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                                                               EXHIBIT 10.43

                               CORTECH, INC.
                        1993 EQUITY INCENTIVE PLAN
                         Adopted December 10, 1993
                 Approved by the Stockholders May 10, 1994


1.  PURPOSES

   (a) The purpose of the 1993 Equity Incentive Plan (the "Plan") is to
provide a means by which employees of and consultants to the Company, and its
Affiliates, may be given an opportunity to benefit from increases in value of
the stock of the Company through the granting of (i) Incentive Stock Options,
(ii) Nonstatutory Stock Options, (iii) stock bonuses, (iv) rights to purchase
restricted stock, and (v) stock appreciation rights, all as defined below.

   (b) The Company, by means of the Plan, seeks to retain the services of
persons who are now Employees or Directors of or Consultants to the Company,
to secure and retain the services of new Employees, Directors and
Consultants, and to provide incentives for such persons to exert maximum
efforts for the success of the Company.

   (c) The Company intends that the Stock Awards issued under the Plan
shall, in the discretion of the Board or any Committee to which
responsibility for administration of the Plan has been delegated pursuant to
subsection 3(c), be either (i) Options granted pursuant to paragraph 6
hereof, including Incentive Stock Options and Nonstatutory Stock Options,
(ii) stock bonuses or rights to purchase restricted stock granted pursuant to
paragraph 7 hereof, or (iii) stock appreciation rights granted pursuant to
paragraph 8 hereof.  All Options shall be separately designated Incentive
Stock Options or Nonstatutory Stock Options at the time of grant, and in such
form as issued pursuant to section 6, and a separate certificate or
certificates will be issued for shares purchased on exercise of each type of
Option.

2.  DEFINITIONS

   (a) "AFFILIATE" means any parent corporation or subsidiary corporation,
whether now or hereafter existing, as those terms are defined in Sections
424(e) and (f) respectively, of the Code.

   (b) "BOARD" means the Board of Directors of the Company.

   (c) "CODE" means the Internal Revenue Code of 1986, as amended.

   (d) "COMMITTEE" means a Committee appointed by the Board in accordance
with subsection 3(c) of the Plan.

   (e) "COMPANY" means Cortech, Inc., a Delaware corporation.

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   (f) "CONCURRENT STOCK APPRECIATION RIGHT" or "CONCURRENT RIGHT" means a
right granted pursuant to subsection 8(b)(ii) of the Plan.

   (g) "CONSULTANT" means any person, including an advisor, engaged by the
Company or an Affiliate to render services and who is compensated for such
services, provided that the term "Consultant" shall not include Directors who
are paid only a director's fee by the Company or who are not compensated by
the Company for their services as Directors.

   (h) "CONTINUOUS STATUS AS AN EMPLOYEE, DIRECTOR OR CONSULTANT" means the
employment or relationship as a Director or Consultant is not interrupted or
terminated by the Company or any Affiliate.  The Board, in its sole
discretion, may determine whether Continuous Status as an Employee, Director
or Consultant shall be considered interrupted in the case of: (i) any leave of
absence approved by the Board, including sick leave, military leave, or any
other personal leave; provided, however, that for purposes of Incentive Stock
Options and Stock Appreciation Rights appurtenant thereto, any such leave may
not exceed ninety (90) days, unless reemployment upon the expiration of such
leave is guaranteed by contract (including certain Company policies) or
statute; or (ii) transfers between locations of the Company or between the
Company, Affiliates or its successor.

   (i) "COVERED EXECUTIVE" means each Officer of the Company.

   (j) "DIRECTOR" means a member of the Board.

   (k) "DISABILITY" means total and permanent disability as defined in
Section 22(e)(3) of the Code.

   (l) "DISINTERESTED PERSON" means a Director: (i) who was either (A) not
during the one year prior to service as an administrator of the Plan granted
or awarded equity securities pursuant to the Plan or any other plan of the
Company or any of its affiliates entitling the participants therein to acquire
equity securities of the Company or any of its affiliates except as permitted
by Rule 16b-3(c)(2)(i) or (B) who is otherwise considered to be a
"disinterested person" in accordance with Rule 16b-3(c)(2)(i), or any other
applicable rules, regulations or interpretations of the Securities and
Exchange Commission; and (ii) who either (A) is not a current Employee, is
not a former Employee receiving compensation for prior services (other than
benefits under a tax qualified pension plan), was not an officer of the
Company or an Affiliate at any time, and is not currently receiving
compensation for personal services in any capacity other than as a Director,
or (B) is otherwise considered an outside director for purposes of Section
162(m) of the Code.

   (m) "EMPLOYEE" means any person, including Officers and Directors,
employed by the Company or any Affiliate of the Company.  Neither service as
a Director nor payment of a director's fee by the Company shall be sufficient
to constitute "employment" by the Company.

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   (n) "EXCHANGE ACT" means the Securities Exchange Act of 1934, as amended.

