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                                                                   EXHIBIT 10.48

                         COLLATERAL THERAPEUTICS, INC.
               STOCK OPTION AGREEMENT FOR NON-EMPLOYEE DIRECTORS


RECITALS

         I. The Corporation has implemented an automatic option grant program
under the Plan pursuant to which eligible non-employee members of the Board will
automatically receive special option grants at periodic intervals over their
period of Board service in order to provide such individuals with a meaningful
incentive to continue to serve as members of the Board.

         A. Optionee is an eligible non-employee Board member, and this
Agreement is executed pursuant to, and is intended to carry out the purposes of,
the Plan in connection with the automatic grant of an option to purchase shares
of Common Stock under the Plan.

         B. All capitalized terms in this Agreement shall have the meaning
assigned to them in the attached Appendix.

         NOW, THEREFORE, it is hereby agreed as follows:

         1. GRANT OF OPTION. The Corporation hereby grants to Optionee, as of
the Grant Date, a Non-Statutory Option to purchase up to the number of Option
Shares specified in the Grant Notice. The Option Shares shall be purchasable
from time to time during the option term specified in Paragraph 2 at the
Exercise Price.

         2. OPTION TERM. This option shall have a term of ten (10) years
measured from the Grant Date and shall accordingly expire at the close of
business on the Expiration Date, unless sooner terminated in accordance with
Paragraph 5, 6 or 7.

         3. LIMITED TRANSFERABILITY. This option may, in connection with the
Optionee's estate plan, be assigned in whole or in part during Optionee's
lifetime to one or more members of the Optionee's immediate family or to a trust
established for the exclusive benefit of the Optionee and/or one or more such
family members. The assigned portion shall be exercisable only by the person or
persons who acquire a proprietary interest in the option pursuant to such
assignment. The terms applicable to the assigned portion shall be the same as
those in effect for this option immediately prior to such assignment. Should the
Optionee die while holding this option, then this option shall be transferred in
accordance with Optionee's will or the laws of descent and distribution.


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         4. EXERCISABILITY/VESTING.

            (a) This option shall be immediately exercisable for any or all of
the Option Shares, whether or not the Option Shares are at the time vested in
accordance with the Vesting Schedule, and shall remain so exercisable until the
Expiration Date or sooner termination of the option term under Paragraph 5, 6 or
7.

            (b) Optionee shall, in accordance with the Vesting Schedule set
forth in the Grant Notice, vest in the Option Shares in one or more installments
over his or her period of Board service. Vesting in the Option Shares may be
accelerated pursuant to the provisions of Paragraph 5, 6 or 7. In no event,
however, shall any additional Option Shares vest following Optionee's cessation
of service as a Board member.

         5. CESSATION OF BOARD SERVICE. Should Optionee's service as a Board
member cease while this option remains outstanding, then the option term
specified in Paragraph 2 shall terminate (and this option shall cease to be
outstanding) prior to the Expiration Date in accordance with the following
provisions:

            (a) Should Optionee cease to serve as a Board member for any reason
(other than death or Permanent Disability) while this option is outstanding,
then the period for exercising this option shall be reduced to a twelve
(12)-month period (commencing with the date of such cessation of Board service),
but in no event shall this option be exercisable at any time after the
Expiration Date. During such limited period of exercisability, this option may
not be exercised in the aggregate for more than the number of Option Shares (if
any) in which Optionee is vested on the date of his or her cessation of Board
service. Upon the EARLIER of (i) the expiration of such twelve (12)-month period
or (ii) the specified Expiration Date, the option shall terminate and cease to
be exercisable with respect to any vested Option Shares for which the option has
not been exercised.

            (b) Should Optionee die within the twelve (12)-month period
following his or her cessation of Board service and hold this option at the time
of his or her death, then the personal representative of Optionee's estate or
the person or persons to whom the option is transferred pursuant to Optionee's
will or in accordance with the laws of descent and distribution shall have the
right to exercise this option for any or all of the Option Shares in which
Optionee is vested at the time of Optionee's cessation of Board service (less
any Option Shares purchased by Optionee after such cessation of Board service
but prior to death). Such right of exercise shall terminate, and this option
shall accordingly cease to be exercisable for such vested Option Shares, upon
the EARLIER of (i) the expiration of the twelve (12)-month period measured from
the date of Optionee's cessation of Board service or (ii) the specified
Expiration Date.

