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                                                                    EXHIBIT 10.3


                             AMENDED AND RESTATED

                       1990 INCENTIVE AND NON-INCENTIVE

                               STOCK OPTION PLAN

                                      OF
                           NEXELL THERAPEUTICS INC.
                  (FORMERLY NAMED VIMRx PHARMACEUTICALS INC.)

       (AS AMENDED THROUGH DECEMBER 31, 2000 AND AS ADJUSTED TO REFLECT
                THE JUNE 15, 2000 1 FOR 4 REVERSE STOCK SPLIT)

1.   Purpose of Plan.

The purpose of this Incentive and Non-Incentive Stock Option Plan ("Plan") is to
further the growth and development of VIMRx Pharmaceuticals Inc. ("Company") and
any subsidiaries thereof by encouraging selected employees, directors and other
persons who contribute and are expected to contribute materially to the
Company's success to obtain a proprietary interest in the Company through the
ownership of stock, thereby providing such persons with an added incentive to
promote the best interests of the Company and affording the Company a means of
attracting to its service persons of outstanding ability.

2.   Stock Subject to the Plan.

An aggregate of 600,000 shares of the Company's Common Stock, $.001 par value
("Common Stock") subject, however, to adjustment or change pursuant to paragraph
12 hereof, shall be reserved for issuance upon the exercise of options which may
be granted from time to time in accordance with the Plan ("Options"). Such
shares may be, in whole or in part, authorized but unissued shares or issued
shares which have been reacquired by the Company. If, for any reason, an Option
shall lapse, expire or terminate without having been exercised in full, the
unpurchased shares covered thereby shall again be available for purposes of the
Plan.

3.   Administration.

                    (a) Except as provided in paragraph (c) below, the Plan
                    shall be administered by the Committee. The Board of
                    Directors shall appoint the Committee from among its
                    members. Such Committee shall be composed of two or more
                    Directors who, to the extent practicable, shall be "outside
                    directors" as defined in regulations under Section 162(m) of
                    the Internal Revenue Code of 1986, as amended (the "Code"),
                    and "non-employee directors" as defined by Regulation
                    240.16b-3 under the Securities Exchange Act of 1934, as
                    amended. Such Committee shall have and may exercise any and
                    all of the powers relating to the administration of the Plan
                    and the grant of Options thereunder as are set forth in
                    subparagraph 3(b) hereof as the Board of Directors shall
                    confer and delegate. The Board of Directors shall have power
                    at any time to fill vacancies in, to change the membership
                    of, or to discharge such Committee. The Committee shall
                    select one of its members as its chairman and shall hold its
                    meetings at such time and at such places as it shall deem
                    advisable. A majority of such Committee shall constitute a
                    quorum and such majority shall determine its action. Any
                    action may be taken without a meeting by written consent of
                    all the members of the Committee. The Committee shall keep
                    minutes of its proceedings and shall report the same to the
                    Board of Directors at the meeting next succeeding.

                    (b) The Committee shall administer the Plan and, subject to
                    the provisions of the Plan, shall have sole authority in its
                    discretion to determine the persons to whom, and the time or
                    times at which, Options shall be granted; the number of
                    shares to be subject to each such Option; the provisions
                    regarding exercisability of each Option; the expiration date
                    of each Option; whether the Option shall contain a "cashless
                    exercise" provision; whether all or any portion of the
                    Options shall be incentive stock options ("Incentive
                    Options") qualifying under Section 422A of the Code or stock
                    options which do not so qualify ("Non-Incentive Options");
                    whether a Non-Incentive Option shall have limited
                    transferability as permitted under the Plan; and whether a
                    Non-Incentive Option granted to a non-employee shall
                    terminate following the non-employee's termination of
                    engagement in performing services for the Company or its
                    subsidiaries pursuant to Section 9 of the Plan. Both
                    Incentive Options and Non-Incentive Options may be granted
                    to the same person at the same time provided each type of
                    Option is clearly designated. In making such determinations,
                    the Committee may take into account the nature of the
                    services rendered by such persons, their present and
                    potential contribution to the Company's success and such
                    other factors as the Committee in its sole discretion may
                    deem relevant. Subject to the express provisions of the
                    Plan, the Committee shall also have authority to interpret
                    the Plan; to prescribe, amend

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                    and rescind rules and regulations relating thereto; to
                    determine the terms and provisions of the respective Option
                    Agreements, which shall be substantially in the forms
                    attached hereto as Exhibit A and Exhibit B; to amend the
                    provisions of outstanding Options to provide for accelerated
                    exercisability or the extension of the expiration date of
                    such Options; and to make all other determinations necessary
                    or advisable for the administration of the Plan, all of
                    which determinations shall be conclusive and not subject to
                    review.