   (o) "FAIR MARKET VALUE" means, as of any date, the value of the common
stock of the Company determined as follows:

         (i) If the common stock is listed on any established stock
exchange or a national market system, including without limitation the
National Market System of the National Association of Securities Dealers,
Inc. Automated Quotation ("NASDAQ") System, the Fair Market Value of a share
of common stock shall be the closing sales price for such stock (or the
closing bid, if no sales were reported) as quoted on such system or exchange
(or the exchange with the greatest volume of trading in common stock) on the
last market trading day prior to the day of determination, as reporting in
the Wall Street Journal or such other source as the Board deems reliable;

         (ii) If the common stock is quoted on the NASDAQ System (but not on
the National Market System thereof) or is regularly quoted by a recognized
securities dealer but selling prices are not reported, the Fair Market Value
of a share of common stock shall be the mean between the bid and asked prices
for the common stock on the last market trading day prior to the day of
determination, as reported in the Wall Street Journal or such other source as
the Board deems reliable;

         (iii) In the absence of an established market for the common stock,
the Fair Market Value shall be determined in good faith by the Board.

   (p) "INCENTIVE STOCK OPTION" means an Option intended to qualify as an
incentive stock option within the meaning of Section 422 of the Code and the
regulations promulgated thereunder.

   (q) "INDEPENDENT STOCK APPRECIATION RIGHT" or "INDEPENDENT RIGHT" means
a right granted under subsection 8(b)(iii) of the Plan.

   (r) "NONSTATUTORY STOCK OPTION" means an Option not intended to qualify
as an Incentive Stock Option.

   (s) "OFFICER" means a person who is an officer of the Company within the
meaning of Section 16 of the Exchange Act and the rules and regulations
promulgated thereunder.

   (t) "OPTION" means a stock option granted pursuant to the Plan.

   (u) "OPTION AGREEMENT" means a written agreement between the Company and
an Optionee evidencing the terms and conditions of an individual Option
grant.  The Option Agreement is subject to the terms and conditions of the
Plan.

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   (v) "OPTIONEE" means an Employee, Director or Consultant who holds an
outstanding Option.

   (w) "PLAN" means this 1993 Equity Incentive Plan.

   (x) "RULE 16b-3" means Rule 16b-3 of the Exchange Act or any successor
to Rule 16b-3, as in effect when discretion is being exercised with respect
to the Plan.

   (y) "STOCK APPRECIATION RIGHT" means any of the various types of rights
which may be granted under Section 8 of the Plan.

   (z) "STOCK AWARD" means any right granted under the Plan, including any
Option, any stock bonus, any right to purchase restricted stock, and any
Stock Appreciation Right.

   (aa) "STOCK AWARD AGREEMENT" means a written agreement between the
Company and a holder of a Stock Award evidencing the terms and conditions of
an individual Stock Award grant.  The Stock Award Agreement is subject to the
terms and conditions of the Plan.

   (ab) "TANDEM STOCK APPRECIATION RIGHT" or "TANDEM RIGHT" means a right
granted under subsection 8(b)(i) of the Plan.

3.  ADMINISTRATION

   (a) The Plan shall be administered by the Board unless and until the
Board delegates administration to a Committee, as provided in subsection
3(c).

   (b) The Board shall have the power, subject to, and within the
limitations of, the express provisions of the Plan:

         (1) To determine from time to time which of the persons eligible
under the Plan shall be granted Stock Awards, when and how Stock Awards shall
be granted; whether a Stock Award will be an Incentive Stock Option, a
Nonstatutory Stock Option, a stock bonus, a right to purchase restricted
stock, a stock appreciation right, or a combination of the foregoing: the
provisions of each Stock Award granted (which need not be identical),
including the time or times when a person shall be permitted to receive
stock pursuant to a Stock Award; whether a person shall be permitted to
receive stock upon exercise of an Independent Stock Appreciation Right; and
the number of shares with respect to which Stock Awards shall be granted to
each such person.

         (2) To construe and interpret the Plan and Stock Awards granted
under it, and to establish, amend and revoke rules and regulations for its
administration.  The Board, in the exercise of this power, may correct any
defect, omission or inconsistency in the Plan or in any Stock Award
Agreement, in a manner and to the extent it shall deem necessary or expedient
to make the Plan fully effective.

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         (3) To amend the Plan as provided in Section 14.

         (4) Generally, to exercise such powers and to perform such acts as
the Board deems necessary or expedient to promote the best interests of the
Company.

   (c) The Board may delegate administration of the Plan to a committee
composed of not fewer than two (2) members (the "Committee"), all of the
members of which Committee shall be disinterested persons, if required and as
defined by the provisions of subsection 3(d).  If administration is delegated
to a Committee, the Committee shall have, in connection with the
administration of the Plan, the powers theretofore possessed by the Board
(and references in this Plan to the Board shall thereafter be to the
Committee), subject, however, to such resolutions, not inconsistent with the
provisions of the Plan, as may be adopted from time to time by the Board.
The Board may abolish the Committee at any time and revest in the Board the
administration of the Plan.  Notwithstanding anything in this Section 3 to
the contrary, the Board or the Committee may delegate to a committee of one
or more members of the Board the authority to grant options to eligible
persons who are not then subject to Section 16 of the Securities Exchange Act
of 1934, as amended (the "Exchange Act").

