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                                                                    EXHIBIT 99.4

                        IDEC PHARMACEUTICALS CORPORATION

                  1993 NON-EMPLOYEE DIRECTORS STOCK OPTION PLAN
                  ---------------------------------------------
                (AMENDED AND RESTATED THROUGH FEBRUARY 20, 1998)

     I. PURPOSE OF THE PLAN

          This 1993 Non-Employee Directors Stock Option Plan (the "Plan") is
intended to promote the interests of IDEC Pharmaceuticals Corporation, a
Delaware corporation (the "Corporation"), by providing the non-employee members
of the Corporation's Board of Directors with the opportunity to acquire a
proprietary interest, or otherwise increase their proprietary interest, in the
Corporation as an incentive for them to remain in the service of the
Corporation.

     II. DEFINITIONS

          For purposes of the Plan, the following definitions shall be in
effect:

               BOARD: the Corporation's Board of Directors.

               CODE: the Internal Revenue Code of 1986, as amended.

               COMMON STOCK: shares of the Corporation's common stock.

               CHANGE IN CONTROL: a change in ownership or control of the
Corporation effected through either of the following transactions:

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

               b. there is a change in the composition of the Board over a
          period of twenty-four (24) consecutive months or less such that a
          majority of the Board members ceases, by reason of one or more proxy
          contests for the election of Board members, to be comprised of
          individuals who either (A) have been Board members continuously since
          the beginning of such period or (B) have been elected or nominated for
          election as Board members during such period by at least a majority of
          the Board members described in clause (A) who were still in office at
          the time such election or nomination was approved by the Board.



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          CORPORATE TRANSACTION: any of the following stockholder-approved
transactions to which the Corporation is a party:

               a. a merger or consolidation in which the Corporation is not the
          surviving entity, except for a transaction the principal purpose of
          which is to change the State in which the Corporation is incorporated,

               b. the sale, transfer or other disposition of all or
          substantially all of the assets of the Corporation in complete
          liquidation or dissolution of the Corporation, or

               c. any reverse merger in which the Corporation is the surviving
          entity but in which securities possessing fifty percent (50%) or more
          of the total combined voting power of the Corporation's outstanding
          securities are transferred to person or persons different from those
          who held such securities immediately prior to such merger.

          EFFECTIVE DATE: September 14, 1993, the date on which the Plan was
adopted by the Board. This restatement of the Plan has an effective date of
February 20, 1998, the date of adoption by the Board, but such restatement is
subject to stockholder approval at the 1998 Annual Meeting.

          FAIR MARKET VALUE: the Fair Market Value per share of Common Stock
determined in accordance with the following provisions:

               a. If the Common Stock is not at the time listed or admitted to
          trading on any national stock exchange but is traded on the Nasdaq
          National Market, the Fair Market Value shall be the closing selling
          price per share on the date in question, as such price is reported by
          the National Association of Securities Dealers on the Nasdaq National
          Market. If there is no reported closing selling price for the Common
          Stock on the date in question, then the closing selling price on the
          last preceding date for which such quotation exists shall be
          determinative of Fair Market Value.

               b. If the Common Stock is at the time listed or admitted to
          trading on any national stock exchange, then the Fair Market Value
          shall be the closing selling price per share on the date in question
          on the exchange determined by the Plan Administrator to be the primary
          market for the Common Stock, as such price is officially quoted in the
          composite tape of transactions on such exchange. If there is no
          reported sale of Common Stock on such exchange on the date in
          question, then the Fair Market Value shall be the closing selling
          price on the exchange on the last preceding date for which such
          quotation exists.



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

          1934 ACT: the Securities Exchange Act of 1934, as amended.

          OPTIONEE: any person to whom an option is granted under the Plan.

          PERMANENT DISABILITY OR PERMANENTLY DISABLED: the inability of the
Optionee to engage in any substantial gainful activity by reason of any
medically determinable physical or mental impairment expected to result in death
or to be of continuous duration of twelve (12) months or more.

          SERVICE: the performance of services as a member of the Board.

          TAKE-OVER PRICE: the greater of (a) the Fair Market Value per share of
Common Stock on the date the option is surrendered to the Corporation in
connection with a Hostile TakeOver or (b) the highest reported price per share
of Common Stock paid by the tender offeror in effecting such Hostile Take-Over.