                    (c) The Board of Directors may administer the Plan, in lieu
                    of and with the same powers as the Committee, with respect
                    to any Options granted or to be granted under the Plan,
                    provided that such administration is consistent with the
                    provisions of Section 162(m) of the Code.

4.   Eligibility for Receipt of Options.

                    (a) Incentive Options. Incentive Options may be granted only
                    to employees (including officers) of the Company and/or any
                    of its subsidiaries. A director of the Company or any
                    subsidiary who is not an employee of the Company or of one
                    of its subsidiaries is not eligible to receive Incentive
                    Options under the Plan. Further, Incentive Options may not
                    be granted to any person who, at the time the Incentive
                    Option is granted, owns (or is considered as owning within
                    the meaning of Section 425(d) of the Code) stock possessing
                    more than 10% of the total combined voting power of all
                    classes of stock of the Company or any subsidiary (10%
                    Owner), unless at the time the Incentive Option is granted
                    to the 10% Owner, the option price is at least 110% of the
                    fair market value of the Common Stock subject thereto and
                    such Incentive Option by its terms is not exercisable
                    subsequent to five years from the date of grant. The
                    aggregate fair market value (determined as of the time an
                    Incentive Option is granted) of the shares of the Company's
                    Common Stock initially purchasable upon exercise of an
                    Incentive Option during any calendar year may not exceed
                    $100,000.

                    (b) Non-Incentive Options. Non-Incentive Options may be
                    granted to any employees (including employees who have been
                    granted Incentive Options), directors, consultants, agents,
                    independent contractors and other persons whom the Board of
                    Directors (or Committee) determines will contribute to the
                    Company's success.

                    (c) The maximum number of shares that may be subject to
                    options under this Plan granted during any calendar year to
                    any executive officer of the Company is 200,000 shares.

                    (d) In the event on outstanding Incentive Option or a
                    portion thereof no longer qualifies as an incentive stock
                    option under Section 422A of the Code, such Option or
                    portion thereof, as applicable, thereafter shall be deemed a
                    Non-Incentive Option under the Plan.

5.   Option Price.

The purchase price of the shares of Common Stock under each Option shall be
determined by the Committee, which determination shall be conclusive and not
subject to review, but in no event shall the purchase price be less than 100% of
the fair market value of the Common Stock on the date of grant in the case of
Incentive Options (110% of fair market value in the case of Incentive Options
granted to a 10% Owner) and 50% of the fair market value of the Common Stock on
the date of the grant in the case of Non-Incentive Options.

For purposes of the Plan, unless the Committee determines otherwise, the "fair
market value" of a share of Common Stock as of a certain date shall be the
closing sale price of the Common Stock on The Nasdaq Stock Market or, if the
Common Stock is not then traded on The Nasdaq Stock Market, such national
securities exchange on which the Common Stock is then traded, on the trading
date immediately preceding the date fair market value is being determined. The
Committee may make such other determination of fair market value, based on other
factors, as it shall deem appropriate.

For purposes of the Plan, the date of grant of an Option shall be the date on
which the Committee shall by resolution duly authorize such Option.

6.   Term of Options.

The term of each Option shall be such number of years as the Committee shall
determine, subject to earlier  termination as herein provided, but in no event
more than ten years from the date such Option is granted.

7.       Exercise of Options.

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                    (a) Each Option shall be exercisable to the extent
                    determined by the Committee, but in no event shall an Option
                    be exercisable until at least six months from the date of
                    grant, except as otherwise provided in paragraph 13 herein.

                    (b) An Option may not be exercised for fractional shares of
                    the Company's Common Stock.

