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      EX-99.1
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             STOCK OPTION PLAN


                                                                  EXHIBIT 99.1
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                             2000 STOCK OPTION PLAN
                                       OF
                       AMERICAN BIOGENETIC SCIENCES, INC.

     1. PURPOSES OF THE PLAN. This stock option plan (the "Plan") is designed to
provide an incentive to employees (including directors and officers who are
employees) and to consultants who are not employees of American Biogenetic
Sciences, Inc., a Delaware corporation (the "Company"), and its present and
future subsidiary corporations, as defined in Paragraph 19 ("Subsidiaries"), and
to offer an additional inducement in obtaining the services of such employees
and consultants. The Plan provides for the grant of "incentive stock options"
("ISOs") within the meaning of Section 422 of the Internal Revenue Code of 1986,
as amended (the "Code"), and nonqualified stock options which do not qualify as
ISOs ("NQSOs"), but the Company makes no representation or warranty, express or
implied, as to the qualification of any option as an "incentive stock option"
under the Code.

     2. STOCK SUBJECT TO THE PLAN. Subject to the provisions of Paragraph 12,
the aggregate number of shares of Class A Common Stock, $.001 par value per
share, of the Company ("Common Stock") for which options may be granted under
the Plan shall not exceed 3,000,000. Such shares of Common Stock may, in the
discretion of the Board of Directors of the Company (the "Board of Directors"),
consist either in whole or in part of authorized but unissued shares of Common
Stock or shares of Common Stock held in the treasury of the Company. Subject to
the provisions of Paragraph 13, any shares of Common Stock subject to an option
which for any reason expires, is canceled or is terminated unexercised or which

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ceases for any reason to be exercisable shall again become available for the
granting of options under the Plan. The Company shall at all times during the
term of the Plan reserve and keep available such number of shares of Common
Stock as will be sufficient to satisfy the requirements of the Plan.

     3. ADMINISTRATION OF THE PLAN. The Plan shall be administered by the Board
of Directors or, to the extent the Board of Directors may determine, a committee
of the Board of Directors (the "Committee") consisting of not less than two
directors, each of whom shall be a "non-employee director" within the meaning of
Rule 16b-3 (or any successor rule or regulation) promulgated under the
Securities Exchange Act of 1934, as amended (as the same may be in effect and
interpreted from time to time, "Rule 16b-3"). A majority of the members of the
Committee shall constitute a quorum, and the acts of a majority of the members
present at any meeting at which a quorum is present, and any acts approved in
writing by all members without a meeting, shall be the acts of the Committee.
All references in the Plan to determinations or actions of the Committee shall
be deemed to include determinations and actions by the Committee or the Board of
Directors.

     Subject to the express provisions of the Plan, the Committee shall have the
authority, in its sole discretion, to determine the employees and the
consultants who shall be granted options; the times when options shall be
granted; whether an option granted to an employee shall be an ISO or a NQSO; the
number of shares of Common Stock to be subject to each option; the term of each
option; the date each option shall become exercisable; whether an option shall
be exercisable in whole, in part or in installments and, if in installments, the
number of shares of Common Stock to be subject to each installment, whether the
installments shall be cumulative, the date each installment shall become
exercisable and the term of each installment; whether to accelerate the date of
exercise of any option or installment; whether shares of Common Stock may be
issued upon the exercise of an option as partly paid and, if so, the dates when
future installments of the exercise price shall become due and the amounts of
such installments; the exercise price of each option; the form of payment of the
exercise price; the fair market value of a share of Common Stock; whether to
restrict the sale or other disposition of the shares of Common Stock acquired
upon the exercise of an option and, if so, whether to waive any such
restriction; whether to subject the exercise of all or any portion of an option
to the fulfillment of contingencies as specified in the contract referred to in
Paragraph 11 (the "Contract"), including without limitation, contingencies
relating to entering into a covenant not to compete with the Company, any of its
Subsidiaries or a Parent (as defined in Paragraph 19), to financial objectives
for the Company, any of its Subsidiaries or a Parent, a division of any of the
foregoing, a product line or other category, and/or the period of continued
employment of the optionee with the Company, any of its Subsidiaries or a
Parent, and to determine whether such contingencies have been met; the amount,
if any, necessary to satisfy the Company's obligation to withhold taxes or other
amounts; whether an optionee is Disabled (as defined in Paragraph 19); to
construe the respective Contracts and the Plan; with the consent of the
optionee, to cancel or modify an option, provided such modified provision would
be permitted to be included in an option on the date of modification, and
further, provided, that, in the case of a modification (within the meaning of
Section 424(h) of the Code) of an ISO, such option as modified would be
permitted to be granted on the date of such modification under the terms of the
Plan; to prescribe, amend and rescind rules and regulations relating to the
Plan; and to make all other determinations necessary or advisable for
administering the Plan. Any controversy or claim arising out of or relating to
the Plan, any option granted under the Plan or any Contract shall be determined
unilaterally by the Committee in its sole discretion. The determinations of the
Committee on the matters referred to in this Paragraph 3 shall be conclusive and
binding on the parties. No member or former member of the Committee shall be
liable for any action, failure to act or determination made in good faith with
respect to the Plan or any option hereunder.

