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                                                                    EXHIBIT 10.8

                                ICOS CORPORATION

                    1991 STOCK OPTION PLAN FOR NONEMPLOYEE
                                   DIRECTORS
                   AMENDED AND RESTATED AS OF JANUARY 8, 1997



                                   ARTICLE I
                                    PURPOSE

     The purposes of the ICOS Corporation 1991 Stock Option Plan for Nonemployee
Directors (the "Plan") are to attract and retain the services of experienced and
knowledgeable nonemployee directors of ICOS Corporation (the "Corporation") and
to provide an incentive for such directors to increase their proprietary
interest in the Corporation's long-term success and progress.

                                   ARTICLE II
                           SHARES SUBJECT TO THE PLAN

     The total number of shares of common stock (the "Shares") of the
Corporation for which options may be granted under the Plan is 950,000, subject
to adjustment in accordance with Article VI hereof.  The Shares shall be shares
presently authorized but unissued or subsequently acquired by the Corporation
and shall include shares representing the unexercised portion of any option
granted under the Plan which expires or terminates without being exercised in
full.

                                  ARTICLE III
                           ADMINISTRATION OF THE PLAN

     The administrator of the Plan (the "Plan Administrator") shall consist of a
committee appointed by the Board of Directors of the Corporation (the "Board").
Subject to the terms of the Plan, the Plan Administrator shall have the power to
construe the provisions of the Plan, to determine all questions arising
thereunder and to adopt and amend such rules and regulations for the
administration of the Plan as it may deem desirable.  No member of the Plan
Administrator shall participate in any vote by the Plan Administrator on any
matter materially affecting the rights of any such member under the Plan.

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                                   ARTICLE IV
                           PARTICIPATION IN THE PLAN

     Each Director of the Corporation elected or appointed who is not otherwise
an employee of the Corporation or any subsidiary ("Eligible Director") shall
receive the following option grants under the Plan:

1.   INITIAL GRANTS

     An initial grant (an "Initial Grant") of an option to purchase that number
of shares calculated by dividing $100,000 (such dollar amount to be increased by
$10,000 each year for grants made in each year beginning after fiscal year 1992)
by the Exercise Price, as hereinafter defined, shall automatically be granted to

     (a)  each Eligible Director immediately following the Board's approval of
the Plan and

     (b)  each Eligible Director upon the earlier of the Director's initial
election or appointment as a Director of the Corporation.

     The Initial Grants shall vest annually over two years from the earlier of
the Director's initial election or appointment as a Director of the Corporation
in accordance with the schedule set forth in Article V.

2.   ADDITIONAL GRANTS

     Commencing with the 1992 annual meeting of stockholders of the Corporation
as specified in the Corporation's By-laws (the "Annual Meeting"), each Eligible
Director shall automatically receive an additional grant (an "Additional Grant")
of an option to purchase that number of shares calculated by dividing $100,000
(such dollar amount to be increased by $10,000 each year for grants made in each
year beginning after fiscal year 1992) by the Exercise Price, as hereinafter
defined, immediately following each year's Annual Meeting; provided that a
Director who has received an Initial Grant within five months prior to an Annual
Meeting shall not receive an Additional Grant until the next year's Annual
Meeting.

     Additional Grants shall vest annually over two years from the earlier of
the Director's initial election or appointment as a Director of the Corporation
in accordance with the schedule set forth in Article V.

                                   ARTICLE V
                                  OPTION TERMS

     Each option granted to an Eligible Director under the Plan and the issuance
of Shares thereunder shall be subject to the following terms:

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1.   OPTION AGREEMENT

     Each option granted under the Plan shall be evidenced by an option
agreement ("Agreement") duly executed on behalf of the Corporation and by the
Eligible Director to whom such option is granted.  Each Agreement shall comply
with and be subject to the terms and conditions of the Plan.  Any Agreement may
contain such other terms, provisions and conditions not inconsistent with the
Plan as may be determined by the Plan Administrator.

2.   OPTION EXERCISE PRICE

     The option exercise price (the "Exercise Price") for an option granted
under the Plan shall be the fair market value of the Shares covered by the
option at the time the option is granted.  For purposes of the Plan, "fair
market value" shall mean the closing price or, if there is no closing price, the
mean between the high and low sale prices for the Shares quoted on the day of
grant on the National Association of Securities Dealers, Inc. Automated
Quotation System or, if the Shares are traded on an exchange, the closing price
on the day of grant on the principal exchange on which such Shares are then
traded.