     III. ADMINISTRATION OF THE PLAN

          The terms and conditions of each automatic option grant (including the
timing and pricing of the option grant) shall be determined by the express terms
and conditions of the Plan, and neither the Board nor any committee of the Board
shall exercise any discretionary functions with respect to option grants made
pursuant to the Plan.

     IV. STOCK SUBJECT TO THE PLAN

          A. Shares of the Corporation's Common Stock shall be available for
issuance under the Plan and shall be drawn from either the Corporation's
authorized but unissued shares of Common Stock or from reacquired shares of
Common Stock, including shares repurchased by the Corporation on the open
market. The maximum number of shares of Common Stock which may be issued over
the term of the Plan shall not exceed 370,000 shares(1), subject to adjustment
from time to time in accordance with the provisions of this Article IV.

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(1)  Includes the 120,000-share increase authorized by the Board on February 20,
     1998, subject to stockholder approval at the 1998 Annual Meeting.



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          B. Should one or more outstanding options under this Plan expire or
terminate for any reason prior to exercise in full, then the shares subject to
the portion of each option not so exercised shall be available for subsequent
option grants under the Plan. Unvested shares issued under the Plan and
subsequently repurchased by the Corporation, at the option exercise price paid
per share, pursuant to the Corporation's repurchase rights under the Plan, shall
be added back to the number of shares of Common Stock reserved for issuance
under the Plan and shall accordingly be available for reissuance through one or
more subsequent option grants under the Plan. Shares subject to any option or
portion thereof surrendered in accordance with Article VII shall reduce on a
share-for-share basis the number of shares of Common Stock available for
subsequent option grants under the Plan. In addition, should the exercise price
of an outstanding option under the Plan be paid with shares of Common Stock,
then the number of shares of Common Stock available for issuance under the Plan
shall be reduced by the gross number of shares for which the option is
exercised, and not by the net number of shares of Common Stock actually issued
to the option holder.

          C. Should any change be made to the Common Stock issuable under the
Plan by reason of any stock split, stock dividend, recapitalization, combination
of shares, exchange of shares or other change affecting the outstanding Common
Stock as a class without the Corporation's receipt of consideration, then
appropriate adjustments shall be made to (i) the maximum number and/or class of
securities issuable under the Plan, (ii) the number and/or class of securities
for which automatic option grants are to be subsequently made per each newly-
elected or continuing non-employee Board member under the Plan, and (iii) the
number and/or class of securities and price per share in effect under each
option outstanding under the Plan. Such adjustments to the outstanding options
are to be effected in a manner which shall preclude the enlargement or dilution
of rights and benefits under such options. The adjustments determined by the
Board shall be final, binding and conclusive.

     V. ELIGIBILITY

          A. Eligible Optionees. The individuals eligible to receive automatic
option grants pursuant to the provisions of this Plan shall be limited to (i)
those individuals who are first elected or appointed as non-employee Board
members after the Effective Date, whether through appointment by the Board or
election by the Corporation's stockholders, and (ii) those individuals who
continue to serve as non-employee Board members after such Effective Date,
whether or not they commenced Board service prior to such Effective Date. In no
event, however, shall any non-employee Board member be eligible to participate
in the Plan if such individual has previously been in the employ of the
Corporation (or any parent or subsidiary corporation) at any time after December
31, 1989. Each non-employee Board member eligible to participate in the Plan
pursuant to the foregoing criteria shall be designated an Eligible Director for
purposes of the Plan.



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     VI. TERMS AND CONDITIONS OF AUTOMATIC OPTION GRANTS

          A. Grant Date. Option grants shall be made on the dates specified
below:

               - Each individual who is first elected or appointed as an
          Eligible Director, whether through appointment by the Board or
          election by the Corporation's stockholders, after the Effective Date
          shall automatically be granted, on the date of such initial election
          or appointment, a non-statutory stock option to purchase 17,500 shares
          of Common Stock.

               - On the first Nasdaq trading day in January of each calendar
          year (commencing with the 1994 calendar year), each individual who is
          at the time serving as an Eligible Director shall automatically be
          granted on such date a non-statutory option to purchase 5,000 shares
          of Common Stock, provided such individual has served as a Board member
          for a period of at least six (6) months.

          There shall be no limit on the number of 5,000-share option grants any
one Eligible Director may receive over his or her period of Board service.

          Stockholder approval of this February 20, 1998 restatement at the 1998
Annual Meeting shall constitute pre-approval of each option grant subsequently
made pursuant to the provisions of the Plan and the subsequent exercise of that
option in accordance with its terms.