     4. ELIGIBILITY. The Committee may from time to time, in its sole
discretion, consistent with the purposes of the Plan, grant options to employees
(including officers and directors who are employees) of, and to consultants to,
the Company or any of its Subsidiaries. Such options granted shall cover such

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number of shares of Common Stock as the Committee may determine in its sole
discretion; provided, however, that the maximum number of shares subject to
options that may be granted to any employee during any calendar year under the
Plan (the "162(m) Maximum") shall not exceed 500,000 shares; and further,
provided, that the aggregate market value (determined at the time the option is
granted in accordance with Paragraph 5) of the shares of Common Stock for which
any eligible employee may be granted ISOs under the Plan or any other plan of
the Company, or of a Parent or a Subsidiary of the Company, which are
exercisable for the first time by such optionee during any calendar year shall
not exceed $100,000. Such limitation shall be applied by taking ISOs into
account in the order in which they were granted. Any option (or the portion
thereof) granted in excess of such amount shall be treated as an NQSO.

     5. EXERCISE PRICE. The exercise price of the shares of Common Stock under
each option shall be determined by the Committee in its sole discretion;
provided, however, the exercise price of an ISO shall not be less than the fair
market value of the Common Stock subject to such option on the date of grant;
and further, provided, that if, at the time an ISO is granted, the optionee owns
(or is deemed to own under Section 424(d) of the Code) stock possessing more
than 10% of the total combined voting power of all classes of stock of the
Company, of any of its Subsidiaries or of a Parent, the exercise price of such
ISO shall not be less than 110% of the fair market value of the Common Stock
subject to such ISO on the date of grant.

     The fair market value of a share of Common Stock on any day shall be (a) if
the principal market for the Common Stock is a national securities exchange, the
average of the highest and lowest sales prices per share of Common Stock on such
day as reported by such exchange or on a composite tape reflecting transactions
on such exchange, (b) if the principal market for the Common Stock is not a
national securities exchange and the Common Stock is quoted on The Nasdaq Stock
Market ("Nasdaq"), (i) if closing bid and asked price information is available
with respect to the Common Stock, the average of the closing bid and asked
prices per share of Common Stock on such day on Nasdaq, or (ii) if such
information is not available, the average of the highest bid and lowest asked
prices per share of Common Stock on such day on Nasdaq, or (c) if the principal
market for the Common Stock is not a national securities exchange and the Common
Stock is not quoted on Nasdaq, the average of the highest bid and lowest asked
prices per share of Common Stock on such day as reported on the OTC Bulletin
Board Service or by National Quotation Bureau, Incorporated or a comparable
service; provided, however, that if clauses (a), (b) and (c) of this Paragraph
are all inapplicable, or if no trades have been made or no quotes are available
for such day, the fair market value of the Common Stock shall be determined by
the Board by any method consistent with applicable regulations adopted by the
Treasury Department relating to stock options.

     6. TERM. The term of each option granted pursuant to the Plan shall be such
term as is established by the Committee, in its sole discretion; provided,
however, that the term of each ISO granted pursuant to the Plan shall be for a
period not exceeding 10 years from the date of grant thereof; and further,
provided, that if, at the time an ISO is granted, the optionee owns (or is
deemed to own under Section 424(d) of the Code) stock possessing more than 10%
of the total combined voting power of all classes of stock of the Company, of
any of its Subsidiaries or of a Parent, the term of the ISO shall be for a
period not exceeding five years from the date of grant. Options shall be subject
to earlier termination as hereinafter provided.

