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                                                                Exhibit 10.23

                                 IMMUNEX CORPORATION

                                1993 STOCK OPTION PLAN
                     AS AMENDED AND RESTATED ON FEBRUARY 13, 1997

                                 SECTION 1.  PURPOSE
The purpose of the Amended and Restated 1993 Stock Option Plan (this "Plan") is
to provide a means whereby selected employees, directors and officers of Immunex
Corporation (the "Company"), or of any parent or subsidiary (as defined in
subsection 5.8 and referred to hereinafter as "related corporations") thereof,
may be granted incentive stock options and/or nonqualified stock options to
purchase the Common Stock (as defined in Section 3) of the Company, in order to
attract and retain the services or advice of such employees, directors and
officers and to provide added incentive to such persons by encouraging stock
ownership in the Company.

                              Section 2.  Administration
This Plan shall be administered by a Stock Option Plan Administration Committee
(the "Committee" or "Plan Administrator") appointed by the Board of Directors of
the Company (the "Board") consisting of two or more members of the Board. If and
so long as the Common Stock is registered under Section 12(b) or 12(g) of the
Securities Exchange Act of 1934, as amended from time to time (the "Exchange
Act"), the Board shall consider in selecting the Plan Administrator and the
membership of any committee acting as Plan Administrator of the Plan with
respect to any persons subject or likely to become subject to Section 16 under
the Exchange Act the provisions regarding (a) "outside directors" as
contemplated by Section 162(m) of the Internal Revenue Code of 1986, as amended
(the "Code"), and (b) "nonemployee directors" as contemplated by Rule 16b-3
under the Exchange Act.  The Board may delegate the responsibility for
administering the Plan with respect to designated classes of eligible
Participants to different committees, subject to such limitations as the Board
deems appropriate.  Committee members shall serve for such term as the Board may
determine, subject to removal by the Board at any time.
2.1 Procedures
The Board shall designate one of the members of the Plan Administrator as
chairman.  The Plan Administrator may hold meetings at such times and places as
it shall determine.  The acts of a majority of the members of the Plan
Administrator present at meetings at which a quorum exists, or acts reduced to
or approved in writing by all Plan Administrator members, shall be valid acts of
the Plan Administrator.
2.2 Responsibilities
Except for the terms and conditions explicitly set forth in this Plan, the Plan
Administrator shall have the authority, in its discretion, to determine all
matters relating to the options to be granted under this Plan, including
selection of the individuals to be granted options, the number of shares to be
subject to each option, the exercise price, and all other terms and conditions
of the options.  Grants under this Plan need not be identical in any respect,
even when made simultaneously.  The interpretation and construction by the Plan
Administrator of any terms or provisions of this Plan or any option issued
hereunder, or of any rule or regulation promulgated in connection herewith,
shall be conclusive and binding on all interested parties, so long as such
interpretation and construction with respect to incentive stock options
correspond to the requirements of Section 422 of the Code, the regulations
thereunder and any amendments thereto.


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2.3 Section 16(b) Compliance and Bifurcation of Plan
Notwithstanding anything in this Plan to the contrary, the Board, in its
absolute discretion, may bifurcate this Plan so as to restrict, limit or
condition the use of any provision of this Plan to participants who are officers
and directors subject to Section 16 of the Exchange Act without so restricting,
limiting or conditioning this Plan with respect to other participants.

                        Section 3.  Stock Subject to This Plan
The stock subject to this Plan shall be the Company's Common Stock, par value
$.01.01 per share (the "Common Stock"), presently authorized but unissued. 
Subject to adjustment as provided in Section 7, the aggregate amount of Common
Stock to be delivered upon the exercise of all options granted under this Plan
shall not exceed 6,225,267 shares.  If any option granted under this Plan shall
expire or be surrendered, exchanged for another option, cancelled or terminated
for any reason without having been exercised in full, the unpurchased shares
subject thereto shall thereupon again be available for purposes of this Plan,
including for replacement options which may be granted in exchange for such
expired, surrendered, exchanged, cancelled or terminated options.