            (c) Should Optionee cease service as a Board member by reason of
death or Permanent Disability, then all Option Shares at the time subject to
this option but not otherwise vested shall vest in full so that this option may
be exercised for any or all of the Option Shares as fully vested shares of
Common Stock at any time prior to the EARLIER of (i) the expiration of the
twelve (12)-month period measured from the date of Optionee's cessation of


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Board service or (ii) the specified Expiration Date, whereupon this option shall
terminate and cease to be outstanding.

            (d) Upon Optionee's cessation of Board service for any reason other
than death or Permanent Disability, this option shall immediately terminate and
cease to be outstanding with respect to any and all Option Shares in which
Optionee is not otherwise at that time vested in accordance with the normal
Vesting Schedule or the special vesting acceleration provisions of Paragraph 6
or 7 below.

         6. CHANGE IN CONTROL.

            (a) In the event of a Change in Control transaction, all Option
Shares at the time subject to this option but not otherwise vested shall
automatically vest so that this option shall, immediately prior to the specified
effective date for the Change in Control, become exercisable for all of those
Option Shares as fully-vested shares of Common Stock and may be exercised for
all or any portion of those vested shares. Immediately following the
consummation of the Change in Control, this option shall terminate and cease to
be outstanding, except to the extent assumed by the successor corporation or its
parent company or otherwise continued in full force and effect pursuant to the
terms of the Change in Control transaction.

            (b) If this option is assumed in connection with a Change in Control
(or otherwise continued in full force and effect), then this option shall be
appropriately adjusted, immediately after such Change in Control, to apply to
the number and class of securities or other property which would have been
issuable to Optionee in consummation of such Change in Control had the option
been exercised immediately prior to such Change in Control, and appropriate
adjustments shall also be made to the Exercise Price, PROVIDED the aggregate
Exercise Price shall remain the same.

         7. HOSTILE TAKE-OVER.

            (a) Optionee shall have an unconditional right, exercisable at the
time during the thirty (30)-day period immediately following the consummation of
a Hostile Take-Over, to surrender this option to the Corporation in exchange for
a cash distribution from the Corporation in an amount equal to the excess of (i)
the Take-Over Price of the Option Shares at the time subject to the surrendered
option (whether or not those Option Shares are otherwise at the time vested)
over (ii) the aggregate Exercise Price payable for such shares. This Paragraph
7(a) limited stock appreciation right shall in all events terminate upon the
expiration or sooner termination of the option term and may not be assigned or
transferred by Optionee.

            (b) To exercise the Paragraph 7(a) limited stock appreciation right,
Optionee must, during the applicable thirty (30)-day exercise period, provide
the Corporation with written notice of the option surrender in which there is
specified the number of Option Shares as to which the option is being
surrendered. Such notice must be accompanied by the return of Optionee's copy of
this Agreement, together with any written amendments to such Agreement. The cash
distribution shall be paid to Optionee within five (5) business days following
such delivery date. The exercise of such limited stock appreciation right in
accordance with the terms of this Paragraph 7 has been pre-approved pursuant to
the express provisions of


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the Automatic Option Grant Program, and neither the approval of the Plan
Administrator nor the consent of the Board shall be required at the time of the
actual option surrender and cash distribution. Upon receipt of the cash
distribution, this option shall be cancelled with respect to the shares subject
to the surrendered option (or the surrendered portion), and Optionee shall cease
to have any further right to acquire those Option Shares under this Agreement.
The option shall, however, remain outstanding for the balance of the Option
Shares (if any) in accordance with the terms and provisions of this Agreement,
and the Corporation shall accordingly issue a replacement stock option agreement
(substantially in the same form as this Agreement) for those remaining Option
Shares.

         8. ADJUSTMENT IN OPTION SHARES. Should any change be made to the Common
Stock by reason of any stock split, stock dividend, recapitalization,
combination of shares, exchange of shares or other change affecting the
outstanding Common Stock as a class without the Corporation's receipt of
consideration, appropriate adjustments shall be made to (i) the total number
and/or class of securities subject to this option and (ii) the Exercise Price in
order to reflect such change and thereby preclude a dilution or enlargement of
benefits hereunder.