   (d) Any requirement that an administrator of the Plan be a Disinterested
Person shall not apply if the Board or the Committee expressly declares that
such requirement shall not apply.  Any Disinterested Person shall otherwise
comply with the requirements of Rule 16b-3.

4.  SHARES SUBJECT TO THE PLAN

   (a) Subject to the provisions of Section 13 relating to adjustments
upon changes in stock, the stock that may be issued pursuant to Stock Awards
shall not exceed in the aggregate one million seven hundred thousand
(1,700,000) shares of the Company's common stock.  If any Stock Award shall
for any reason expire or otherwise terminate without having been exercised in
full, the stock not purchased under such Stock Award shall again become
available for the Plan.  Shares subject to Stock Appreciation Rights
exercised in accordance with Section 8 of the Plan shall not be available for
subsequent issuance under the Plan.

   (b) The stock subject to the Plan may be unissued shares or reacquired
shares, bought on the market or otherwise.

5.  ELIGIBILITY

   (a) Incentive Stock Options and Stock Appreciation Rights appurtenant
thereto may be granted only to Employees.  Stock Awards other than Incentive
Stock Options and Stock Appreciation Rights appurtenant thereto may be
granted only to Employees, Directors or Consultants.

   (b) A Director shall in no event be eligible for the benefits of the
Plan unless at the time discretion is exercised in the selection of the
Director as a person to whom Stock

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Awards may be granted, or in the determination of the number of shares which
may be covered by Stock Awards granted to the Director: (i) the Board has
delegated its discretionary authority over the Plan to a Committee which
consists solely of Disinterested Persons; or (ii) the Plan otherwise
complies with the requirements of Rule 16b-3.  This subsection 5(b) shall
not apply if the Board or Committee expressly declares that it shall not
apply.

   (c) No person shall be eligible for the grant of an Incentive Stock
Option if, at the time of grant, such person owns (or is deemed to own
pursuant to Section 424(d) of the Code) stock possessing more than ten
percent (10%) of the total combined voting power of all classes of stock of
the Company or of any of its Affiliates unless the exercise price of such
Incentive Stock Option is at least one hundred ten percent (110%) of the Fair
Market Value of such stock at the date of grant and the Incentive Stock Option
is not exercisable after the expiration of five (5) years from the date of
grant.

   (d) No Employee shall be eligible to be granted Options and Stock
Appreciation Rights covering more than two hundred fifty thousand (250,000)
shares of the Company's common stock in any twelve (12) month period.

6. OPTION PROVISIONS

   Each Option shall be in such form and shall contain such terms and
conditions as the Board shall deem appropriate.  The provisions of separate
Options need not be identical, but each Option shall include (through
incorporation of provisions hereof by reference in the Option or otherwise)
the substance of each of the following provisions:

   (a) TERM.  No Option shall be exercisable after the expiration of ten
(10) years from the date it was granted.

   (b) PRICE.  The exercise price of each Incentive Stock Option shall be
not less than one hundred percent (100%) of the fair market value of the
stock subject to the Option on the date the Option is granted.  The exercise
price of each Nonstatutory Stock Option shall be not less than eighty-five
percent (85%) of the fair market value of the stock subject to the Option on
the date the Option is granted.

   (c) CONSIDERATION.  The purchase price of stock acquired pursuant to an
Option shall be paid, to the extend permitted by applicable statutes and
regulations, either (i) in cash at the time the option is exercised, or (ii)
at the discretion of the Board or the Committee, either at the time of the
grant or exercise of the Option, (A) by delivery to the Company of other
common stock of the Company, (B) according to a deferred payment or other
arrangement (which may include, without limiting the generality of the
foregoing, the use of other common stock of the Company) with the person to
whom the Option is granted or to whom the Option is transferred pursuant to
subsection 6(d) or (C) in any other form of legal consideration that may be
acceptable to the Board.

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In the case of any deferred payment arrangement, interest shall be payable at
least annually and shall be charged at the minimum rate of interest necessary
to avoid the treatment as interest, under any applicable provisions of the
Code, of any amounts other than amounts stated to be interest under the
deferred payment arrangement.

   (d) TRANSFERABILITY.  An Option shall not be transferable except by will
or by the laws of descent and distribution, and shall be exercisable during
the lifetime of the person to whom the Option is granted only by such person.

   (e) VESTING.  The total number of shares of stock subject to an Option
may, but need not, be allotted in periodic installments (which may, but need
not, be equal).  The Option Agreement may provide that from time to time
during each of such installment periods, the Option may become exercisable
("vest") with respect to some or all of the shares allotted to that period,
and may be exercised with respect to some or all of the shares allotted to
such period and/or any prior period as to which the Option became vested but
was not fully exercised.  During the remainder of the term of the Option (if
its term extends beyond the end of the installment periods), the option may
be exercised from time to time with respect to any shares then remaining
subject to the Option.  The Board or the Committee may, in its discretion,
with the consent of the Optionee, alter or amend the provisions, if any, for
the vesting of any Option.

