notice from the indemnifying
party to such indemnified party of its election so to assume the defense of
such action and approval by the indemnified party of counsel, the
indemnifying party will not be liable to such indemnified party under this
Section 7.3 for any legal or other expenses subsequently incurred by such
indemnified party in connection with the defense thereof unless (i) the
indemnified party shall have employed such counsel in connection with the
assumption of legal defenses in accordance with the proviso to the preceding
sentence (it being understood, however, that the indemnifying party shall not
be liable for the expenses of more than one separate counsel, reasonably
satisfactory to the indemnifying party, representing the indemnified parties
who are parties to such action) or (ii) the indemnified party shall not have
employed counsel reasonably satisfactory to the indemnified party to
represent the indemnified party within a reasonable time after notice of
commencement of action, in each of which cases the reasonable fees and
expenses of counsel shall be at the expense of the indemnifying party.

          (d)  If the indemnification provided for in this Section 7.3 is
required by its terms but is for any reason held to be unavailable to or
otherwise insufficient to hold harmless an indemnified party under paragraphs
(a), (b) or (c) of this Section 7.3 in respect to any losses, claims, damages,
liabilities or expenses referred to herein, then each applicable indemnifying,
party shall contribute to the amount paid or payable by such indemnified party
as a result of any losses, claims, damages, liabilities or expenses referred to
herein (i) in such proportion as is appropriate to reflect the relative benefits
received by the Company and the Purchaser from the placement of Common Stock or
(ii) if the allocation provided by clause (i) above is not permitted by
applicable law, in such proportion as is appropriate to reflect not only the
relative benefits referred to in clause (i) above but the relative fault of the
Company and the Purchaser in connection with the statements or omissions or
inaccuracies in the representations and warranties in this Agreement which
resulted in such losses, claims, damages, liabilities or expenses, as well as
any other relevant equitable considerations. The respective relative benefits
received by the Company on the one hand and each Purchaser on the other shall be
deemed to be in the same proportion as the amount paid by such Purchaser to the
Company pursuant to this Agreement for the Shares purchased by such Purchaser
that were sold pursuant to the Registration Statement bears to the difference
(the "Difference") between the amount such Purchaser paid for the Shares that
were sold pursuant to the Registration Statement and the amount received by such
Purchaser from such sale. The relative fault of such selling Purchaser and each
Purchaser shall be determined by reference to, among other things, whether the
untrue or alleged statement of a material fact or the omission or alleged
omission to state a material fact or the inaccurate or the alleged inaccurate
representation and/or warranty relates to information supplied by the Company or
by such Purchaser and the parties' relative intent, knowledge, access to
information and opportunity to correct or prevent such statement or omission.
The amount paid or payable by a party as a result of the losses, claims,
damages, liabilities and expenses referred to above shall be deemed to include,
subject to the limitations set forth in paragraph (c) of this Section 7.3, any
legal or other fees or expenses reasonably incurred by such party in connection
with investigating or defending any action or claim. The provisions set forth in
paragraph (c) of this Section 7.3 with respect to the notice of the threat or
commencement of any threat or action shall apply if a claim for contribution is
to be made under this paragraph (d); provided, however that no additional notice
shall be required with respect to any threat or action for which notice has

<PAGE>


been given under paragraph (c) for purposes of indemnification. The Company
and each Purchaser agree that it would not be just and equitable if
contribution pursuant to this Section 7.3 were determined solely by pro rata
allocation (even if the Purchaser were treated as one entity for such
purpose) or by any other method of allocation which does not take account of
the equitable considerations referred to in this paragraph. Notwithstanding
the provisions of this Section 7.3, no Purchaser shall be required to
contribute any amount in excess of the amount by which the Difference exceeds
the amount of any damages that such Purchaser has otherwise been required to
pay by reason of such untrue or alleged untrue statement or omission or
alleged omission. No person guilty of fraudulent misrepresentation (within
the meaning of Section 11(f) of the Securities Act) shall be entitled to
contribution from any person who was not guilty of such fraudulent
misrepresentation. The Purchasers' obligations to contribute pursuant to this
Section 7.3 are several and not joint.

     7.4  TERMINATION OF CONDITIONS AND OBLIGATIONS.  The conditions precedent
imposed by Section 5(b) or Section 7.2 upon the transferability of the Shares
shall cease and terminate as to any particular number of the Shares upon the
earlier of the passage of twenty-four months from the effective date of the
Registration Statement covering such Shares or such time as an opinion of
counsel satisfactory in form and substance to the Company shall have been
rendered to the effect that such conditions are not necessary in order to comply
with the Securities Act.