         9. STOCKHOLDER RIGHTS. The holder of this option shall not have any
stockholder rights with respect to the Option Shares until such person shall
have exercised the option, paid the Exercise Price and become a holder of record
of the purchased shares.

         10. MANNER OF EXERCISING OPTION.

            (a) In order to exercise this option with respect to all or any part
of the Option Shares for which this option is at the time exercisable, Optionee
(or any other person or persons exercising the option) must take the following
actions:

                  (i) To the extent the option is exercised for vested Option
         Shares, execute and deliver to the Corporation a Notice of Exercise for
         the Option Shares for which the option is exercised. To the extent this
         option is exercised for unvested Option Shares, execute and deliver to
         the Corporation a Purchase Agreement for those unvested Option Shares.

                  (ii) Pay the aggregate Exercise Price for the purchased shares
         in one or more of the following forms:

                           (A) cash or check made payable to the Corporation,

                           (B) shares of Common Stock held by Optionee (or any
                  other person or persons exercising the option) for the
                  requisite period necessary to avoid a charge to the
                  Corporation's earnings for financial reporting purposes and
                  valued at Fair Market Value on the Exercise Date, or

                           (C) to the extent the option is exercised for vested
                  Option Shares, through a special sale and remittance procedure


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                  pursuant to which Optionee (or any other person or persons
                  exercising the option) shall concurrently provide irrevocable
                  instructions (I) to a Corporation-designated brokerage firm to
                  effect the immediate sale of the purchased shares and remit to
                  the Corporation, out of the sale proceeds available on the
                  settlement date, sufficient funds to cover the aggregate
                  Exercise Price payable for the purchased shares plus all
                  applicable Federal, state and local income and employment
                  taxes required to be withheld by the Corporation by reason of
                  such exercise and (II) to the Corporation to deliver the
                  certificates for the purchased shares directly to such
                  brokerage firm in order to complete the sale.

                  (iii) Furnish to the Corporation appropriate documentation
         that the person or persons exercising the option (if other than
         Optionee) have the right to exercise this option.

            (b) Except to the extent the sale and remittance procedure is
utilized in connection with the option exercise, payment of the Exercise Price
must accompany the Notice of Exercise (or the Purchase Agreement) delivered to
the Corporation in connection with the option exercise.

            (c) As soon after the Exercise Date as practical, the Corporation
shall issue to or on behalf of Optionee (or any other person or persons
exercising this option) a certificate for the purchased Option Shares, with the
appropriate legends affixed thereto. To the extent any such Option Shares are
unvested, the certificates for those Option Shares shall be endorsed with an
appropriate legend evidencing the Corporation's repurchase rights and may be
held in escrow with the Corporation until such shares vest.

            (d) In no event may this option be exercised for any fractional
shares.

         11. NO IMPAIRMENT OF RIGHTS. This Agreement shall not in any way affect
the right of the Corporation to adjust, reclassify, reorganize or otherwise make
changes in its capital or business structure or to merge, consolidate, dissolve,
liquidate or sell or transfer all or any part of its business or assets. In
addition, this Agreement shall not in any way be construed or interpreted so as
to affect adversely or otherwise impair the right of the Corporation or the
stockholders to remove Optionee from the Board at any time in accordance with
the provisions of applicable law.

         12. COMPLIANCE WITH LAWS AND REGULATIONS.

            (a) The exercise of this option and the issuance of the Option
Shares upon such exercise shall be subject to compliance by the Corporation and
Optionee with all applicable requirements of law relating thereto and with all
applicable regulations of any stock exchange (or the Nasdaq National Market, if
applicable) on which the Common Stock may be listed for trading at the time of
such exercise and issuance.

            (b) The inability of the Corporation to obtain approval from any
regulatory body having authority deemed by the Corporation to be necessary to
the lawful issuance and sale of any Common Stock pursuant to this option shall
relieve the Corporation of


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any liability with respect to the non-issuance or sale of the Common Stock as to
which such approval shall not have been obtained. The Corporation, however,
shall use its best efforts to obtain all such approvals.