     7. EXERCISE. An option (or any part or installment thereof), to the extent
then exercisable, shall be exercised by giving written notice to the Company at
its principal office stating which option is being exercised, specifying the
number of shares of Common Stock as to which such option is being exercised and
accompanied by payment in full of the aggregate exercise price therefor (or the
amount due on exercise if the Contract permits installment payments) (a) in cash
or by certified check or (b) if the applicable Contract permits, with previously
acquired shares of Common Stock having an aggregate fair market value on the
date of exercise (determined in accordance with Paragraph 5) equal to the
aggregate exercise price of all options being exercised, or with any combination
of cash, certified check or shares of Common

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Stock

     The Committee may, in its sole discretion, permit payment of the exercise
price of an option by delivery by the optionee of a properly executed notice,
together with a copy of the optionee's irrevocable instructions to a broker
acceptable to the Committee to deliver promptly to the Company the amount of
sale or loan proceeds sufficient to pay such exercise price. In connection
therewith, the Company may enter into agreements for coordinated procedures with
one or more brokerage firms.

     A person entitled to receive Common Stock upon the exercise of an option
shall not have the rights of a stockholder with respect to such shares of Common
Stock until the date of issuance of a stock certificate to him for such shares;
provided, however, that until such stock certificate is issued, any optionee
using previously acquired shares of Common Stock in payment of an option
exercise price shall continue to have the rights of a stockholder with respect
to such previously acquired shares.

     In no case may a fraction of a share of Common Stock be purchased or issued
under the Plan.

     8. TERMINATION OF RELATIONSHIP. Except as may otherwise be expressly
provided in the applicable Contract, any optionee whose relationship with the
Company, its Subsidiaries and Parent as an employee or consultant has terminated
for any reason (other than his death or Disability) may exercise such option, to
the extent exercisable on the date of such termination, at any time within three
months after the date of termination, but not thereafter and in no event after
the date the option would otherwise have expired; provided, however, that if
such relationship is terminated either (a) for cause, or (b) without the consent
of the Company, such option shall terminate immediately.

     For the purposes of the Plan, an employment relationship shall be deemed to
exist between an individual and a corporation if, at the time of the
determination, the individual was an employee of such corporation for purposes
of Section 422(a) of the Code. As a result, an individual on military, sick
leave or other bona fide leave of absence shall continue to be considered an
employee for purposes of the Plan during such leave if the period of the leave
does not exceed 90 days, or, if longer, so long as the individual's right to
reemployment with the Company (or a related corporation) is guaranteed either by
statute or by contract. If the period of leave exceeds 90 days and the
individual's right to reemployment is not guaranteed by statute or by contract,
the employment relationship shall be deemed to have terminated on the 31st day
of such leave.

     Notwithstanding the foregoing, except as may otherwise be expressly
provided in the applicable Contract, options granted under the Plan shall not be
affected by any change in the status of the optionee so long as the optionee
continues to be an employee of, or a consultant to, the Company, any of its
Subsidiaries or a Parent (regardless of having changed from one to the other or
having been transferred from one corporation to another).

     Nothing in the Plan or in any option granted under the Plan shall confer on
any optionee any right to continue in the employ of, or as a consultant to, the
Company, its Parent or any of its Subsidiaries, or interfere in any way with any
right of the Company, its Parent or any of its Subsidiaries to terminate the
optionee's relationship at any time for any reason whatsoever without liability
to the Company, its Parent or any of its Subsidiaries.

     9. DEATH OR DISABILITY OF AN OPTIONEE. Except as may otherwise be expressly
provided in the applicable Contract, if an individual optionee dies (a) while he
is an employee of, or a consultant to, the Company, any of its Subsidiaries or a
Parent, (b) within three months after the termination of such relationship
(unless such termination was for cause or without the consent of the Company) or
(c) within one year following the termination of such relationship by reason of
Disability, his option may be exercised, to the extent exercisable on the date
of his death, by his Legal Representative (as defined in Paragraph 19) at any
time within one year after death, but not thereafter and in

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no event after the date the option would otherwise have expired.

     Except as may otherwise be expressly provided in the applicable Contract,
any optionee whose relationship as an employee of, or a consultant to, the
Company, its Parent or any Subsidiary has terminated by reason of Disability may
exercise his option, to the extent exercisable upon the effective date of such
termination, at any time within one year after such date, but not thereafter and
in no event after the date the option would otherwise have expired.

     10. COMPLIANCE WITH SECURITIES LAWS. It is a condition to the exercise of
any option that either (a) a Registration Statement under the Securities Act of
1933, as amended (the "Securities Act"), with respect to the shares of Common
Stock to be issued upon such exercise shall be effective and current at the time
of exercise, or (b) there be an exemption from registration under the Securities
Act for the issuance of the shares of Common Stock upon such exercise. Nothing
herein shall be construed as requiring the Company to register shares subject to
any option under the Securities Act or to keep any Registration Statement
effective or current.