                               Section 4.  Eligibility
An incentive stock option may be granted only to an individual who, at the time
the option is granted, is an employee of the Company or any related corporation.
A nonqualified stock option may be granted to any employee, director or officer
of the Company or any related corporation, whether an individual or an entity. 
Any party to whom an option is granted under this Plan shall be referred to
hereinafter as an "Optionee."

                     Section 5.  Terms and Conditions of Options
Options granted under this Plan shall be evidenced by written agreements which
shall contain such terms, conditions, limitations and restrictions as the Plan
Administrator shall deem advisable and which are not inconsistent with this
Plan.  Notwithstanding the foregoing, options shall include or incorporate by
reference the following terms and conditions:
5.1 Number of Shares and Price
The maximum number of shares that may be purchased pursuant to the exercise of
each option and the price per share at which such option is exercisable (the
"exercise price") shall be as established by the Plan Administrator; provided,
however, that the maximum number of shares with respect to which an option or
options may be granted to any Optionee in any one fiscal year of the Company
shall not exceed 200,000 shares (the "Maximum Annual Optionee Grant"); however,
the Company may make additional one-time grants of up to 200,000 shares to newly
hired employees, provided further that the Plan Administrator shall act in good
faith to establish the exercise price which shall be not less than the fair
market value per share of the Common Stock at the time the option is granted
with respect to incentive stock options and not less than the par value per
share of the Common Stock at the time the option is granted with respect to
nonqualified stock options and also provided that, with respect to incentive
stock options granted to greater than 10% shareholders, the exercise price shall
be as required by subsection 6.1.


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5.2 Term and Maturity
Subject to the restrictions contained in Section 6 with respect to granting
incentive stock options to greater than 10% shareholders, the term of each
incentive stock option shall be as established by the Plan Administrator and, if
not so established, shall be 10 years from the date it is granted but in no
event shall it exceed 10 years.  The term of each nonqualified stock option
shall be as established by the Plan Administrator and, if not so established,
shall be 10 years.  To ensure that the Company or related corporation will
achieve the purpose and receive the benefits contemplated in this Plan, any
option granted to any Optionee hereunder shall, unless the condition of this
sentence is waived or modified in the agreement evidencing the option or by
resolution adopted at any time by the Plan Administrator, be exercisable
according to the following schedule:

<TABLE>
<CAPTION>

    Period of Optionee's Continuous Relationship           Portion of Total Option Which Is Exercisable
    With the Company or Related Corporation From
         the Date the Option Is Granted
    
<S>             <C>                                                           <C>
                 after one year                                               20%

                  after two years                                             40%

                 after three years                                             60%

                after four years                                               80%

                after five years                                             100%

</TABLE>
5.3 Exercise
Subject to the vesting schedule described in subsection 5.2, each option may be
exercised in whole or in part at any time and from time to time; provided,
however, that no fewer than 20% of the shares purchasable under the option (or
the remaining shares then purchasable under the option, if less than 20%) may be
purchased upon any exercise of option rights hereunder and that only whole
shares will be issued pursuant to the exercise of any option and that the
exercise price shall not be less than the par value per share of the Common
Stock at the time the option is exercised.  During an Optionee's lifetime, any
options granted under this Plan are personal to him or her and are exercisable
solely by such Optionee.  Options shall be exercised by delivery to the Company
of notice of the number of shares with respect to which the option is exercised,
together with payment of the exercise price.
5.4 Payment of Exercise Price
Payment of the option exercise price shall be made in full at the time the
notice of exercise of the option is delivered to the Company and shall be in
cash, bank certified or cashier's check or personal check (unless at the time of
exercise the Plan Administrator in a particular case determines not to accept a
personal check) for the Common Stock being purchased.
The Plan Administrator can determine at any time before exercise that additional
forms of payment will be permitted.  To the extent permitted by applicable laws
and regulations (including, but not limited to, federal tax and securities laws
and regulations and state corporate law), and unless the Plan Administrator
determines otherwise, an option also may be exercised, either singly or in
combination with one or more of the alternative forms of payment authorized by
this Section 5.4 by:
    (a)  tendering (either actually or by attestation) shares of stock of the
Company held by an Optionee having a fair market value equal to the exercise
price, such fair market value to be determined in good faith by the Plan
Administrator; provided, however, that payment in stock held by an Optionee
shall not be made unless the stock shall have been owned by the Optionee for a
period of at least six months (or any shorter period necessary to avoid a charge
to the Company's earnings for financial accounting purposes); or
    (b)  delivery of a properly executed exercise notice, together with
irrevocable instructions to a broker, all in accordance with the regulations of
the Federal Reserve Board, to promptly deliver to the Company the amount of sale
or loan proceeds to pay the exercise price and any federal, state or local
withholding tax obligations that may arise in connection with the exercise.
In addition, the exercise price for shares purchased under an option may be
paid, either singly or in combination with one or more of the alternative forms
of payment authorized by this Section 5.4, by (y) delivery of a full-recourse
promissory note executed by the Optionee; provided that (i) such note delivered
in connection with an incentive stock option shall, and such note delivered in
connection with a nonqualified stock option may, in the sole discretion of the
Plan Administrator, bear interest at a rate specified by the Plan Administrator
but in no case less than the rate required to avoid imputation of interest
(taking into account any exceptions to the imputed interest rules) for federal
income tax purposes, (ii) the Plan Administrator