   (f) SECURITIES LAW COMPLIANCE.  The Company may require any Optionee, or
any person to whom an Option is transferred under subsection 6(d), as a
condition of exercising any such Option, (1) to give written assurances
satisfactory to the Company as to the Optionee's knowledge and experience in
financial and business matters and/or to employ a purchaser representative
reasonably satisfactory to the Company who is knowledgeable and experienced
in financial and business matters, and that he or she is capable of
evaluating, alone or together with the purchaser representative, the merits
and risks of exercising the Option; and (2) to give written assurances
satisfactory to the Company stating that such person is acquiring the stock
subject to the Option for such person's own account and not with any present
intention of selling or otherwise distributing the stock.  These
requirements, and any assurances given pursuant to such requirements, shall
be inoperative if (i) the issuance of the shares upon the exercise of the
Option has been registered under a then currently effective registration
statement under the Securities Act of 1933, as amended (the "Securities
Act"), or (ii) as to any particular requirement, a determination is made by
counsel for the Company that such requirement need not be met in the
circumstances under the then applicable securities law.

   (g) TERMINATION OF EMPLOYMENT OR RELATIONSHIP AS A DIRECTOR OR
CONSULTANT.  In the event an Optionee's Continuous Status as an Employee,
Director or Consultant terminates (other than upon the Optionee's death or
Disability), the Optionee may exercise his or her Option, but only within
such period of time as is determined by the Board (in no event later than the
expiration of the term of such Option as set forth in the Option Agreement)
(the "Post-Termination Exercise Period"), and only to the extent that the
Optionee was entitled to exercise it at the date of termination.  In the case
of an Incentive Stock Option, the Board shall determine the Post-Termination
Exercise Period (in no event to exceed three (3) months from the date of

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termination) when the Option is granted.  In addition, the Board may at any
time, with the consent of the Optionee, extend the Post-Termination Exercise
Period: provided however that any extension of such period by the Board in
excess of three (3) months from the date of termination shall cause an
Incentive Stock Option so extended to become a Nonstatutory Stock Option,
effective as of the date of the action by the Board.  If, at the date of
termination, the Optionee is not entitled to exercise his or her entire
Option, the shares covered by the unexercisable portion of the Option shall
revert to the Plan.  If, after termination, the Optionee does not exercise
his or her Option within the time specified in the Option Agreement, the
Option shall terminate, and the shares covered by such Option shall revert to
the Plan. Notwithstanding the foregoing, the Board shall have the power to
permit an option to continue to vest during the Post Termination Exercise
Period.

   (h) DISABILITY OF OPTIONEE.  In the event an Optionee's Continuous
Status as an Employee, Director or Consultant terminates as a result of the
Optionee's Disability, the Optionee may exercise his or her Option, but only
within twelve (12) months from the date of such termination (or such shorter
period specified in the Option Agreement), and only to the extent that the
Optionee was entitled to exercise it at the date of such termination (but in
no event later than the expiration of the term of such Option as set forth in
the Option Agreement).  If, at the date of termination, the Optionee is not
entitled to exercise his or her entire Option, the shares covered by the
unexercisable portion of the Option shall revert to the Plan.  If, after
termination, the Optionee does not exercise his or her Option within the time
specified herein, the Option shall terminate, and the shares covered by such
Option shall revert to the Plan.

   (i) DEATH OF OPTIONEE.  In the event of the death of an Optionee, the
Option shall fully vest and may be exercised at any time within eighteen (18)
months following the date of death (or such other period specified in the
Option Agreement but in no event later than the expiration of the term of
such Option as set forth in the Option Agreement), by the Optionee's estate
or by a person who acquired the right to exercise the Option by bequest or
inheritance.  If, after death, the Optionee's estate or a person who acquired
the right to exercise the Option by bequest or inheritance does not exercise
the Option within the time specified herein, the Option shall terminate, and
the shares covered by such Option shall revert to the Plan.

   (j) EARLY EXERCISE.  The Option may, but need not, include a provision
whereby the Optionee may elect at any time while an Employee, Director or
Consultant to exercise the Option as to any part or all of the shares subject
to the Option prior to the full vesting of the Option.  Any unvested shares
so purchased may be subject to a repurchase right in favor of the Company or
to any other restriction the Board determines to be appropriate.

   (k) WITHHOLDING.  To the extent provided by the terms of an Option
Agreement, the Optionee may satisfy any federal, state or local tax
withholding obligation relating to the exercise of such Option by any of the
following means or by a combination of such means: (1) tendering a cash
payment; (2) authorizing the Company to withhold shares from the shares of
the common stock otherwise issuable to the participant a result of the
exercise of the Option;

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or (3) delivering to the Company owned and unencumbered shares of the common
stock of the Company.

