1997 INCENTIVE AND NON-INCENTIVE

                        STOCK OPTION PLAN

                                OF

                    CISTRON BIOTECHNOLOGY, INC.

                (Amended as of December 27, 1999)


        1. Purpose of Plan.
           ----------------
           The purpose of this Incentive and Non-Incentive Stock
Option Plan ("Plan") is to further the growth and development of
Cistron Biotechnology, 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. [Intentionally Omitted].

        3. Stock Subject to the Plan.
           --------------------------
           An aggregate of 1,200,000 shares of the Company's
Common Stock, $.01 par value ("Common Stock") subject, however,
to adjustment or change pursuant to paragraph 13 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, as the
Board of Directors ("Board") shall from time to time determine,
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.

        4. Administration.
           ---------------
           The Plan shall be administered by the Board, which
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 all or any portion
of the Options shall be incentive stock options ("Incentive
Options") qualifying under Section 422 of the Code or stock
options which do not so qualify ("Non-Incentive Options");
whether each Option shall have a "cashless-exercise" provision;
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 pursuant to Section 10 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 Board 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 Board in its sole discretion may deem relevant.
Subject to the express provisions of the Plan, the Board shall
also have authority to interpret the Plan; to prescribe, amend
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.

        5. 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
424(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
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
employee of the Company is 400,000 shares.

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

        6. Option Price.

           The purchase price of the shares of Common Stock under
each Option shall be determined by the Board, 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 85% 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 Board determines
otherwise, the "fair market value" of a share of Common Stock as
of a certain date shall be the closing bid price of the Common
Stock on The Nasdaq Stock Market (or the Nasdaq Electronic
Bulletin Board) or, if the Common Stock is not then traded on
The Nasdaq Stock Market (or quoted on the Nasdaq Electronic
Bulletin Board), such national securities exchange on which the
Common Stock is then traded, on the trading date immediately
preceding the date the fair market value is being determined.
The Board 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 Board shall by resolution
duly authorize such Option.

        7. Term of Options.

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

        8. Exercise of Options.

           Each Option shall be exercisable to the extent
determined by the Board, but in no event shall an Option be
exercisable until at least six months from the date of grant.

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

           (b) Except as provided in paragraphs 9, 10 and 11
hereof, and unless determined otherwise by the Board 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.

           (c) 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 Board may, in its discretion, include
a "cashless exercise" provision in the applicable Option
Agreement, in which event the optionee will be permitted 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, provided such shares, if
purchased upon exercise of a stock option, shall have been held
for at least six months.

           (d) 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.

           (e) 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.

        9. 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
Board may provide in the Option Agreement for transferability of
a Non-Incentive Option to an optionee's family members or family
trusts.

        10. 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 other
than death, 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 Board, the
exercisability of an outstanding Non-Incentive Option may be
extended to a date determined by the Board but not beyond ten
years from the date of grant.

            (b) The Board 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.

        11. Disability of Holder of Option.

            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.

        12. 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.

        13. 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 other-wise, 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 Board whose determination
thereon shall be conclusive.

        14. Acceleration of Exercisability Upon Change in Control.

            Except as otherwise provided in a specific grant of
Options, 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, during any period of
two consecutive years or less, of individuals who at the
beginning of such period constituted a majority of the Board,
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.

        15. Vesting of Rights Under Options.

            Neither anything contained in the Plan nor in any
resolution adopted or to be adopted by the Board 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.

        16. Withholding Taxes.

            The Company shall have the right to require the
recipient to remit to the Company an amount sufficient to
satisfy any federal, state and local withholding tax
requirements in connection with any grant made hereunder.

        17. Termination and Amendment.

            The Plan, which was adopted by the Board on November
4, 1997 and is subject to stockholder approval, shall terminate
on November 3, 2007 and no Option shall be granted under the
Plan after such date.  The Board may at any time prior to such
date terminate the Plan or make such modifications or amendments
thereto as it shall deem advisable; provided, however, that
stockholder approval shall be required if otherwise required to
comply with the Code, the listed company requirements of The
Nasdaq Stock Market or of a national securities exchange on
which the Common Stock is then traded, or other applicable
provisions of state or federal law or self-regulatory agencies;
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.