                    (c) Except as provided in paragraphs 9, 10 and 11 hereof,
                    and unless determined otherwise by the Committee with
                    respect to Non-Incentive Options granted to non-employees,
                    no Option shall be exercisable unless the holder thereof
                    shall have been an employee, director, consultant, agent,
                    independent contractor or other person employed by or
                    engaged in performing services for the Company and/or a
                    subsidiary continuously from the date of grant to the date
                    of exercise.

                    (d) The exercise of an Option shall be contingent upon
                    receipt from the holder thereof of a written representation
                    that at the time of such exercise it is the optionee's then
                    present intention to acquire the Option shares for
                    investment and not with a view to the distribution or resale
                    thereof (unless a Registration Statement covering the shares
                    purchasable upon exercise of the Options shall have been
                    declared effective by the Securities and Exchange
                    Commission) and upon receipt by the Company of cash, or a
                    check to its order, for the full purchase price of such
                    shares. The Committee may, in its discretion, include a
                    "cashless exercise" provision in the applicable Option
                    Agreement, in which event the optionee will be permitted (i)
                    to deliver previously owned shares of Common Stock with a
                    fair market value equal to the exercise price in payment of
                    the full purchase price of such shares, or (ii) to request
                    that the Company withhold shares of Common Stock issuable
                    upon exercise of such Option with a fair market value equal
                    to the exercise price of the shares being purchased under
                    the Option (thereby reducing the number of shares issuable
                    upon exercise of the Option).

                    (e) The holder of an Option shall have none of the rights of
                    a stockholder with respect to the shares purchasable upon
                    exercise of the Option until a certificate for such shares
                    shall have been issued to the holder upon due exercise of
                    the Option.

                    (f) The proceeds received by the Company upon exercise of an
                    Option shall be added to the Company's working capital and
                    be available for general corporate purposes .

8.   Transferability of Options.

No Option granted pursuant to the Plan shall be transferable otherwise than by
will or the laws of descent or distribution and an Option may be exercised
during the lifetime of the holder only by such holder, provided, however, that
the Committee may provide for transferability of a Non-Incentive Option to an
optionee's family members or family trusts.

9.   Termination of Employment or Engagement.

                    (a) Except as provided in paragraph (b) below, in the event
                    the employment of the holder of an Option shall be
                    terminated by the Company or a subsidiary for any reason
                    other than by reason of death or disability, or the
                    engagement of a non-employee holder of a Non-Incentive
                    Option shall be terminated by the Company or a subsidiary
                    for any reason, such holder may, within three months from
                    the date of such termination, exercise such Option to the
                    extent such Option was exercisable by such holder at the
                    date of such termination. Notwithstanding the foregoing, no
                    Option may be exercised subsequent to the date of its
                    expiration. Absence on leave approved by the employer
                    corporation shall not be considered an interruption of
                    employment for any purpose under the Plan. In addition, at
                    the discretion of the Committee, the exercisability of an
                    outstanding Non-Incentive Option may be extended to a date
                    determined by the Committee but not beyond ten years from
                    the date of grant.

                    (b) The Committee may, in its discretion, at the time of
                    grant or by amending the applicable outstanding Non-
                    Incentive Option, delete the foregoing termination provision
                    with respect to a Non-Incentive Option granted to a non-
                    employee of the Company or its subsidiaries.

                    (c) Nothing in the Plan or in any Option Agreement granted
                    hereunder shall confer upon any Optionholder any right to
                    continue in the employ of the Company or any subsidiary or
                    obligate the Company or any subsidiary to continue the
                    engagement of any Optionholder or interfere in any way with
                    the right of the Company or any such subsidiary to terminate
                    such Optionholder's employment or engagement at any time.

10.  Disability of Holder of Option.

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If the employment of the holder of an Option shall be terminated by reason of
such holder's disability, such holder may, within twelve months from the date of
such termination, exercise such option to the extent such Option was exercisable
by such holder at the date of such termination. Notwithstanding the foregoing,
no Option may be exercised subsequent to the date of its expiration.

11.  Death of Holder of Option.

If the holder of any Option shall die while in the employ of, or while
performing services for, the Company or one or more of its subsidiaries (or
within six months following termination of employment due to disability), the
Option theretofore granted to such person may be exercised, but only to the
extent such Option was exercisable by the holder at the date of death (or, with
respect to employees, the date of termination of employment due to disability)
by the legatee or legatees of such person under such person's Last Will, or by
such person's personal representative or distributees, within twelve months from
the date of death but in no event subsequent to the expiration date of the
Option.