   (l) RE-LOAD OPTIONS.  Without in any way limiting the authority of the
Board or Committee to make or not to make grants of Options hereunder, the
Board or Committee shall have the authority (but not an obligation) to
include as part of any Option Agreement a provision entitling the Optionee to
a further Option (a "Re-Load Option") in the event the Optionee exercises the
Option evidenced by an Option agreement, in whole or in part, by surrendering
other shares of Common Stock in accordance with this Plan and the terms and
conditions of the Option Agreement.  Any such Re-Load Option (i) shall be for
a number of shares equal to the number of shares surrendered as part or all
of the exercise price of such Option; (ii) shall have an expiration date
which is the same as the expiration date of the Option the exercise of which
gave rise to such Re-Load Option; and (iii) shall have an exercise price
which is equal to one hundred percent (100%) of the Fair Market Value of the
Common Stock subject to the Re-Load Option on the date of exercise of the
original Option or, in the case of a Re-Load Option which is an Incentive
Stock Option and which is granted to a 10% stockholder (as described in
subparagraph 5(c)) shall have an exercise price which is equal to one hundred
ten percent (110%) of the Fair Market Value of the stock subject to the
Re-Load Option on the date of exercise of the original Option.

   Any such Re-Load Option may be an Incentive Stock Option or a Nonqualified
Stock Option, as the the Board or Committee may designate at the time of the
grant of the original Option, provided, however, that the designation of any
Re-Load Option as an Incentive Stock Option shall be subject to the one
hundred thousand dollars ($100,000) annual limitation on exercisability of
Incentive Stock Options described in subparagraph 12(d) of the Plan and in
Section 422(d) of the Code.  There shall be no Re-Load Options on a Re-Load
Option.  Any such Re-Load Option shall be subject to the availability of
sufficient shares under subparagraph 4(a) and shall be subject to such other
terms and conditions as the Board or Committee may determine.

7. TERMS OF STOCK BONUSES AND PURCHASES OF RESTRICTED STOCK

   Each stock bonus or restricted stock purchase agreement shall be in such
form and shall contain such terms and conditions as the Board or the
Committee shall deem appropriate.  The terms and conditions of stock bonus or
restricted stock purchase agreements may change from time to time, and the
terms and conditions of separate agreements need not be identical, but each
stock bonus or restricted stock purchase agreement shall include (through
incorporation of provisions hereof by reference in the agreement or
otherwise) the substance of each of the following provisions as appropriate:

   (a) PURCHASE PRICE.  The purchase price under each stock purchase
agreement shall be such amount as the Board or Committee shall determine and
designate in such agreement.  Notwithstanding the foregoing, the Board or the
Committee may determine that

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eligible participants in the Plan may be awarded stock pursuant to a stock
bonus agreement in consideration for past services actually rendered to the
Company or for its benefit.

   (b) TRANSFERABILITY.  No rights under a stock bonus or restricted stock
purchase agreement shall be assignable by an participant under the Plan,
either voluntarily or by operation of law, except where such assignment is
required by law or expressly authorized by the terms of the applicable stock
bonus or restricted stock purchase agreement.

   (c) CONSIDERATION.  The purchase price of stock acquired pursuant to a
stock purchase agreement shall be paid either (i) in cash at the time of
purchase; (ii) at the discretion of the Board or the Committee, according to
a deferred payment or other arrangement with the person to whom the stock is
sold; or (iii) in any other form of legal consideration that may be
acceptable to the Board or the Committee in their discretion.
Notwithstanding the foregoing, the Board or the Committee to which
administration of the Plan has been delegated may award stock pursuant to a
stock bonus agreement in consideration for past services actually rendered
to the Company or for its benefit.

   (d) VESTING.  Shares of stock sold or awarded under the Plan may, but
need not, be subject to a repurchase option in favor of the Company in
accordance with a vesting schedule to be determined by the Board or the
Committee.

   (e) TERMINATION OF EMPLOYMENT OR RELATIONSHIP AS A DIRECTOR OR
CONSULTANT.  In the event a Participant's Continuous Status as an Employee,
Director or Consultant terminates, the Company may repurchase or otherwise
reacquire any or all of the shares of stock held by that person which have
not vested as of the date of termination under the terms of the stock bonus
or restricted stock purchase agreement between the Company and such person.

8.  STOCK APPRECIATION RIGHTS

   (a) The Board or Committee shall have full power and authority,
exercisable in its sole discretion, to grant Stock Appreciation Rights to
Employees or Directors of or Consultants to, the Company or its Affiliates
under the Plan.  Each such right shall entitle the holder to a distribution
based on the appreciation in the fair market value per share of a designated
amount of stock.

   (b) three types of Stock Appreciation Rights shall be authorized for
issuance under the Plan:

            (i) TANDEM STOCK APPRECIATION RIGHTS.  Tandem Rights will be
granted appurtenant to an Option and will require the holder to elect between
the exercise of the underlying Option for shares of stock and the surrender,
in whole or in part, of such Option for an appreciation distribution equal to
the excess of (A) the Fair Market Value (on the date of Option surrender) of
vested shares of stock purchasable under the surrendered Option over (B) the
aggregate exercise price payable for such shares.