                        EXHIBIT A

                CISTRON BIOTECHNOLOGY, INC.

              INCENTIVE STOCK OPTION AGREEMENT



To:

        We are pleased to notify you that by the determination
of the Board of Directors (herein called the "Board") an
incentive stock option to purchase _______ shares of the Common
Stock of Cistron Biotechnology, Inc. (herein called the
"Company") at a price of $______ per share has this __ day of
_______ been granted to you under the Company's 1997 Incentive
and Non-Incentive Stock Option Plan (herein called the "Plan").
This option may be exercised only upon the terms and conditions
set forth below.

        1. Purpose of Option.

           The purpose of the Plan under which this incentive
stock option has been granted is to further the growth and
development of the Company and its subsidiaries by encouraging
key employees, directors, consultants, agents, independent
contractors 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. Acceptance of Option Agreement.

           Your execution of this incentive stock option
agreement will indicate your acceptance of and your willingness
to be bound by its terms; it imposes no obligation upon you to
purchase any of the shares subject to this option.  Your
obligation to purchase shares can arise only upon your exercise
of the option in the manner set forth in paragraph 4 hereof.

        3. When Option May Be Exercised.

           (a)  The option granted you hereunder may not be
exercised for a period of six months from the date of its grant
by the Board as set forth above.  Thereafter, this option shall
be exercisable as follows:

[Insert exercisability provisions. A typical example,
although not required under the Plan, is as follows:]

        [(i)    at the end of one year from the date of
                grant, up to 25% of the total shares subject
                to the option;

        (ii)    at the end of the second year from the date
                of grant, up to 50%;

        (iii)   at the end of the third year from the
                date of grant, up to 75%;

        (iv)    at the end of the fourth year from the date
                of grant, up to 100%.]

        This option may not be exercised for less than ten shares at any
one time (or the remaining shares then purchasable if less than
ten) and expires at the end of ________ years [insert number of
years; maximum - ten years] from the date of grant whether or
not it has been duly exercised (hereinafter, the "Option
Expiration Date"), unless sooner terminated as provided in
paragraphs 5, 6 or 7 hereof.

        4. How Option May Be Exercised.

           This option is exercisable by a written notice signed
by you and delivered to the Company at its executive offices,
signifying your election to exercise the option.  The notice
must state the number of shares of Common Stock as to which your
option is being exercised, must contain a statement by you (in a
form acceptable to the Company) that such shares are being
acquired by you for investment and not with a view to their
distribution or resale (unless a Registration Statement covering
the shares purchasable has been declared effective by the
Securities and Exchange Commission) and must be accompanied by
cash or a check to the order of the Company for the full
purchase price of the shares being purchased [if "cashless
exercise" is permitted, add the following phrase:] [, unless
exercised pursuant to the following "cashless exercise"
provision.]

  	[Insert the following "cashless exercise" provision,
if granted by the Board:] [In lieu of paying for the shares
purchasable under this option by cash or check, you may deliver
previously owned shares of Common Stock with a fair market value
equal to the full purchase price of the shares being purchased
under this option, provided if such shares have been issued upon
exercise of an option, they have been held for at least six
months.]

         If notice of the exercise of this option is given by a
person or persons other than you, the Company may require, as a
condition to the exercise of this option, the submission to the
Company of appropriate proof of the right of such person or
persons to exercise this option.

         Certificates for shares of the Common Stock so
purchased will be issued as soon as practicable. The Company,
however, shall not be required to issue or deliver a certificate
for any shares until it has complied with all requirements of
the Securities Act of 1933, the Securities Exchange Act of 1934,
any stock exchange on which the Company's Common Stock may then
be listed and all applicable state laws in connection with the
issuance or sale of such shares or the listing of such shares on
said exchange.  Until the issuance of the certification for such
shares, you or such other person as may be entitled to exercise
this option shall have none of the rights of a stockholder with
respect to shares subject to this option.

         The Company shall have the right to require you, or
such other person as may be permitted to exercise this option,
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 shares of Common
Stock issuable upon exercise of this option.

        5. Termination of Employment.

           If your employment with the Company (or a subsidiary
thereof) is terminated for any reason other than by death or
disability, you may exercise, within three months from the date
of such termination, that portion of the option which was
exercisable by you at the date of such termination, provided,
however, that such exercise occurs no later than the Option
Expiration Date.