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in its sole discretion shall specify the term and other provisions of such note
at the time an incentive stock option is granted or at any time prior to
exercise of a nonqualified stock option, (iii) the Plan Administrator may
require that the Optionee pledge to the Company for the purpose of securing the
payment of such note the shares of Common Stock to be issued to the Optionee
upon exercise of the option and may require that the certificate representing
such shares be held in escrow in order to perfect the Company's security
interest, and (iv) the Plan Administrator in its sole discretion may at any time
restrict or rescind this right upon notification to the Optionee; or (z) such
other consideration as the Plan Administrator may permit.  
5.5 Withholding Tax Requirement
The Company or any related corporation shall have the right to retain and
withhold from any payment of cash or Common Stock under this Plan the amount of
taxes required by any government to be withheld or otherwise deducted and paid
with respect to such payment.  At its discretion, the Company may require an
Optionee receiving shares of Common Stock to reimburse the Company for any such
taxes required to be withheld by the Company and withhold any distribution in
whole or in part until the Company is so reimbursed.  In lieu thereof, the
Company shall have the right to withhold from any other cash amounts due or to
become due from the Company to the Optionee an amount equal to such taxes.  The
Company may also retain and withhold or the Optionee may elect, subject to
approval by the Company at its sole discretion, to have the Company retain and
withhold a number of shares having a market value not less than the amount of
such taxes required to be withheld by the Company to reimburse the Company for
any such taxes and cancel (in whole or in part) any such shares so withheld.
5.6 Holding Periods