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            (ii) CONCURRENT STOCK APPRECIATION RIGHTS.  Concurrent Rights
will be granted appurtenant to an Option and may apply to all or any portion
of the shares of stock subject to the underlying Option and will be exercised
automatically at the same time the Option is exercised for those shares.  The
appreciation distribution to which the holder of such concurrent right shall
be entitled upon exercise of the underlying Option shall be in an amount
equal to the excess of (A) the aggregate fair market value (at date of
exercise) of the vested shares purchased under the underlying Option with
such concurrent rights over (B) the aggregate exercise price paid for those
shares.

            (iii) INDEPENDENT STOCK APPRECIATION RIGHTS.  Independent Rights
may be granted independently of any Option and will entitle the holder upon
exercise to an appreciation distribution equal in amount to the excess of (A)
the aggregate fair market value (at the date of exercise) of a number of
shares of stock equal to the number of vested share equivalents exercised at
such time (as described in subsection 7(c)(iii)(B)) over (B) the aggregate
fair market value of such number of shares of stock at the date of grant.

   (c) The terms and conditions applicable to each Tandem Right, Concurrent
Right and Independent Right shall be as follows:

            (i) TANDEM RIGHTS

                     (A) Tandem Rights may be tied to either Incentive
Stock Options or Nonstatutory Stock Options.  Each such right shall, except
as specifically set forth below, be subject to the same terms and conditions
applicable to the particular Option to which it pertains.  If Tandem Rights
are granted appurtenant to an Incentive Stock Option, they shall satisfy any
applicable Treasury Regulations so as not to disqualify such Option as an
Incentive Stock Option under the Code.

                     (B) The appreciation distribution payable on the
exercised Tandem Right shall be in cash in an amount equal to the excess of
(I) the fair market value (on the date of the Option surrender) of the number
of shares of stock covered by that portion of the surrendered Option in which
the optionee is vested over (II) the aggregate exercise price payable for
such vested shares.

            (ii)  CONCURRENT RIGHTS

                     (A)  Concurrent Rights may be tied to any or all of the
shares of stock subject to any Incentive Stock Option or Nonstatutory Stock
Option grant made under the Plan.  A Concurrent Right shall, except as
specifically set forth below, be subject to the same terms and conditions
applicable to the particular Option grant to which it pertains.

                     (B)  A Concurrent Right shall be automatically exercised
at the same time the underlying Option is exercised with respect to the
particular shares of stock to which the Concurrent Right pertains.

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                     (C)  The appreciation distribution payable on an
exercised Concurrent Right shall be in cash in an amount equal to such
portion as shall be determined by the Board or the Committee at the time of
the grant of the excess of (I) the aggregate fair market value (on the
Exercise Date) of the vested shares of stock purchased under the underlying
Option which have Concurrent Rights appurtenant to them over (II) the
aggregate exercise price paid for such shares.

            (iii)  INDEPENDENT RIGHTS

                     (A)  Independent Rights shall, except as specifically
set forth below, be subject to the same terms and conditions applicable to
Nonstatutory Stock Options as set forth in Section 6.  They shall be
denominated in share equivalents.

                     (B)  The appreciation distribution payable on the
exercised Independent Right shall be in an amount equal to the excess of (I)
the aggregate fair market value (on the date of the exercise of the
Independent Right) of a number of shares of Company stock equal to the number
of share equivalents in which the holder is vested under such Independent
right, and with respect to which the holder is exercising the Independent
Right on such date, over (II) the aggregate fair market value (on the date of
the grant of the Independent Right) of such number of shares of Company stock.

                     (C)  The appreciation distribution payable on the
exercised Independent Right may be paid, in the discretion of the Board or
the Committee, in cash, in shares of stock or in a combination of cash and
stock.  Any shares of stock so distributed shall be valued at fair market
value on the date the Independent Right is exercised.

            (iv)  TERMS APPLICABLE TO TANDEM RIGHTS
                  CONCURRENT RIGHTS AND INDEPENDENT RIGHTS

                     (A)  To exercise any outstanding Tandem, Concurrent or
Independent Right, the holder must provide written notice of exercise to the
Company in compliance with the provisions of the instrument evidencing such
right.

                     (B)  If a Tandem, Concurrent or Independent Right is
granted to an individual who is at the time subject to Section 16(b) of the
Exchange Act (a "Section 16(b) Insider"), then the instrument of grant shall
incorporate all the terms and conditions at the time necessary to assure that
the subsequent exercise of such right shall qualify for the safe-harbor
exemption from short-swing profit liability provided by Rule 16b-3
promulgated under the Exchange Act (or any successor rule or regulation).

                     (C)  No limitation shall exist on the aggregate amount
of cash payments the Company may make under the Plan in connection with the
exercise of Tandem, Concurrent or Independent Rights.

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   9. CANCELLATION AND RE-GRANT OF OPTIONS

      The Board or the Committee shall have the authority to effect, at any
time and from time to time, with the consent of the affected holders of
Options and/or Stock Appreciation Rights, (i) the repricing of any
outstanding Options and/or any Stock Appreciation Rights under the Plan
and/or (ii) the cancellation of any outstanding Options and/or any Stock
Appreciation Rights under the Plan and the grant in substitution therefor of
new Options and/or Stock Appreciation Rights under the Plan covering the same
or different numbers of shares of stock, but having an exercise price per
share not less than eighty-five percent (85%) of the Fair Market Value (one
hundred percent (100%) of the Fair Market Value in the case of an Incentive
Stock Option or, in the case of a 10% stockholder (as described in
subparagraph 5(c)), not less than one hundred ten percent (110%) of the Fair
Market Value) per share of stock on the new grant date.