        6. Disability.

           If your employment with the Company (or a subsidiary
thereof) is terminated by reason of your disability, you may
exercise, within twelve months from the date of such
termination, that portion of this option which was exercisable
by you at the date of such termination, provided, however, that
such exercise occurs no later than the Option Expiration Date.

        7. Death.

           If you die while employed by the Company (or a
subsidiary thereof) or within six months after termination of
your employment due to disability, that portion of this option
which was exercisable by you at the date of your death may be
exercised by your legatee or legatees under your Will, or by
your personal representatives or distributees, within twelve
months from the date of your death, but in no event after the
Option Expiration Date.

        8. Non-Transferability of Option.

           This option shall not be transferable except by Will
or the laws of descent and distribution, and may be exercised
during your lifetime only by you.

        9. Adjustments upon Changes in Capitalization.

           If at any time after the date of grant of this 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
this option and the price of each such share shall be
proportionately adjusted for any such change by the Board, whose
determination shall be conclusive.

       10. Acceleration of Exercisability Upon Change in Control.

        [Can be changed if desired] Upon the occurrence of a
"change in control" of the Company (as defined below), this
option shall become immediately fully exercisable.  For purposes
of this option, 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, during any period of
two consecutive years or less, of individuals who at the
beginning of such period constituted a majority of the Board,
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.

       11. Subject to Terms of the Plan.

           This incentive stock option agreement shall be subject
in all respects to the terms and conditions of the Plan and in
the event of any question or controversy relating to the terms
of the Plan, the decision of the Board shall be conclusive.

                                  Sincerely yours,

                                  CISTRON BIOTECHNOLOGY, INC.



                             By:  _____________________________
                           Name:
                          Title:

Agreed to and accepted this
__day of ______, 199_.

______________________
Signature of Optionee


                                EXHIBIT B

                        CISTRON BIOTECHNOLOGY, INC.

                  NON-INCENTIVE STOCK OPTION AGREEMENT



To:

        We are pleased to notify you that by the determination
of the Board of Directors (herein called the "Board") a non-
incentive stock option to purchase ______ shares of the Common
Stock of Cistron Biotechnology, Inc. (herein called the
"Company") at a price of $______ per share has this day of
_________ been granted to you under the Company's 1997 Incentive
and Non-Incentive Stock Option Plan (herein called the "Plan").
This option may be exercised only upon the terms and conditions
set forth below.

        1. Purpose of Option.

           The purpose of the Plan under which this non-incentive
stock option has been granted is to further the growth and
development of the Company and its subsidiaries by encouraging
key employees, directors, consultants, agents, independent
contractors 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. Acceptance of Option Agreement.

           Your execution of this non-incentive stock option
agreement will indicate your acceptance of and your willingness
to be bound by its terms; it imposes no obligation upon you to
purchase any of the shares subject to this option.  Your
obligation to purchase shares can arise only upon your exercise
of the option in the manner set forth in paragraph 4 hereof.

        3. When Option May Be Exercised.

           The option granted you hereunder shall be exercisable
as follows:  [set forth terms and expiration date of Option, but
in no event shall the Option be exercisable until at least six
months from the date of grant].

           This option may not be exercised for less than ten
shares at any one time (or the remaining shares then purchasable
if less than ten) and expires at the end of ________ years
[insert number of years; maximum - ten years] from the date of
grant whether or not it has been duly exercised (hereinafter,
the "Option Expiration Date"), unless sooner terminated as
provided in paragraphs 5, 6 or 7 hereof.

        4. How Option May Be Exercised.

           This option is exercisable by a written notice signed
by you and delivered to the Company at its executive offices,
signifying your election to exercise the option.  The notice
must state the number of shares of Common Stock as to which your
option is being exercised, must contain a statement by you (in a
form acceptable to the Company) that such shares are being
acquired by you for investment and not with a view to their
distribution or resale (unless a Registration Statement covering
the shares purchased has been declared effective by the
Securities and Exchange Commission) and must be accompanied by
cash or a check to the order of the Company for the full
purchase price of the shares being purchased, plus such amount,
if any, as is required for withholding taxes. [If "cashless
exercise" is permitted, add the following phrase:]
[Notwithstanding the foregoing, this option may also be
exercised pursuant to the following "cashless exercise"
provision.]