     The Committee may require, in its sole discretion, as a condition to the
exercise of any option that the optionee execute and deliver to the Company his
representations and warranties, in form, substance and scope satisfactory to the
Committee, which the Committee determines are necessary or convenient to
facilitate the perfection of an exemption from the registration requirements of
the Securities Act or other legal requirement, including without limitation that
(a) the shares of Common Stock to be issued upon the exercise of the option are
being acquired by the optionee for his own account, for investment only and not
with a view to the resale or distribution thereof, and (b) any subsequent resale
or distribution of shares of Common Stock by such optionee will be made only
pursuant to (i) a Registration Statement under the Securities Act which is
effective and current with respect to the shares of Common Stock being sold, or
(ii) a specific exemption from the registration requirements of the Securities
Act, but in claiming such exemption, the optionee shall prior to any offer of
sale or sale of such shares of Common Stock provide the Company with a favorable
written opinion of counsel satisfactory to the Company, in form, substance and
scope satisfactory to the Company, as to the applicability of such exemption to
the proposed sale or distribution.

     In addition, if at any time the Committee shall determine, in its sole
discretion, that the listing or qualification of the shares of Common Stock
subject to such option on any securities exchange, Nasdaq or under any
applicable law, or the consent or approval of any governmental regulatory body,
is necessary or desirable as a condition to, or in connection with, the granting
of an option or the issue of shares of Common Stock thereunder, such option may
not be exercised in whole or in part unless such listing, qualification, consent
or approval shall have been effected or obtained free of any conditions not
acceptable to the Committee.

     11. STOCK OPTION CONTRACTS. Each option shall be evidenced by an
appropriate Contract which shall be duly executed by the Company and the
optionee, and shall contain such terms, provisions and conditions not
inconsistent herewith as may be determined by the Committee.

     12. ADJUSTMENTS UPON CHANGES IN COMMON STOCK. Notwithstanding any other
provision of the Plan, in the event of a stock dividend, split-up, combination,
reclassification, recapitalization, spin-off, merger in which the Company is the
surviving corporation, or exchange of shares or the like which results in a
change in the number or kind of those shares of Common Stock which are
outstanding immediately prior to such event, the aggregate number and kind of
shares subject to the Plan, the aggregate number and kind of shares subject to
each outstanding option and the exercise price thereof, and the 162(m) Maximum
shall be appropriately adjusted by the Board of Directors, whose determination
shall be conclusive and binding on all parties. Such adjustment may provide for
the elimination of fractional shares which might otherwise be subject to options
without payment thereto.

     In the event of (a) the liquidation or dissolution of the Company, or (b) a

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merger in which the Company is not the surviving corporation or a consolidation,
any outstanding options shall terminate upon the earliest of any such event,
unless other provision is made therefor in the transaction.

     13. AMENDMENTS AND TERMINATION OF THE PLAN. The Plan was adopted by the
Board of Directors as of March 31, 2000. No option may be granted under the Plan
after March 30, 2010. The Board of Directors, without further approval of the
Company's stockholders, may at any time suspend or terminate the Plan, in whole
or in part, or amend it from time to time in such respects as it may deem
advisable, including, without limitation, in order that ISOs granted hereunder
meet the requirements for "incentive stock options" under the Code, or to comply
with, conform to or adopt the provisions of Section 162(m) of the Code or
Section 16(b) of the Securities Exchange Act of 1934 or any change in applicable
law, regulations, rulings or interpretations of administrative agencies;
provided, however, that no amendment shall be effective without the requisite
prior or subsequent stockholder approval to the extent required by the Code or
Section 16(b). No termination, suspension or amendment of the Plan shall,
without the consent of the holder of an existing and outstanding option affected
thereby, adversely affect his rights under such option. The power of the
Committee to construe and administer any options granted under the Plan prior to
the termination or suspension of the Plan nevertheless shall continue after such
termination or during such suspension.

     14. NON-TRANSFERABILITY OF OPTIONS. No option granted under the Plan shall
be transferable otherwise than by will or the laws of descent and distribution,
and options may be exercised, during the lifetime of the optionee, only by the
optionee or his Legal Representatives. Except to the extent provided above,
options may not be assigned, transferred, pledged, hypothecated or disposed of
in any way (whether by operation of law or otherwise) and shall not be subject
to execution, attachment or similar process, and any such attempted assignment,
transfer, pledge, hypothecation or disposition shall be null and void ab initio
and of no force or effect.