3.   TIME AND MANNER OF EXERCISE OF OPTION

     Subject to stockholder approval of the Plan, Initial Grants and Additional
Grants shall become exercisable in accordance with the following schedule and
vested portions may be exercised in full at one time or in part from time to
time:
<TABLE>
<CAPTION>

Period of Optionee's Continuous Service
 as a Director With the Corporation
From the Date of Initial Election or      Portion of Grant That Is Exercisable
         Appointment
---------------------------------------   ------------------------------------

        <S>                                        <C>
        After one year                             50%

        After two years                           100%
</TABLE>

     Grants to Directors who have held office for two years or more shall be
fully vested and immediately exercisable, subject to stockholder approval of the
Plan.  If the stockholders of the Corporation fail to approve the Plan at the
next annual meeting of stockholders, all options granted hereunder shall be
deemed null and void.

     Any option may be exercised by giving written notice, signed by the person
exercising the option, to the Corporation stating the number of Shares with
respect to which the option is being exercised, accompanied by payment in full
for such Shares, which payment may be in whole or in part (i) in cash or by
check, (ii) in shares of the common stock of the Corporation already owned for
at least six (6) months by the person exercising the option, valued at fair
market value at the time of such exercise, or (iii) by delivery of a properly
executed exercise notice, together with irrevocable instructions to a broker,
all in accordance with the

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regulations of the Federal Reserve Board, to properly deliver to the Corporation
the amount of sale or loan proceeds to pay the exercise price.

4.   TERM OF OPTIONS

          Each option shall expire ten (10) years from the date of the granting
thereof, but shall be subject to earlier termination as follows:

          (a) In the event of the death of an optionee, the unvested portion of
the options granted to such optionee shall terminate immediately and the vested
portion of the option granted to such optionee may be exercised only within two
(2) years after the date of death of such optionee or prior to the date on which
the option expires by its terms, whichever is earlier, by the estate of such
optionee, or by any person or persons whom the optionee shall have designated in
writing on forms prescribed by and filed with the Corporation or, if no such
designation has been made by the person or persons to whom the optionee's rights
have passed, by will or the laws of descent and distribution.

          (b) In the event that an optionee ceases to be a Director of the
Corporation, the unvested portion of the options granted to such optionee shall
terminate immediately and the vested portion of the option granted to such
optionee may be exercised by him or her only within two (2) years after the date
such optionee ceases to be a Director of the Corporation or prior to the date on
which the option expires by its terms, whichever is earlier.

5.   TRANSFERABILITY

     Options granted under the Plan shall not be transferable, pledgable or
assignable other than (a) by will or the laws of descent and distribution or (b)
by gift or other transfer to either (i) a spouse or other immediate family
member or (ii) any trust or partnership in which the original optionee or such
person's spouse or other immediate family member has a substantial beneficial
interest; provided, however, that any option so assigned or transferred shall be
subject to all the same terms and conditions contained in the instrument
evidencing the award.  During an Optionee's lifetime, any options granted under
this Plan are personal to the Optionee and are exercisable solely by such
Optionee or a permitted assignee or transferee.  An optionee may also, during
the optionee's lifetime, designate a person who may exercise the option after
the optionee's death by giving written notice of such designation to the
Corporation (such designation may be changed from time to time by the optionee
by giving written notice to the Corporation revoking any earlier designation and
making a new designation).  Any attempt to transfer, assign, pledge, hypothecate
or otherwise dispose of any option under the Plan or of any right or privilege
conferred thereby, contrary to the provisions of the Plan, or the sale or levy
or any attachment or similar process upon the rights and privileges conferred
hereby, shall be null and void.

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6.   HOLDING PERIOD

     If an individual subject to Section 16 of the Exchange Act sells shares of
Common Stock obtained upon the exercise of any option granted under this Plan
within six (6) months after the date the option was granted, such sale may
result in short-swing profit recovery under Section 16(b) of the Exchange Act.

7.   PARTICIPANT'S OR SUCCESSOR'S RIGHTS AS STOCKHOLDER

     Neither the recipient of an option under the Plan nor his or her
successor(s) in interest shall have any rights as a stockholder of the
Corporation with respect to any Shares subject to an option granted to such
person until such person becomes a holder of record of such Shares.

8.   REGULATORY APPROVAL AND COMPLIANCE

     The Corporation shall not be required to issue any certificate or
certificates for Shares upon the exercise of an option granted under the Plan,
or record as a holder of record of Shares the name of the individual exercising
an option under the Plan, without obtaining to the complete satisfaction of the
Plan Administrator the approval of all regulatory bodies deemed necessary by the
Plan Administrator, and without complying, to the Plan Administrator's complete
satisfaction, with all rules and regulations under federal, state or local law
deemed applicable by the Plan Administrator.