         13. SUCCESSORS AND ASSIGNS. Except to the extent otherwise provided in
Paragraph 3 or 6, the provisions of this Agreement shall inure to the benefit
of, and be binding upon, the Corporation and its successors and assigns and
Optionee, Optionee's assigns and the legal representatives, heirs and legatees
of Optionee's estate.

         14. NOTICES. Any notice required to be given or delivered to the
Corporation under the terms of this Agreement shall be in writing and addressed
to the Corporation at its principal corporate offices. Any notice required to be
given or delivered to Optionee shall be in writing and addressed to Optionee at
the address indicated below Optionee's signature line on the Grant Notice. All
notices shall be deemed effective upon personal delivery or upon deposit in the
U.S. mail, postage prepaid and properly addressed to the party to be notified.

         15. CONSTRUCTION. This Agreement and the option evidenced hereby are
made and granted pursuant to the Plan and are in all respects limited by and
subject to the terms of the Plan.

         16. GOVERNING LAW. The interpretation, performance and enforcement of
this Agreement shall be governed by the laws of the State of California without
resort to that State's conflict-of-laws rules.


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                                   EXHIBIT I

                               NOTICE OF EXERCISE

         I hereby notify Collateral Therapeutics, Inc. (the "Corporation")
that I elect to purchase "___" shares of the Corporation's Common Stock (the
"Purchased Shares") at the option exercise price of $ "___" per share (the
"Exercise Price") pursuant to that certain option (the "Option") granted to
me under the Corporation's 1998 Stock Incentive Plan on "_______" , 19__ .

         Concurrently with the delivery of this Exercise Notice to the
Corporation, I shall hereby pay to the Corporation the Exercise Price for the
Purchased Shares in accordance with the provisions of my agreement with the
Corporation (or other documents) evidencing the Option and shall deliver
whatever additional documents may be required by such agreement as a condition
for exercise. Alternatively, I may utilize the special broker-dealer sale and
remittance procedure specified in my agreement to effect payment of the Exercise
Price for any Purchased Shares in which I am vested at the time of exercise of
the Option.


_________, 20___.
Date


                                        ---------------------------------------
                                        Optionee

                                        Address:
                                                -------------------------------

                                        ---------------------------------------

Print name in exact manner
it is to appear on the
stock certificate:
                                        ---------------------------------------



Address to which certificate
is to be sent, if different
from address above:
                                        ---------------------------------------

                                        ---------------------------------------

Social Security Number:                 ---------------------------------------


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                                    APPENDIX


         The following definitions shall be in effect under the Agreement:

         A. AGREEMENT shall mean this Automatic Stock Option Agreement.

         B. BOARD shall mean the Corporation's Board of Directors.

         C. CHANGE IN CONTROL shall mean a change in ownership or control of the
Corporation effected through any of the following transactions:

                  (i) a merger or consolidation in which securities possessing
         more than fifty percent (50%) of the total combined voting power of the
         Corporation's outstanding securities are transferred to a person or
         persons different from the persons holding those securities immediately
         prior to such transaction, or

                  (ii) the sale, transfer or other disposition of all or
         substantially all of the Corporation's assets in complete liquidation
         or dissolution of the Corporation, or

                  (iii) the acquisition, directly or indirectly, by any person
         or related group of persons (other than the Corporation or a person
         that directly or indirectly controls, is controlled by, or is under
         common control with, the Corporation) of beneficial ownership (within
         the meaning of Rule 13d-3 of the 1934 Act) of securities possessing
         more than fifty percent (50%) of the total combined voting power of the
         Corporation's outstanding securities pursuant to a tender or exchange
         offer made directly to the Corporation's stockholders, or

                  (iv) a change in the composition of the Board over a period of
         thirty-six (36) consecutive months or less such that a majority of the
         Board members ceases, by reason of one or more contested elections for
         Board membership, to be comprised of individuals who either (A) have
         been Board members continuously since the beginning of such period or
         (B) have been elected or nominated for election as Board members during
         such period by at least a majority of the Board members described in
         clause (A) who were still in office at the time the Board approved such
         election or nomination.