         5.6.1     Securities Exchange Act Section 16
If an individual subject to Section 16 of the Exchange Act sells shares of
Common Stock obtained upon the exercise of a stock option within six 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.
         5.6.2     Taxation of Stock Options
The Plan Administrator may require an Optionee to give the Company prompt notice
of any disposition of shares of Common Stock acquired by the exercise of an
incentive stock option prior to the expiration of two years after the date of
grant of the option and one year from the date of exercise.
5.7 Nontransferability of Options
Options granted under this Plan and the rights and privileges conferred hereby
may not be transferred, assigned, pledged or hypothecated in any manner (whether
by operation of law or otherwise, other than by will or by the applicable laws
of descent and distribution and shall not be subject to execution, attachment or
similar process.  Any attempt to transfer, assign, pledge, hypothecate or
otherwise dispose of any option under this Plan or of any right or privilege
conferred hereby, contrary to the Code or to the provisions of this Plan, or the
sale or levy or any attachment or similar process upon the rights and privileges
conferred hereby shall be null and void.  Notwithstanding the foregoing, if the
Company permits, an Optionee may, 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 Plan Administrator.  Such designation may be
changed from time to time by the Optionee by giving written notice to the Plan
Administrator revoking any earlier designation and making a new designation.
5.8 Termination of Relationship
If the Optionee's relationship with the Company or any related corporation
ceases for any reason other than termination for cause, death or total
disability, and unless by its terms the option sooner terminates or expires,
then the portion of the option which is not exercisable at the time of such
cessation shall terminate immediately upon such cessation, unless the Plan
Administrator determines otherwise, and the Optionee may exercise, for a
three-month period, that portion of the option which is exercisable at the time
of such cessation, and shall terminate at the end of such period following such
cessation as to all shares for which it has not theretofore been exercised,
unless the Plan Administrator determines otherwise.  The Plan Administrator
shall have sole discretion in a particular circumstance to extend the exercise
period following such cessation to any date up to the termination or expiration
of the option.  If, however, in the case of an incentive stock option, the
Optionee does not exercise the Optionee's option within three months after
cessation of employment, the option will no longer qualify as an incentive stock
option under the Code.
If an Optionee is terminated for cause, any option granted hereunder shall
automatically terminate as of the first discovery by the Company of any reason
for termination for cause, and such Optionee shall thereupon have no right to
purchase any shares pursuant to such option.  "Termination for cause" shall mean
dismissal for dishonesty, conviction or confession of a crime punishable by law
(except minor violations), fraud, misconduct or disclosure of confidential
information.

If an Optionee's relationship with the Company or any related corporation is
suspended pending an investigation of whether or not the Optionee shall be
terminated for cause, all the Optionee's rights under any option granted
hereunder likewise shall be suspended during the period of investigation.
If an Optionee's relationship with the Company or any related corporation ceases
because of a total disability, the portion of the Optionee's option that is
exercisable at the time of such cessation shall not terminate or, in the case of
an incentive stock option, cease to be treated as an incentive stock option
until the end of the 12-month period following such cessation (unless


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by its terms it sooner terminates and expires).  As used in this Plan, the term
"total disability" refers to a mental or physical impairment of the Optionee
which is expected to result in death or which has lasted or is expected to last
for a continuous period of 12 months or more and which causes the Optionee to be
unable, in the opinion of the Company and two independent physicians, to perform
his or her duties for the Company and to be engaged in any substantial gainful
activity.  Total disability shall be deemed to have occurred on the first day
after the Company and the two independent physicians have furnished their
opinion of total disability to the Plan Administrator.
Options granted under this Plan shall not be affected by any change of
relationship with the Company so long as the Optionee continues to be an
