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                                                                  EXHIBIT 10.22


                        ARRIS PHARMACEUTICAL CORPORATION

                 1994 NON-EMPLOYEE DIRECTORS' STOCK OPTION PLAN

                            ADOPTED ON APRIL 20, 1994
                    APPROVED BY STOCKHOLDERS ON JUNE 7, 1994
                           AMENDED ON FEBRUARY 6, 1997
                          AMENDED ON NOVEMBER 10, 1997
                   APPROVED BY STOCKHOLDERS ON JANUARY 7, 1998



1. PURPOSE.

        (a) The purpose of the 1994 Non-Employee Directors' Stock Option Plan
(the "Plan") is to provide a means by which each new director of Arris
Pharmaceutical Corporation (the "Company") who is not otherwise an employee of
the Company or of any Affiliate of the Company (each such person being hereafter
referred to as a "Non-Employee Director") will be given an opportunity to
purchase stock of the Company.

        (b) The word "Affiliate" as used in the Plan means any parent
corporation or subsidiary corporation of the Company as those terms are defined
in Sections 424(e) and (f), respectively, of the Internal Revenue Code of 1986,
as amended from time to time (the "Code").

        (c) The Company, by means of the Plan, seeks to secure and retain the
services of persons capable of serving as Non-Employee Directors of the Company,
and to provide incentives for such persons to exert maximum efforts for the
success of the Company.

2. ADMINISTRATION.

        (a) The Plan shall be administered by the Board of Directors of the
Company (the "Board") unless and until the Board delegates administration to a
committee, as provided in subparagraph 2(b).



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        (b) The Board may delegate administration of the Plan to a committee
composed of two (2) or more members of the Board (the "Committee"), all of the
members of which Committee may (but need not) be, in the discretion of the
Board, "non-employee directors" within the meaning of Rule 16b-3 promulgated
under the Securities Exchange Act of 1934, as amended (the "Exchange Act") or
"outside directors" within the meaning of Section 162(m) of the Code. 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, 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.

3. SHARES SUBJECT TO THE PLAN.

        (a) Subject to the provisions of paragraph 10 relating to adjustments
upon changes in stock, the stock that may be sold pursuant to options granted
under the Plan shall not exceed in the aggregate four hundred seventy-five
thousand (475,000) shares of the Company's common stock. If any option granted
under the Plan shall for any reason expire or otherwise terminate without having
been exercised in full, the stock not purchased under such option shall again
become available for the Plan.

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

4. ELIGIBILITY.

        Options shall be granted only to Non-Employee Directors of the Company.

5. NON-DISCRETIONARY GRANTS.



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        (a) Each person who is elected or appointed for the first time to serve
as a Non-Employee Director on or after February 6, 1997 shall, upon the date of
such initial election or appointment, be granted an option to purchase thirty
thousand (30,000) shares of common stock of the Company on the terms and
conditions set forth herein.

        (b) On the date of the Company's annual meeting of its stockholders each
year, commencing with the 1997 annual meeting, each person who is then serving
as a Non-Employee Director and has continuously served as a Non-Employee
Director for at least the preceding three (3) months shall be granted an option
to purchase five thousand (5,000) shares of common stock of the Company on the
terms and conditions set forth herein.

6. OPTION PROVISIONS.

        Each option shall contain the following terms and conditions:

        (a) The term of each option commences on the date it is granted and,
unless sooner terminated as set forth herein, expires on the date ("Expiration
Date") ten (10) years from the date of grant. If the optionee's service as a
Director or as an employee of or consultant to the Company or any Affiliate of
the Company terminates for any reason or for no reason, the option shall
terminate on the earlier of the Expiration Date or the date three (3) months
following the date of termination of service; provided, however, that if such
termination of service is due to the optionee's death, the option shall
terminate on the earlier of the Expiration Date or twelve (12) months following
the date of the optionee's death. In any and all circumstances, an option may be
exercised following termination of the optionee's service as a Director of the
Company only as to that number of shares as to which it was exercisable on the
date of termination of such service under the provisions of subparagraph 6(e).



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        (b) The exercise price of each option shall be one hundred percent
(100%) of the fair market value of the stock subject to such option on the date
such option is granted.

        (c) The optionee may elect to make payment of the exercise price under
one of the following alternatives:

                   (i) Payment of the exercise price per share in cash at the
time of exercise; or

                   (ii) Provided that at the time of the exercise the Company's
common stock is publicly traded and quoted regularly in the Wall Street Journal,
payment by delivery of shares of common stock of the Company already owned by
the optionee, held for the period required to avoid a charge to the Company's
reported earnings, and owned free and clear of any liens, claims, encumbrances
or security interest, which common stock shall be valued at fair market value on
the date preceding the date of exercise; or

                  (iii) Payment by a combination of the methods of payment
specified in subparagraph 6(c)(i) and 6(c)(ii) above.

        Notwithstanding the foregoing, this option may be exercised pursuant to
a program developed under Regulation T as promulgated by the Federal Reserve
Board which results in the receipt of cash (or check) by the Company prior to
the issuance of shares of the Company's common stock.