         D. COMMON STOCK shall mean shares of the Corporation's common stock.

         E. CODE shall mean the Internal Revenue Code of 1986, as amended.

         F. CORPORATION shall mean Collateral Therapeutics, Inc., a Delaware
corporation.


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         G. EXERCISE DATE shall mean the date on which the option shall have
been exercised in accordance with Paragraph 10 of the Agreement.

         H. EXERCISE PRICE shall mean the exercise price per share as specified
in the Grant Notice.

         I. EXPIRATION DATE shall mean the date on which the option expires
as specified in the Grant Notice.

         J. FAIR MARKET VALUE per share of Common Stock on any relevant date
shall be determined in accordance with the following provisions:

                  (i) If the Common Stock is at the time traded on the Nasdaq
         National Market, then the Fair Market Value shall be the closing
         selling price per share of Common Stock on the date in question, as the
         price is reported by the National Association of Securities Dealers on
         the Nasdaq National Market. If there is no closing selling price for
         the Common Stock on the date in question, then the Fair Market Value
         shall be the closing selling price on the last preceding date for which
         such quotation exists.

                  (ii) If the Common Stock is at the time listed on any Stock
         Exchange, then the Fair Market Value shall be the closing selling price
         per share of Common Stock on the date in question on the Stock Exchange
         which serves as the primary market for the Common Stock, as such price
         is officially quoted in the composite tape of transactions on such
         exchange. If there is no closing selling price for the Common Stock on
         the date in question, then the Fair Market Value shall be the closing
         selling price on the last preceding date for which such quotation
         exists.

         K. GRANT DATE shall mean the date of grant of the option as specified
in the Grant Notice.

         L. GRANT NOTICE shall mean the Notice of Grant of Automatic Stock
Option accompanying the Agreement, pursuant to which Optionee has been informed
of the basic terms of the option evidenced hereby.

         M. HOSTILE TAKEOVER shall mean the acquisition, directly or indirectly,
by any person or related group of persons (other than the Corporation or a
person that directly or indirectly controls, is controlled by, or is under
common control with, the Corporation) of beneficial ownership (within the
meaning of Rule 13d-3 of the 1934 Act) of securities possessing more than fifty
percent (50%) of the total combined voting power of the Corporation's
outstanding securities pursuant to a tender or exchange offer made directly to
the Corporation's stockholders which the Board does not recommend such
stockholders to accept.


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         N. 1934 ACT shall mean the Securities Exchange Act of 1934, as amended.

         O. NON-STATUTORY OPTION shall mean an option not intended to satisfy
the requirements of Code Section 422.

         P. NOTICE OF EXERCISE shall mean the notice of exercise in the form of
Exhibit I.

         Q. OPTION SHARES shall mean the number of shares of Common Stock
subject to the option.

         R. OPTIONEE shall mean the person to whom the option is granted as
specified in the Grant Notice.

         S. PERMANENT DISABILITY shall mean the inability of Optionee to perform
his or her usual duties as a member of the Board by reason of any medically
determinable physical or mental impairment which is expected to result in death
or has lasted or can be expected to last for a continuous period of twelve (12)
months or more.

         T. PLAN shall mean the Corporation's 1998 Stock Incentive Plan.

         U. PURCHASE AGREEMENT shall mean the stock purchase agreement (in form
and substance satisfactory to the Corporation) which grants the Corporation the
right to repurchase, at the Exercise Price, any and all unvested Option Shares
held by Optionee at the time of Optionee's cessation of Board service and which
precludes the sale, transfer or other disposition of any purchased Option Shares
while those shares are unvested and subject to such repurchase right.

         V. STOCK EXCHANGE shall mean the American Stock Exchange or the New
York Stock Exchange.

         W. TAKE-OVER PRICE shall mean the GREATER of (i) the Fair Market Value
per share of Common Stock on the date the option is surrendered to the
Corporation in connection with a Hostile Take-Over or (ii) the highest reported
price per share of Common Stock paid by the tender offeror in effecting the
Hostile Take-Over.


         X. VESTING SCHEDULE shall mean the vesting schedule specified in the
Grant Notice, pursuant to which the Option Shares will vest in one or more
installments over the Optionee's period of Board service, subject to
acceleration in accordance with the provisions of the Agreement.