SECTION 8.     BROKER'S FEE.  Except as otherwise agreed to between the
Purchaser and the Placement Agent, the Purchaser acknowledges that the Company
intends to pay to the Placement Agent a fee in respect of the sale of the Shares
to the Purchaser. Each of the parties hereto hereby represents that, on the
basis of any actions and agreements by it, there are no other brokers or finders
entitled to compensation in connection with the sale of the Shares to the
Purchaser.

SECTION 9.     NOTICES.  All notices, requests, consents and other
communications hereunder shall be in writing, shall be mailed by first-class
registered or certified airmail, confirmed facsimile or nationally recognized
overnight express courier postage prepaid, and shall be deemed given when so
delivered as addressed as follows:

          (a)  if to the Company, to:

               Collateral Therapeutics, Inc.
               11622 El Camino Real
               San Diego, California 92130
               Attn: Tyler M. Dylan, Esq.
               Fax: (858) 794-3440

               with a copy to:

               Brobeck, Phleger & Harrison LLP
               550 West C Street
               Suite 1300
               San Diego, California  92101
               Attn:  Faye H. Russell, Esq.
               Fax: (619) 234-3848

<PAGE>

or to such other person at such other place as the Company shall designate to
the Purchaser in writing; and

          (b)  if to the Purchaser, at its address as set forth at the end of
this Agreement, or at such other address or addresses as may have been furnished
to the Company in writing.

SECTION 10.    CHANGES.  This Agreement may not be modified or amended except
pursuant to an instrument in writing, signed by the Company and the Purchaser.

SECTION 11.    HEADINGS.  The headings of the various sections of this Agreement
have been inserted for convenience of reference only and shall not be deemed to
be part of this Agreement.

SECTION 12.    SEVERABILITY.  In case any provision contained in this Agreement
should be invalid, illegal or unenforceable in any respect, the validity,
legality and enforceability of the remaining provisions contained herein shall
not in any way be affected or impaired thereby.

SECTION 13.    GOVERNING LAW.  This Agreement shall be governed by and construed
in accordance with the laws of the State of New York, without giving effect to
any choice of law provisions thereof, and the federal law of the United States
of America.

SECTION 14.    COUNTERPARTS.  This Agreement may be executed in two or more
counterparts, each of which shall constitute an original, but all of which, when
taken together, shall constitute but one instrument, and shall become effective
when one or more counterparts have been signed by each party hereto and
delivered to the other parties.


                           [REMAINDER OF THIS PAGE BLANK]

<PAGE>

IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be executed
by their duly-authorized representatives shown below.

    PURCHASER*


<TABLE>
<CAPTION>

                                                                    Number of
 Name of Purchaser                                                   Shares
--------------------------------------------------------------------------------
<S>                                                                 <C>
 1.   Franklin Biotechnology Discovery Fund (#402)                        63,000
 2.   Franklin California Growth Fund (#180)                             125,000
 3.   Franklin Small Cap Fund (#198)                                     312,000
 4.   Heritage Series Trust Aggressive Growth                             30,000
 5.   Heritage Series Trust Smallcap Stock Fund                           60,000
 6.   Howard J. Leonhardt                                                 60,000
 7.   Invesco Funds Group, Inc.                                          200,000
 8.   Jackson National Life Eagle Smallcap Equity Series                  60,000
 9.   Moore Global Investments Ltd.                                      109,500
 10.  Nordbanken Fonder AB                                                40,000
 11.  Remington Investments Strategies, L.P.                              24,000
 12.  SEB Fondforvaltning                                                 85,000
 13.  SEB Private Bank Luxemburg                                          15,000
 14.  SL Holdings Ltd.                                                    16,500
 15.  State of Wisconsin Investment Board                                750,000
 16.  T. Rowe Price New Horizons Fund, Inc.                              200,000

</TABLE>

Accepted and Agreed to by:

                                   COLLATERAL THERAPEUTICS, INC.
                                   /s/  Jack W. Reich, Ph.D.
                                   ------------------------------
                                   Jack W. Reich, Ph.D.
                                   President and Chief Executive Officer

                                   Date: August 11, 1999

---------------------------
*Separate Purchase Agreements were executed on behalf of each named Purchaser.