   10.   COVENANTS OF THE COMPANY

         (a)  During the terms of the Stock Awards, the Company shall keep
available at all times the number of shares of stock required to satisfy such
Stock Awards up to the number of shares of stock authorized under the Plan.

         (b)  The Company shall seek to obtain from each regulatory
commission or agency having jurisdiction over the Plan such authority as may
be required to issue and sell shares of stock under the Stock Awards:
provided, however, that this undertaking shall not require the Company to
register under the Securities Act either the Plan, any Stock Award or any
stock issued or issuable pursuant to any such Stock Award.  If, after
reasonable efforts, the Company is unable to obtain from any such regulatory
commission or agency the authority which counsel for the Company deems
necessary for the lawful issuance and sale of stock under the Plan, the
Company shall be relieved from any liability for failure to issue and sell
stock under such Stock Awards unless and until such authority is obtained.

   11.   USE OF PROCEEDS FROM STOCK

         Proceeds from the sale of stock pursuant to Stock Awards shall
constitute general funds of the Company.

   12.   MISCELLANEOUS

         (a)  The Board shall have the power to accelerate the time at which
a Stock Award may first be exercised or the time during which a Stock Award
or any part thereof will vest, notwithstanding the provisions in the Stock
Award stating the time at which it may first be exercised or the time during
which it will vest.

                                      13

<PAGE>

         (b)  Neither an Optionee nor any person to whom an Option is
transferred under subsection 6(d) shall be deemed to be the holder of, or to
have any of the rights of a holder with respect to, any shares subject to
such Option unless and until such person has satisfied all requirements for
exercise of the Option pursuant to its terms.

         (c)  Throughout the term of any Option, the Company shall deliver to
the holder of such Option, not later than one hundred twenty (120) days after
the close of each of the Company's fiscal years during the Option term, a
balance sheet and an income statement.

         (d)  Nothing in the Plan or any instrument executed or Stock Award
granted pursuant thereto shall confer upon any Employee, Director,
Consultant, Optionee, or other hold of Stock Awards any right to continue in
the employ of the Company or any Affiliate (or to continue acting as a
Director or Consultant) or shall affect the right of the Company or any
Affiliate to terminate the employment or relationship as a Director or
Consultant of any Employee, Director, Consultant or Optionee with or without
cause.

         (e)  To the extent that the aggregate Fair Market Value (determined
at the time of grant) of stock with respect to which Incentive Stock Options
granted after 1986 are exercisable for the first time by any Optionee during
any calendar year under all plans of the Company and its Affiliates exceeds
one hundred thousand dollars ($100,000), the Options or portions thereof
which exceed such limit (according to the order in which they were granted)
shall be treated as Nonstatutory Stock Options.

   13.   ADJUSTMENTS UPON CHANGES IN STOCK

         (a)  If any change is made in the stock subject to the Plan, or
subject to any Stock Award (through merger, consolidation, reorganization,
recapitalization, stock dividend, dividend in property other than cash, stock
split, liquidating dividend, combination of shares, exchange of shares,
change in corporate structure or otherwise), the Plan and outstanding Stock
Awards will be appropriately adjusted in the class(es) and maximum number of
shares subject to the Plan and the class(es) and number of shares and price
per share of stock subject to outstanding Stock Awards.

        (b)  Subject to subparagraph 13(c) below, in the event of:  (1) a
dissolution or liquidation of the Company; (2) a merger or consolidation in
which the Company is not the surviving corporation; or (3) a reverse merger
in which the Company is the surviving corporation but the shares of the
Company's common stock outstanding immediately preceding the merger are
converted by virtue of the merger into other property, whether in the form of
securities, cash or otherwise, then, at the sole discretion of the Board and
to the extent permitted by applicable law: (i) any surviving corporation
shall assume any Stock Awards outstanding under the Plan or shall substitute
similar Stock Awards for those outstanding under the Plan, (ii) such Stock
Awards shall continue in full force and effect, or (iii) the time during
which such Stock Awards become vested or may be exercised shall be
accelerated and any outstanding unexercised rights under any Stock Awards
terminated if not exercised prior to such event.

                                      14

<PAGE>

        (c)  In the event of any dissolution, liquidation, merger,
consolidation or reverse merger described in subparagraph 13(b) hereof (each,
an "Event"), (i) the vesting of that portion, if any, of any Stock Award held
by an employee of the Company who at the time of such Event has the title of
Vice President or a title senior to that of Vice President, which by the
terms of such Stock Award will vest within 24 months of such Event, shall be
accelerated to permit exercise prior to such Event, and (ii) the vesting of
that portion, if any, of any Stock Award held by an employee of the Company
who at the time of such Event has the title of Director or a title senior to
that of Director but who is not eligible for the accelerated vesting provided
in clause (i) above, which by the terms of such Stock Award will vest within
12 months of such Event, shall be accelerated to permit exercise prior to
such Event.  The acceleration provided for in this subparagraph (c) shall be
in addition to any other adjustment provided for in the Plan.