          B. Exercise Price. The exercise price per share of Common Stock
subject to each automatic option grant shall be equal to one hundred percent
(100%) of the Fair Market Value per share of Common Stock on the automatic grant
date.

          C. Payment.

               The exercise price shall become immediately due upon exercise of
the option and shall be payable in one of the alternative forms specified below:

                         (i) full payment in cash or check made payable to the
                    Corporation's order; or

                         (ii) full payment in shares of Common Stock held for
                    the requisite period necessary to avoid a charge to the
                    Corporation's earnings for financial-reporting purposes and
                    valued at Fair Market Value on the Exercise Date (as such
                    term is defined below); or

                         (iii) full payment in a combination of shares of Common
                    Stock held for the requisite period necessary to avoid a
                    charge to the Corporation's earnings for financial-reporting
                    purposes and valued at Fair Market Value on the Exercise
                    Date and cash or check payable to the Corporation's order;
                    or



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                         (iv) to the extent the option is exercised for vested
                    shares, full payment through a broker-dealer sale and
                    remittance procedure pursuant to which the non-employee
                    Board member (I) shall provide irrevocable instructions to a
                    Corporation-designated brokerage firm to effect the
                    immediate sale of the purchased shares and remit to the
                    Corporation, out of the sale proceeds available on the
                    settlement date, sufficient funds to cover the aggregate
                    exercise price payable for the purchased shares and (II)
                    shall concurrently provide directives to the Corporation to
                    deliver the certificates for the purchased shares directly
                    to such brokerage firm in order to complete the sale
                    transaction.

          For purposes of this subparagraph VI.C, the Exercise Date shall be the
date on which written notice of the option exercise is delivered to the
Corporation. Except to the extent the sale and remittance procedure specified
above is utilized in connection with the exercise of the option for vested
shares, payment of the option price for the purchased shares must accompany the
exercise notice. However, if the option is exercised for any unvested shares,
then the optionee must also execute and deliver to the Corporation a stock
purchase agreement for those unvested shares which provides the Corporation with
the right to repurchase, at the exercise price paid per share, any unvested
shares held by the optionee at the time of cessation of Board service and which
precludes the sale, transfer or other disposition of any shares purchased under
the option, to the extent those shares are subject to the Corporation's
repurchase right.

          D. Option Term. Each automatic grant under the Plan shall have a
maximum term of ten (10) years measured from the automatic grant date.

          E. Exercisability/Vesting. Each automatic grant shall be immediately
exercisable for any or all of the option shares. However, any shares purchased
under the option shall be subject to repurchase by the Corporation, at the
exercise price paid per share, upon the Optionee's cessation of Board service
prior to vesting in those shares. Each initial 17,500 share option shall vest,
and the Corporation's repurchase right shall lapse, in a series of four (4)
equal and successive annual installments over the Optionee's period of continued
service as a Board member, with the first such installment to vest upon
Optionee's completion of one (1) year of Board service measured from the grant
date. Each additional 5,000-share automatic grant shall vest, and the
Corporation's repurchase with respect thereto shall lapse, upon Optionee's
completion of one (1) year of Board service measured from the automatic grant
date. Vesting of the option shares shall be subject to acceleration as provided
in Section VI.G and Article VII. In no event, however, shall any additional
option shares vest after the Optionee's cessation of Board service.

          F. Non-Transferability. During the lifetime of the Optionee, each
automatic option grant, together with the limited stock appreciation right
pertaining to such option, shall be exercisable only by the Optionee and shall
not be assignable or transferable by the Optionee other than (i) a transfer of
the option effected by will or by the laws of descent and distribution following
Optionee's death or (ii) a transfer of the option during the optionee's lifetime
to one or more members of the optionee's immediate family or to a trust
established exclusively for one



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or more such family members, to the extent such transfer is effected pursuant to
the optionee's estate plan. The assigned portion may only be exercised by the
person or persons who acquire a proprietary interest in the option pursuant to
the assignment. The terms applicable to the assigned portion shall be the same
as those in effect for the option immediately prior to such assignment and shall
be set forth in such documents issued to the assignee as the Corporation may
deem appropriate.