     15. WITHHOLDING TAXES. The Company shall withhold cash in an amount equal
to the amount determined necessary to satisfy the Company's obligation to
withhold Federal, state and local income taxes or other amounts incurred by
reason of the grant or exercise of an option or the disposition of the
underlying shares of Common Stock except to the extent that, with the specific
authorization of the Committee, in the Contract or otherwise, the optionee is
permitted to pay such amounts by (a) the delivery or withholding of shares of
Common Stock having an aggregate fair market value on the exercise date
(determined in accordance with Paragraph 5) or (b) any combination of cash and
such shares. Alternatively, the Company may require the holder to pay to the
Company such amount, in cash, promptly upon demand. The Company shall not be
required to issue any shares of Common Stock pursuant to any such option until
all required payments have been made.

     16. LEGENDS; PAYMENT OF EXPENSES. The Company may endorse such legend or
legends upon the certificates for shares of Common Stock issued upon exercise of
an option under the Plan and may issue such "stop transfer" instructions to its
transfer agent in respect of such shares as it determines, in its discretion, to
be necessary or appropriate to (a) prevent a violation of, or to perfect an
exemption from, the registration requirements of the Securities Act and any
applicable state securities laws, (b) implement the provisions of the Plan or
any agreement between the Company and the optionee with respect to such shares
of Common Stock, or (c) permit the Company to determine the occurrence of a
"disqualifying disposition," as described in Section 421(b) of the Code, of the
shares of Common Stock issued or transferred upon the exercise of an ISO granted
under the Plan.

     The Company shall pay all issuance taxes with respect to the issuance of
shares of Common Stock upon the exercise of an option granted under the Plan, as
well as all fees and expenses incurred by the Company in connection with such
issuance.

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     17. USE OF PROCEEDS. The cash proceeds from the sale of shares of Common
Stock pursuant to the exercise of options under the Plan shall be added to the
general funds of the Company and used for such corporate purposes as the Board
of Directors may determine.

     18. SUBSTITUTIONS AND ASSUMPTIONS OF OPTIONS OF CERTAIN CONSTITUENT
CORPORATIONS. Anything in this Plan to the contrary notwithstanding, the Board
of Directors may, without further approval by the stockholders, substitute new
options for prior options of a Constituent Corporation (as defined in Paragraph
19) or assume the prior options of such Constituent Corporation.

     19. DEFINITIONS. For purposes of the Plan, the following terms shall be
defined as set forth below:

          (a) Constituent Corporation. The term "Constituent Corporation" shall
     mean any corporation which engages with the Company, any of its
     Subsidiaries or a Parent in a transaction to which Section 424(a) of the
     Code applies (or would apply if the option assumed or substituted were an
     ISO), or any Parent or any Subsidiary of such corporation.

          (b) Disability. The term "Disability" shall mean a permanent and total
     disability within the meaning of Section 22(e)(3) of the Code.

          (c) Legal Representative. The term "Legal Representative" shall mean
     the executor, administrator or other person who at the time is entitled by
     law to exercise the rights of a deceased or incapacitated optionee with
     respect to an option granted under the Plan.

          (d) Parent. The term "Parent" shall have the same definition as
     "parent corporation" in Section 424(e) of the Code.

          (e) Subsidiary. The term "Subsidiary" shall have the same definition
     as "subsidiary corporation" in Section 424(f) of the Code.

     20.  GOVERNING LAW; CONSTRUCTION.  The Plan, such options as may be granted
hereunder and all related matters shall be governed by, and construed in
accordance with, the laws of the State of Delaware, without regard to conflict
of law provisions.

     Neither the Plan nor any Contract shall be construed or interpreted with
any presumption against the Company by reason of the Company causing the Plan or
Contract to be drafted. Whenever from the context it appears appropriate, any
term stated in either the singular or plural shall include the singular and
plural, and any term stated in the masculine, feminine or neuter gender shall
include the masculine, feminine and neuter.

     21.  PARTIAL INVALIDITY.  The invalidity, illegality or unenforceability of
any provision in the Plan or any Contract shall not affect the validity,
legality or enforceability of any other provision, all of which shall be valid,
legal and enforceable to the fullest extent permitted by applicable law.

     22. STOCKHOLDER APPROVAL. The Plan shall be subject to approval by a
majority of the votes present in person or by proxy at the next duly held
meeting of the Company's stockholders at which a quorum is present. No options
granted hereunder may be exercised prior to such approval; provided, however,
that the date of grant of any option shall be determined as if the Plan had not
been subject to such approval. Notwithstanding the foregoing, if the Plan is not
approved by a vote of the stockholders of the Company on or before March 30,
2001, the Plan and any options granted hereunder shall terminate.