    14. AMENDMENT OF THE PLAN

        (a)  The Board at any time, and from time to time, may amend the
Plan.  However, except as provided in Section 13 relating to adjustments upon
changes in stock, no amendment shall be effective unless approved by the
stockholders of the Company within twelve (12) months before or after the
adoption of the amendment, where the amendment will:

            (i)   Increase the number of shares reserved for Stock Awards
under the Plan;

            (ii)  Modify the requirements as to eligibility for participation
in the Plan to the extent such modification requires stockholder approval in
order for the Plan to satisfy the requirements of Section 422 of the Code; or

            (iii) Modify the Plan in any other way if such modification
requires stockholder approval in order for the Plan to satisfy the
requirements of Section 422 of the Code or to comply with the requirements of
Rule 16b-3.

        (b)  It is expressly contemplated that the Board may amend the Plan
in any respect the Board deems necessary or advisable to provide Optionees
with the maximum benefits provided or to be provided under the provisions of
the Code and the regulations promulgated thereunder relating to Incentive
Stock Options and/or to bring the Plan and/or Incentive Stock Options granted
under it into compliance therewith.

        (c)  Rights and obligations under any Stock Award granted before
amendment of the Plan shall not be altered or impaired by any amendment of
the Plan unless (i) the Company requests the consent of the person to whom
the Stock Award was granted and (ii) such person consents in writing.

                                      15

<PAGE>

    15. TERMINATION OR SUSPENSION OF THE PLAN

        (a)  The Board may suspend or terminate the Plan at any time.  Unless
sooner terminated, the Plan shall terminate on December 9, 2003.  No Stock
Awards may be granted under the Plan while the Plan is suspended or after it
is terminated.

        (b)  Rights and obligations under any Stock Award granted while the
Plan is in effect shall not be altered or impaired by suspension or
termination of the Plan, except with the consent of the person to whom the
Stock Award was granted.

    16. EFFECTIVE DATE OF PLAN

        The Plan shall become effective as determined by the Board, but no
Stock Awards granted under the Plan to officers of the Company shall be
exercisable unless and until the Plan has been approved by the stockholders
of the Company.

                                      16

<PAGE>

                                 AMENDMENT NO. 1 TO THE
                                       CORTECH, INC.
                               1993 EQUITY INCENTIVE PLAN

     This Amendment No. 1 to the Cortech, Inc. 1993 Equity Incentive Plan
(the "Plan") was adopted by the Board of Directors on September 18, 1995, to
provide as follows:

     Subsection 13(c) is hereby amended to read in its entirety as follows:

     (c)  In the event of a Change Of Control (as defined below), the time at
     which Stock Awards which are Options or Stock Appreciation Rights held
     by any person who is an Employee, Director or Consultant at the time of
     the occurrence of such event may be exercised (and become fully vested),
     shall be accelerated to provide the optionee with a reasonable
     opportunity to exercise the fully-vested Stock Award in full, and any
     outstanding unexercised rights under Stock Awards held by such persons
     shall terminate if not exercised prior to or coincident with the
     occurrence of such event (or if an event described in clause (v) or (vi)
     below occurs, if not exercised within a reasonable period of time, which
     shall be no less than thirty (30) days, following the occurrence of such
     event).  For any Stock Award which is a restricted stock bonus or a
     restricted stock purchase, in the event of a Change of Control (as defined
     below), the time during which such a Stock Award may become fully vested
     shall be accelerated immediately prior to the occurrence of such event.

     "Change Of Control" shall mean (i) a merger or consolidation in which
     the Company is not the surviving corporation; (ii) a reverse merger in
     which the Company is the surviving corporation but the shares of the
     Company's common stock outstanding immediately preceding the merger are
     converted by virtue of the merger into other property, whether in the
     form of securities, cash or otherwise; (iii) any other capital
     reorganization in which more than thirty percent (30%) of the shares of
     the Company entitled to vote are exchanged; (iv) a transaction or group
     of related transactions involving the sale of all or substantially all
     of the Company's assets; (v) the acquisition by any person, entity or
     group (excluding any employee benefit plan, or related trust, sponsored
     or maintained by the Company or any subsidiary of the Company) of the
     beneficial ownership, directly or indirectly, of securities of the
     Company representing more than thirty percent (30%) of the combined
     voting power in the election of directors; or (vi) a change in the
     composition of the Company's Board of Directors such that, during any
     period of two consecutive years, individuals who, at the beginning of
     such period, constitute the Board, together with individuals who are
     Approved New Directors (as defined below), cease for any reason to have
     authority to cast at least a majority of the votes which all directors
     on the Board are entitled to vote.

     An "Approved New Director" shall be a Board member whose election, or
     the nomination for election by the Company's stockholders, was approved
     by a vote of a majority of the votes entitled to be cast by the
     directors then still in office who were directors at the beginning of
     the period.

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