12.  Adjustments Upon Changes in Capitalization.

If at any time after the date of grant of an Option, the Company shall by stock
dividend, split-up, combination, reclassification or exchange, or through merger
or consolidation or otherwise, change its shares of Common Stock into a
different number or kind or class of shares or other securities or property,
then the number of shares covered by such Option and the price per share thereof
shall be proportionately adjusted for any such change by the Committee whose
determination thereon shall be conclusive.

13.  Acceleration of Exercisability Upon Change in Control.

Upon the occurrence of a "change in control" of the Company (as defined below),
all outstanding Options shall become immediately fully exercisable. For purposes
of the Plan, a "change in control" of the Company shall mean (i) the acquisition
at any time by a "person" or "group" (as such terms are used Sections 13(d) and
14(d)(2) of the Exchange Act of beneficial ownership (as defined in Rule 13d-3
under the Exchange Act), directly or indirectly, of securities representing 50%
or more of the combined voting power in the election of directors of the then
outstanding securities of the Company or any successor or the Company; (ii) the
termination of service of directors, for any reason other than death, disability
or retirement from the Board of Directors, during any period of two consecutive
years or less, of individuals who at the beginning of such period constituted a
majority of the Board of Directors, unless the election of or nomination for
election of each new director during such period was approved by a vote of at
least two-thirds of the directors still in office who were directors at the
beginning of the period; (iii) approval by the stockholders of the Company of
any merger, consolidation, or statutory share exchange as a result of which the
Common Stock shall be changed, converted or exchanged (other than a merger,
consolidation or share exchange with a wholly-owned Subsidiary) or liquidation
of the Company or any sale or disposition of 80% or more of the assets or
earning power or the Company; or (iv) approval by the stockholders of the
Company of any merger, consolidation, or statutory share exchange to which the
Company is a party as a result of which the persons who were stockholders
immediately prior to the effective date of the merger, consolidation or share
exchange shall have beneficial ownership of less than 50% of the combined voting
power in the election of directors of the surviving corporation; provided,
however, that no change in control shall be deemed to have occurred if, prior to
such time as a change in control would otherwise be deemed to have occurred, the
Company's Board of Directors deems otherwise.

14.  Vesting of Rights Under Options.

Neither anything contained in the Plan nor in any resolution adopted or to be
adopted by the Committee, the Board of Directors or the stockholders of the
Company shall constitute the vesting of any rights under any Option. The vesting
of such rights shall take place only when a written Option Agreement,
substantially in the form of the Incentive Stock Option Agreement attached
hereto as Exhibit A or the Non-Incentive Stock Option Agreement attached hereto
as Exhibit B, shall be duly executed and delivered by and on behalf of the
Company and the person to whom the Option shall be granted.

15.  Withholding Taxes.

Whenever under the Plan shares are to be issued in satisfaction of the exercise
of Options granted thereunder, the Company shall have the right to require the
recipient to remit to the Company an amount sufficient to satisfy federal, state
and local withholding tax requirements prior to the delivery of any certificate
or certificates for such shares.

16.  Termination and Amendment.

The Plan, which was adopted by the Board of Directors on July 10, 1990 and
approved by the shareholders of the Company, shall terminate on July 9, 2000 and
no Option shall be granted under the Plan after such date. The Board of
Directors may at any

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time prior to such date terminate the Plan or make such modifications or
amendments thereto as it shall deem advisable, provided, however, that
shareholder approval shall be required:

          (i)   to increase the number of shares reserved for issuance under the
          Plan;

          (ii)  to materially increase the benefits accruing to participants
          under the Plan;

          (iii) to materially modify the requirements of eligibility for
          participation in the Plan; or

          (iv)  if otherwise required to comply with the incentive stock option
          provisions of Section 162(m) of the Code or the listed company
          requirements of The Nasdaq Stock Market or of a national securities
          exchange on which the Common Stock is then traded,

and, provided, further, that no modification or amendment shall adversely affect
the rights of a holder of an Option previously granted under the Plan without
such holder's written consent.

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