          G. Effect of Termination of Board Service.

               1. Should the Optionee cease to serve as a Board member for any
reason (other than death or Permanent Disability) while holding one or more
automatic option grants under the Plan, then such individual shall have a six
(6)-month period following the date of such cessation of Board service in which
to exercise each such option for any or all of the option shares in which the
Optionee is vested at the time of such cessation of Board service. Each such
option shall immediately terminate and cease to be outstanding, at the time of
such cessation of Board service, with respect to any option shares in which the
Optionee is not otherwise at that time vested.

               2. Should the Optionee die within six (6) months after cessation
of Board service, then any automatic option grant held by the Optionee at the
time of death may subsequently be exercised, for any or all of the option shares
in which the Optionee is vested at the time of his or her cessation of Board
service (less any option shares subsequently purchased by the Optionee prior to
death), by the personal representative of the Optionee's estate or by the person
or persons to whom the option is transferred pursuant to the Optionee's will or
in accordance with the laws of descent and distribution. The right to exercise
each such option shall lapse upon the expiration of the twelve (12)-month period
measured from after the date of the Optionee's death.

               3. Should the Optionee die or become Permanent Disabled while
serving as a Board member, then the shares of Common Stock at the time subject
to each automatic option grant held by such Optionee shall immediately vest in
full (and the Corporation's repurchase right with respect to such shares shall
terminate), and the Optionee (or the representative of the Optionee's estate or
the person or persons to whom the option is transferred upon the Optionee's
death) shall have a twelve (12)-month period following the date of the
Optionee's cessation of Board service in which to exercise such option for any
or all of those vested shares of Common Stock.

               4. In no event shall any automatic grant under this Plan remain
exercisable after the expiration date of the ten (10)-year option term. Upon the
expiration of the applicable post-service exercise period under subparagraphs 1
through 3 above or (if earlier) upon the expiration of the ten (10)-year option
term, the automatic grant shall terminate and cease to be outstanding for any
option shares in which the Optionee was vested at the time of his or her
cessation of Board service but for which such option was not otherwise
exercised.



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          H. Stockholder Rights. The holder of an automatic option grant shall
have none of the rights of a stockholder with respect to any shares subject to
such option until such individual shall have exercised the option and paid the
exercise price for the purchased shares.

          I. Remaining Terms. The remaining terms and conditions of each
automatic option grant shall be as set forth in the form Non-statutory Stock
Option Agreement attached as Exhibit A.

     VII. CORPORATE TRANSACTION/CHANGE IN CONTROL/HOSTILE TAKE-OVER

          A. In the event of any Corporate Transaction, the shares of Common
Stock at the time subject to each outstanding option but not otherwise vested
shall automatically vest in full so that each such option shall, immediately
prior to the specified effective date for the Corporate Transaction, become
fully exercisable for all of the shares of Common Stock at the time subject to
that option and may be exercised for all or any portion of such shares as fully-
vested shares of Common Stock. Immediately following the consummation of the
Corporate Transaction, each automatic option grant under the Plan shall
terminate and cease to be outstanding, except to the extent assumed by the
successor entity (or parent thereof).

          B. In connection with any Change in Control of the Corporation, the
shares of Common Stock at the time subject to each outstanding option but not
otherwise vested shall automatically vest in full so that each such option
shall, immediately prior to the specified effective date for the Change in
Control, become fully exercisable for all of the shares of Common Stock at the
time subject to that option and may be exercised for all or any portion of such
shares as fully-vested shares of Common Stock. Each such option shall remain
fully exercisable for the option shares which vest in connection with the Change
in Control until the expiration or sooner termination of the option term.

          C. The Optionee shall have the right, exercisable at any time within
the thirty (30)-day period immediately following the effective date of a Hostile
Take-Over, to surrender to the Corporation each automatic option grant held by
him or her under this Plan. The Optionee shall in return be entitled to a cash
distribution from the Corporation in an amount equal to the excess of (i) the
Take-Over Price of the shares of Common Stock at the time subject to the
surrendered option (whether or not the Optionee is otherwise at the time vested
in those shares) over (ii) the aggregate exercise price payable for such shares.
Such cash distribution shall be paid within five (5) days following the
surrender of the option to the Corporation. Stockholder approval of this
February 20, 1998 restatement at the 1998 Annual Meeting shall constitute the
pre-approval of each option subsequently granted with such a surrender right and
the subsequent exercise of that right in accordance with the provisions of this
Section VII.C. Neither the approval of the Plan Administrator nor the consent of
the Board shall be required at the time of the actual option surrender and cash
distribution.