                                   ARTICLE VI
                              CAPITAL ADJUSTMENTS

     The aggregate number and class of Shares for which options may be granted
under this Plan, the number and class of Shares covered by each outstanding
option and the exercise price per share thereof (but not the total price), shall
all be proportionately adjusted for any increase or decrease in the number of
issued shares of the Corporation's common stock resulting from a split-up or
consolidation of the Corporation's common stock or any like capital adjustment,
or the payment of any stock dividend.

     Upon a merger (other than a merger of the Corporation in which the holders
of the Corporation's common stock immediately prior to the merger have the same
proportionate ownership of common stock in the surviving corporation immediately
after the merger), consolidation, acquisition of property or stock, separation,
reorganization (other than a mere reincorporation or the creation of a holding
company) or liquidation of the Corporation (each a "corporate transaction"), as
a result of which the stockholders of the Corporation receive cash, stock or
other property in exchange for or in connection with their shares of the
Corporation's common stock, the optionee shall have the right immediately prior
to any such corporate transaction to exercise such optionee's option in whole or
in part whether or not the vesting requirements set forth in the option
agreement have been satisfied.  To the extent such option is not exercised, it
shall terminate, except that in the event of a corporate transaction in which
stockholders of the Corporation receive capital stock of another corporation in

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exchange for their shares of the Corporation's common stock, such unexercised
option shall be assumed or an equivalent option shall be substituted by the
successor corporation or a parent or subsidiary of such successor corporation.
Any such assumed or equivalent option shall be fully vested and exercisable with
respect to the total number of shares purchasable under such option.

     Upon a merger of the Corporation in which the holders of the Corporation's
common stock immediately prior to the merger have the same proportionate
ownership of common stock in the surviving corporation immediately after the
merger, a mere reincorporation or the creation of a holding company, each option
outstanding under the Plan shall be assumed or an equivalent option shall be
substituted by the successor corporation or a parent or subsidiary of such
corporation, and the vesting schedule set forth herein shall continue to apply
to such assumed or equivalent option.

     In the event of any adjustment in the number of Shares covered by any
option, any fractional Shares resulting from such adjustment shall be
disregarded and each such option shall cover only the number of full Shares
resulting from such adjustment.

                                  ARTICLE VII
                              EXPENSES OF THE PLAN

     All costs and expenses of the adoption and administration of the Plan shall
be borne by the Corporation, and none of such expenses shall be charged to any
optionee.

                                  ARTICLE VIII
                            APPROVAL OF STOCKHOLDERS

     The Plan shall be effective upon adoption by the Board so long as it
receives approval by the holders of a majority of the Corporation's outstanding
shares of voting capital stock at the next Annual Meeting.

                                   ARTICLE IX
                           COMPLIANCE WITH RULE 16B-3

     It is the intention of the Corporation that the Plan comply in all respects
with the requirements for a "formula plan" within the meaning attributed to that
term for purposes of Rule 16b-3 promulgated under Section 16(b) of the Exchange
Act.  Therefore,  if any Plan provision is later found not to be in compliance
with such requirements, that provision shall be deemed null and void, and in all
events the Plan shall be construed in favor of its meeting such requirements.

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                                   ARTICLE X
                     TERMINATION AND AMENDMENT OF THE PLAN

     The Board may amend, terminate or suspend the Plan at any time, in its sole
and absolute discretion; provided, however, that if required to qualify the Plan
as a formula plan for purposes of Rule 16b-3 promulgated under Section 16 of the
Exchange Act, no amendment may be made more than once every six months that
would change the amount, price, timing or vesting of the Initial Grants and
Additional Grants, other than to comport with changes in the Internal Revenue
Code of 1986, as amended, or the rules and regulations promulgated thereunder;
and provided, further, that to the extent required by any applicable law or
regulation, no amendment that would

          (a) materially increase the number of Shares that may be issued under
     the Plan, or

          (b) otherwise require shareholder approval under any applicable law or
     regulation

shall be made without the approval of a majority of the shares of the
Corporation's common stock represented in person or by proxy and entitled to
vote on the matter at a duly held stockholders' meeting.

                                     *****

     Adopted by the Board of Directors on November 18, 1991 and approved by the
stockholders on May 18, 1992.

     Amendment No. 1 (increasing the number of shares available under the plan
to 600,000) adopted by the Board of Directors on March 9, 1994 and approved by
the stockholders on May 11, 1994.

     Amended and restated by the Board of Directors on December 6, 1995 and
approved by the stockholders on May 8, 1996 with respect to the amendment to
Article II.

     Amended and restated by the Board of Directors on January 8, 1997.

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