employee, director, officer, agent, consultant, advisor or independent
contractor of the Company or of a related corporation.  The Plan Administrator,
in its absolute discretion, may determine all questions of whether particular
leaves of absence constitute a termination of services; provided, however, that
with respect to incentive stock options, such determination shall be subject to
any requirements contained in the Code.  The foregoing notwithstanding, with
respect to incentive stock options, employment shall not be deemed to continue
beyond the first 90 days of such leave, unless the Optionee's reemployment
rights are guaranteed by statute or by contract.
As used herein, the term "related corporation," when referring to a subsidiary
corporation, shall mean any corporation (other than the Company) in, at the time
of the granting of the option, an unbroken chain of corporations ending with the
Company, if stock possessing 50% or more of the total combined voting power of
all classes of stock of each of the corporations other than the Company is owned
by one of the other corporations in such chain.  When referring to a parent
corporation, the term "related corporation" shall mean any corporation in an
unbroken chain of corporations ending with the Company if, at the time of the
granting of the option, each of the corporations other than the Company owns
stock possessing 50% or more of the total combined voting power of all classes
of stock in one of the other corporations in such chain.
5.9 Death of Optionee
If an Optionee dies while he or she has a relationship with the Company or any
related corporation or within the three-month period (or 12-month period in the
case of totally disabled Optionees) following cessation of such relationship,
any option held by such Optionee to the extent that the Optionee would have been
entitled to exercise such option, may be exercised within one year after his or
her death by the personal representative of his or her estate or by the person
or persons to whom the Optionee's rights under the option shall pass by will or
by the applicable laws of descent and distribution.
5.10     No Status As Shareholder
Neither the Optionee nor any party to which the Optionee's rights and privileges
under the option may pass shall be, or have any of the rights or privileges of,
a shareholder of the Company with respect to any of the shares issuable upon the
exercise of any option granted under this Plan unless and until such option has
been exercised.
5.11     Continuation of Relationship
Nothing in this Plan or in any option granted pursuant to this Plan shall confer
upon any Optionee any right to continue in the employ or other relationship of
the Company or of a related corporation, or to interfere in any way with the
right of the Company or of any such related corporation to terminate his or her
employment or other relationship with the Company at any time.
5.12     Modification and Amendment of Option
Subject to the requirements of Section 422 of the Code with respect to incentive
stock options and to the terms and conditions and within the limitations of this
Plan, the Plan Administrator may modify or amend outstanding options granted
under this Plan.  The modification or amendment of an outstanding option shall
not, without the consent of the Optionee, impair or diminish any of his or her
rights or any of the obligations of the Company under such option.  Except as
otherwise provided in this Plan, no outstanding option shall be terminated
without the consent of the Optionee.  Unless the Optionee agrees otherwise, any
changes or adjustments made to outstanding incentive stock options granted under
this Plan shall be made in such a manner so as not to constitute a
"modification" as defined in Section 424(h) of the Code and so as not to cause
any incentive stock option issued hereunder to fail to continue to qualify as an
incentive stock option as defined in Section 422(b) of the Code.
5.13     Limitation on Value for Incentive Stock Options
As to all incentive stock options granted under the terms of this Plan, to the
extent that the aggregate fair market value of the stock (determined at the time
the incentive stock option is granted) with respect to which incentive stock
options are exercisable for the first time by the Optionee during any calendar
year (under this Plan and all other incentive stock option plans of the Company,
a related corporation or a predecessor corporation) exceeds $100,000, such
options shall be treated as nonqualified stock options.  The previous sentence
shall not apply if the Internal Revenue Service issues a statutory change,
public rule, issues a private ruling to the Company, any Optionee or any
legatee, personal representative or distributee of an Optionee or issues
regulations changing or eliminating such annual limit.


