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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
                   Approved by Stockholders on ____________, 1997


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 one hundred twenty-five
thousand (125,000) 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

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discretion, including (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.

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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 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.

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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 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.

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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.

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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