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          D. The shares of Common Stock subject to each option surrendered in
connection with the Hostile Take-Over shall NOT be available for subsequent
option grant under this Plan.

          E. The automatic option grants outstanding under the Plan shall in no
way affect the right of the Corporation to adjust, reclassify, reorganize or
otherwise change its capital or business structure or to merge, consolidate,
dissolve, liquidate or sell or transfer all or any part of its business or
assets.

     VIII. AMENDMENT OF THE PLAN AND AWARDS

          The Board has complete and exclusive power and authority to amend or
modify the Plan (or any component thereof) in any or all respects whatsoever.
However, no such amendment or modification shall adversely affect rights and
obligations with respect to options at the time outstanding under the Plan,
unless the affected optionees consent to such amendment. In addition, certain
amendments to the Plan may require stockholder approval pursuant to applicable
law or regulation.

     IX. EFFECTIVE DATE AND TERM OF PLAN

          A. The Plan became effective immediately upon adoption by the Board on
September 14, 1993 and was approved by the Corporation's stockholders at the
1994 Annual Meeting. On January 25, 1995, the Board adopted an amendment to the
Plan which increased the number of shares of Common Stock issuable thereunder by
an additional 100,000 shares, and that amendment was approved by the
stockholders at the 1995 Annual Meeting.

          B. On February 20, 1998, the Board adopted a series of amendments to
the Plan (the "1998 Amendments") which (i) increased the number of shares of
Common Stock reserved for issuance over the term of the Plan by an additional
120,000 shares, (ii) allowed unvested shares issued under the Plan and
subsequently repurchased by the Corporation at the option exercise price paid
per share to be reissued under the Plan and (iii) effected a series of
additional changes to the provisions of the Plan (including the stockholder
approval requirements, the transferability of non-statutory stock options and
the elimination of the six (6)-month holding period requirement as a condition
to the exercise of stock appreciation rights) in order to take advantage of the
recent amendments to Rule 16b-3 of the 1934 Act which exempts certain
transactions by Board members under the Plan from the short-swing liability
provisions of the federal securities laws. The 1998 Amendments were approved by
the stockholders at the 1998 Annual Meeting.

          C. The Plan shall terminate upon the earlier of (i) September 13, 2003
or (ii) the date on which all shares available for issuance under the Plan shall
have been issued as vested shares or cancelled pursuant to the cash-out
provisions of the Plan. If the date of termination is determined under clause
(i) above, then all option grants outstanding on such date shall thereafter



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continue to have force and effect in accordance with the provisions of the
instruments evidencing such grants.

     X. USE OF PROCEEDS

          Any cash proceeds received by the Corporation from the sale of shares
pursuant to option grants or share issuances under the Plan shall be used for
general corporate purposes

     XI. REGULATORY APPROVALS

          A. The implementation of the Plan, the granting of any option under
the Plan and the issuance of Common Stock upon the exercise of the option grants
made hereunder shall be subject to the Corporation's procurement of all
approvals and permits required by regulatory authorities having jurisdiction
over the Plan, the options granted under it, and the Common Stock issued
pursuant to it.

          B. No shares of Common Stock or other assets shall be issued or
delivered under this Plan unless and until there shall have been compliance with
all applicable requirements of Federal and state securities laws, including the
filing and effectiveness of the Form S-8 registration statement for the shares
of Common Stock issuable under the Plan, and all applicable listing requirements
of any securities exchange on which the Common Stock is then listed for trading.

     XII. NO IMPAIRMENT OF RIGHTS

          Neither the action of the Corporation in establishing the Plan nor any
provision of the Plan shall be construed or interpreted so as to affect
adversely or otherwise impair the right of the Corporation or the stockholders
to remove any individual from the Board at any time in accordance with the
provisions of applicable law.

     XIII. MISCELLANEOUS PROVISIONS

          A. The right to acquire Common Stock or other assets under the Plan
may not be assigned, encumbered or otherwise transferred by any Optionee.

          B. The provisions of the Plan relating to the exercise of options and
the vesting of shares shall be governed by the laws of the State of California,
as such laws are applied to contracts entered into and performed in such State.

          C. The provisions of the Plan shall inure to the benefit of, and be
binding upon, the Corporation and its successors or assigns, whether by
Corporate Transaction or otherwise, and the Optionees, the legal representatives
of their respective estates, their respective heirs or legatees and their
permitted assignees.



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