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                      Section 6.  Greater Than 10% Shareholders
6.1 Exercise Price and Term of Incentive Stock Options
If incentive stock options are granted under this Plan to employees who own more
than 10% of the total combined voting power of all classes of stock of the
Company or any related corporation, the term of such incentive stock options
shall not exceed five years and the exercise price shall be not less than 110%
of the fair market value of the Common Stock at the time the incentive stock
option is granted.  This provision shall control notwithstanding any contrary
terms contained in an option agreement or any other document.
6.2 Attribution Rule
For purposes of subsection 6.1, in determining stock ownership, an employee
shall be deemed to own the stock owned, directly or indirectly, by or for his or
her brothers, sisters, spouse, ancestors and lineal descendants.  Stock owned,
directly or indirectly, by or for a corporation, partnership, estate or trust
shall be deemed to be owned proportionately by or for its shareholders, partners
or beneficiaries.  If an employee or a person related to the employee owns an
unexercised option or warrant to purchase stock of the Company, the stock
subject to that portion of the option or warrant which is unexercised shall not
be counted in determining stock ownership.  For purposes of this Section 6,
stock owned by an employee shall include all stock actually issued and
outstanding immediately before the grant of the incentive stock option to the
employee.

                Section 7.  Adjustments Upon Changes in Capitalization
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 Common Stock resulting from a split-up or consolidation of shares or
any like capital adjustment, or the payment of any stock dividend.
7.1 Effect of Liquidation or Reorganization
    7.1.1  Cash, Stock or Other Property for Stock
Except as provided in subsection 7.1.2, upon a merger (other than a merger of
the Company in which the holders of 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 Company, as a result
of which the shareholders of the Company receive cash, stock or other property
in exchange for or in connection with their shares of Common Stock, any option
granted hereunder shall terminate, but the Optionee shall have the right
immediately prior to any such merger, consolidation, acquisition of property or
stock, liquidation or reorganization 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.
    7.1.2  Conversion of Options on Stock for Stock Exchange
If the shareholders of the Company receive capital stock of another corporation
("Exchange Stock") in exchange for their shares of Common Stock in any
transaction involving a merger (other than a merger of the Company in which the
holders of 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, liquidation
or reorganization (other than a mere reincorporation or the creation of a
holding company), the Company and the corporation issuing the Exchange Stock, in
their sole discretion, may determine that all options granted hereunder shall be
converted into options to purchase shares of Exchange Stock instead of
terminating in accordance with the provisions of subsection 7.1.1.  The amount
and price of converted options shall be determined by adjusting the amount and
price of the options granted hereunder in the same proportion as used for
determining the number of shares of Exchange Stock the holders of the Common
Stock receive in such merger, consolidation, acquisition of property or stock,
liquidation or reorganization.  Unless accelerated by the Board, the vesting
schedule set forth in the option agreement shall continue to apply to the
options granted for the Exchange Stock.
7.2 Fractional Shares
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.
7.3 Determination of Board to Be Final
All Section 7 adjustments shall be made by the Plan Administrator, and its
determination as to what adjustments shall be made, and the extent thereof,
shall be final, binding and conclusive.  Unless an Optionee agrees otherwise,
any change or adjustment to an incentive stock option shall be made in such a
manner so as not to constitute a "modification" as defined in Section 424(h) of
the Code and so as not to cause his or her incentive stock option issued
hereunder to fail to continue to qualify as an incentive stock option as defined
in Section 422(b) of the Code.


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                          Section 8.  Securities Regulation
Shares shall not be issued with respect to an option granted under this Plan
unless the exercise of such option and the issuance and delivery of such shares
pursuant thereto shall comply with all relevant provisions of law, including,
without limitation, any applicable state securities laws, the Securities Act of
1933, as amended, the Exchange Act, the rules and regulations promulgated
thereunder, and the requirements of any stock exchange upon which the shares may
then be listed, and shall be further subject to the approval of counsel for the
Company with respect to such compliance, including the availability, if
applicable of an exemption from registration for the issuance and sale of any
shares hereunder.  

                        Section 9.  Amendment and Termination
9.1 Board Action
The Board may at any time suspend, amend or terminate this Plan, provided that
except as set forth in Section 7, and to the extent required for compliance with
Section 422 of the Code or Section 162(m) of the Code or by any applicable law
or requirement, the Company's shareholders must approve within 12 months of the
adoption by the Board any amendment which will:
    (a)  increase the total number of shares that may be issued under this
Plan;
    (b)  modify the class of participants eligible for participation in this
Plan; or
    (c)  otherwise require stockholder approval under any applicable law or
regulation.
Any amendment made to this Plan since its original adoption which would
constitute a "modification" to incentive stock options outstanding on the date
of such amendment, shall not be applicable to such outstanding incentive stock
options, but shall have prospective effect only, unless the Optionee agrees
otherwise.
9.2 Automatic Termination
Unless sooner terminated by the Board, this Plan shall terminate ten years from
the earlier of (a) the date on which this Plan is adopted by the Board or
(b) the date on which this Plan is approved by the shareholders of the Company. 
No option may be granted after such termination or during any suspension of this
Plan.  The amendment or termination of this Plan shall not, without the consent
of the Optionee, impair or diminish any rights or obligations under any option
theretofore granted under this Plan.

                       Section 10.  Effectiveness of This Plan
This Plan shall become effective upon adoption by the Board so long as it is
approved by a majority of stock represented by shareholders voting either in
person or by proxy at a duly held shareholders' meeting any time within 12
months before or after the adoption of this Plan.
Plan adopted by the Board of Directors on March 11, 1993 and approved by the
sole stockholder on March 11, 1993.  Ratified by Board of Directors on June 1,
1993.  Amended on July 14, 1993.  Amendment and Restatement to increase number
of shares issuable approved by the Board of Directors on February 2, 1995 and by
stockholders on April 26, 1995.  Amended and Restated by Board of Directors on
February 13, 1997.


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