        (d) 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 or by his or her
guardian or legal representative, unless otherwise specified in the option, in
which case the option may be transferred upon such terms and conditions as are
set forth in the option, as the Board or the Committee shall determine in its
discretion, including



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(without limitation) pursuant to a "domestic relations order." Notwithstanding
the foregoing, the person to whom an option is granted may, by delivering
written notice to the Company, in a form satisfactory to the Company, designate
a third party who, in the event of the death of the optionee, shall thereafter
be entitled to exercise the option.

        (e) The option shall become exercisable in installments over a period of
four (4) years from the date of grant at the rate of twenty five percent (25%)
of the total shares granted under such option in four (4) equal annual
installments commencing on the date one year after the date of grant of the
option, provided that the optionee has, during the entire period prior to such
vesting date, continuously served as a Director or as an employee of or
consultant to the Company or any Affiliate of the Company, whereupon such option
shall become fully exercisable in accordance with its terms with respect to that
portion of the shares represented by that installment.

        (f) The Company may require any optionee, or any person to whom an
option is transferred under subparagraph 6(d), as a condition of exercising any
such option: (i) to give written assurances satisfactory to the Company as to
the optionee's knowledge and experience in financial and business matters; and
(ii) 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 laws.



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        (g) Notwithstanding anything to the contrary contained herein, an option
may not be exercised unless the shares issuable upon exercise of such option are
then registered under the Securities Act or, if such shares are not then so
registered, the Company has determined that such exercise and issuance would be
exempt from the registration requirements of the Securities Act.

7. COVENANTS OF THE COMPANY.

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

        (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 upon exercise of the options granted under the
Plan; provided, however, that this undertaking shall not require the Company to
register under the Securities Act either the Plan, any option granted under the
Plan, or any stock issued or issuable pursuant to any such option. If 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 upon exercise of such options.

8. USE OF PROCEEDS FROM STOCK.

        Proceeds from the sale of stock pursuant to options granted under the
Plan shall constitute general funds of the Company.

9. MISCELLANEOUS.

        (a) Neither an optionee nor any person to whom an option is transferred
under subparagraph 6(d) shall be deemed to be the holder of, or to have any of
the rights of a holder with



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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.

        (b) Nothing in the Plan or in any instrument executed pursuant thereto
shall confer upon any Non-Employee Director any right to continue in the service
of the Company or any Affiliate or shall affect any right of the Company, its
Board or stockholders or any Affiliate to terminate the service of any
Non-Employee Director with or without cause.

        (c) No Non-Employee Director, individually or as a member of a group,
and no beneficiary or other person claiming under or through such Non-Employee
Director, shall have any right, title or interest in or to any option reserved
for the purposes of the Plan except as to such shares of common stock, if any,
as shall have been reserved for such Non-Employee Director pursuant to any
previous option grant.

        (d) In connection with each option made pursuant to the Plan, it shall
be a condition precedent to the Company's obligation to issue or transfer shares
to a Non-Employee Director, or to evidence the removal of any restrictions on
transfer, that such Non-Employee Director make arrangements satisfactory to the
Company to insure that the amount of any federal or other withholding tax
required to be withheld with respect to such sale or transfer, or such removal
or lapse, is made available to the Company for timely payment of such tax.

10. ADJUSTMENTS UPON CHANGES IN STOCK.

        (a) If any change is made in the stock subject to the Plan, or subject
to any option granted under the Plan, without the receipt of consideration by
the Company (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 other transaction not involving the receipt of consideration by the
Company), the Plan



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will be appropriately adjusted in the class(es) and maximum number of shares
subject to the Plan pursuant to subparagraph 3(a), and the outstanding options
will be appropriately adjusted in the class(es) and number of shares and price
per share of stock subject to such outstanding options. Such adjustments shall
be made by the Board or the Committee, the determination of which shall be
final, binding and conclusive. (The conversion of any convertible securities of
the Company shall not be treated as a "transaction not involving the receipt of
consideration by the Company".)

        (b) In the event of: (1) a merger or consolidation in which the Company
is not the surviving corporation; (2) 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; or (3) any other capital reorganization in which more than fifty
percent (50%) of the shares of the Company entitled to vote are exchanged, the
time during which options outstanding under the Plan may be exercised shall be
accelerated and the options terminated if not exercised prior to such event.

11. AMENDMENT OF THE PLAN.

        (a) The Board at any time, and from time to time, may amend the Plan.
Except as provided in paragraph 10 relating to adjustments upon changes in
stock, no amendment shall be effective unless approved by the stockholders of
the Company to the extent stockholder approval is necessary for the Plan to
satisfy the requirements of Rule 16b-3 under the Exchange Act or any Nasdaq or
securities exchange listing requirements.

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



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12. 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 April 1, 2004. No options may be
granted under the Plan while the Plan is suspended or after it is terminated.

        (b) Rights and obligations under any option 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 option was granted.

        (c) The Plan shall terminate upon the occurrence of any of the events
described in Section 10(b) above.

13. EFFECTIVE DATE OF PLAN; CONDITIONS OF EXERCISE.

        (a) The Plan shall become effective upon adoption by the Board of
Directors, subject to the condition subsequent that the Plan is approved by the
stockholders of the Company.

        (b) No option granted under the Plan shall be exercised or exercisable
unless and until the condition of subparagraph 13(a) above has been met.



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