        [Insert the following "cashless exercise" provision,
if granted by the Board:] [In lieu of paying for the shares
purchasable under this option by cash or check, you may deliver
previously owned shares of Common Stock with a fair market value
equal to the full purchase price of the shares being purchased
under this option, provided if such shares have been issued upon
exercise of an option, you have held such shares for at least
six months.]

        If notice of the exercise of this option is given by a
person or persons other than you, the Company may require, as a
condition to the exercise of this option, the submission to the
Company of appropriate proof of the right of such person or
persons to exercise this option.

        Certificates for shares of the Common Stock so
purchased will be issued as soon as practicable.  The Company,
however, shall not be required to issue or deliver a certificate
for any shares until it has complied with all requirements of
the Securities Act of 1933, the Securities Exchange Act of 1934,
any stock exchange on which the Company's Common Stock may then
be listed and all applicable state laws in connection with the
issuance or sale of such shares or the listing of such shares on
said exchange.  Until the issuance of the certificate for such
shares, you or such other person as may be entitled to exercise
this option shall have none of the rights of a stockholder with
respect to shares subject to this option.

        The Company shall have the right to require you, or
such other person as may be permitted to exercise this option,
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 shares of Common
Stock issuable upon exercise of this option.

        5. Termination of Employment or Engagement.

        [The Board may determine to delete this provision, at
the time of grant or by amendment, to a non-employee, in which
event the words "Intentionally omitted" should be inserted.]  If
your employment with the Company (or a subsidiary thereof) is
terminated for any reason other than by death or disability, or
if a you are not an employee of the Company and your engagement
by the Company (or a subsidiary) is terminated for any reason
other than death, you may exercise, within three months from the
date of such termination, that portion of this option which was
exercisable by you at the date of such termination, provided,
however, that such exercise occurs prior to the Option
Expiration Date.

        6. Disability.

           If your employment with the Company (or a subsidiary
thereof) is terminated by reason of your disability, you may
exercise, within twelve months from the date of such
termination, that portion of this option which was exercisable
by you at the date of such termination, provided, however, that
such exercise occurs prior to the Option Expiration Date.

        7. Death.

           If you die while employed by, or while performing
services for, the Company (or a subsidiary thereof) or within
six months after termination of your employment due to
disability, that portion of this option which was exercisable by
you at the date of your death may be exercised by your legatee
or legatees under your Will, or by your personal representatives
or distributees, within twelve months from the date of your
death, but in no event after the Option Expiration Date.

        8. Non-Transferability of Option.

           This option shall not be transferable except by Will
or the laws of descent and distribution, and may be exercised
during your lifetime only by you.

        [Alternative Section 8, if provided for by the Board:]

        [Limited Transferability of Option. This option shall
not be transferable except to members of your family or to your
family trust(s), and by Will or the laws of descent and
distribution.]

        9. Adjustments upon Changes in Capitalization.

           If at any time after the date of grant of this 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
this option and the price of each such share shall be
proportionately adjusted for any such change by the Board, whose
determination shall be conclusive.

       10. Acceleration of Exercisability Upon Change in Control.

           [can be changed if desired.]  Upon the occurrence of a
"change in control" of the Company (as defined below), this
option shall become immediately fully exercisable.  For purposes
of this option, 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, during any period of
two consecutive years or less, of individuals who at the
beginning of such period constituted a majority of the Board,
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.

       11. Subject to Terms of the Plan.

           This non-incentive stock option agreement shall be
subject in all respects to the terms and conditions of the Plan
and in the event of any question or controversy relating to the
terms of the Plan, the decision of the Board shall be
conclusive.

       12. Tax Status.

           This option does not qualify as an "incentive stock
option" under the provisions of Section 422 of the Internal
Revenue Code of 1986, as amended, and the income tax
implications of your receipt of a non-incentive stock option and
your exercise of such an option should be discussed with your
tax counsel.

                                    Sincerely yours,

                                CISTRON BIOTECHNOLOGY, INC.



                            By:  _____________________________
                          Name:
                         Title:

Agreed to and accepted this
__ day of ______, 199_.


______________________
Signature of Optionee