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Void after 5:00 P.M.                              Common Stock Warrant
New York Time                                     to Purchase 400,000 Shares 
September 3, 2002                                 of Common Stock of Cistron 
                                                  Biotechnology, Inc.    
                                                      No. 4
						  		

                        CISTRON BIOTECHNOLOGY, INC.

                       Common Stock Purchase Warrant
                           __________________

			This Warrant and the shares of Common Stock issuable 
        upon exercise of this Warrant have not been registered under the 
        Securities Act of 1933, as amended (the "Act"), and may not be 
        sold or otherwise disposed of except (a) to a person who, in the 
        opinion of counsel reasonably acceptable to the Company, is a 
        person to whom the securities may be legally transferred without 
        registration and without delivery of a current prospectus under 
        the Act or (b) to a person upon delivery of a prospectus or 
        offering circular then meeting the requirements of the Act relating 
        to such securities and the offering thereof for such sale or 
        disposition.
                                __________________

                                      -1-
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                This certifies that, FOR VALUE RECEIVED, ROBERT NAISMITH,
PH.D., or registered assigns (the "Holder"), is entitled to purchase, subject
to the provisions of this Warrant, from CISTRON BIOTECHNOLOGY, INC., a Delaware
corporation (the "Company"), 400,000 shares of the Company's common stock,
$.01 par value (the "Common Stock"), at a price of $.25 per share, exercisable
at any time prior to 5:00 P.M., New York Time, on September 3, 2002, at which
time this Warrant shall expire and become void.  The Holder is being issued
this Warrant pursuant to an instruction letter from BlueStone Capital Partners,
L.P. ("BlueStone"), which was entitled to said Warrant pursuant to the
consulting agreement dated September 4, 1997 between the Company and Blues-
Stone, as amended, as partial consideration to BlueStone in connection with the
exeuction and delivery of agreements between the Company and PASTEUR MERIEUX
SERUMS & VACCINS, S.A., a societe anonyme organized under the Laws of France
("PMS&V") on the date hereof.  This Warrant is subject to the provisions of a
letter agreement, dated October 29, 1998, between the Company and PMS&V in
which the Company granted PMS&V a priority with respect to the piggyback
registration of its shares over other security holders of the Company who have
piggyback registration rights.  The number of shares of Common Stock to be
received upon exercise of this Warrant and the price to be paid for each share
of Common Stock are subject to possible adjustment from time to time as
hereinafter set forth.  The shares of Common Stock or other securities or
property deliverable upon such exercise as adjusted from time to time are
hereinafter sometimes referred to as the "Warrant Shares" and the exercise
price of a share of Common Stock in effect at any time and as adjusted from
time to time is hereinafter sometimes referred to as the "Exercise Price."
Unless the context otherwise requires, the term "Warrant" as used herein
includes this Warrant and any other warrant or warrants that may be issued
pursuant to the provisions of this Warrant, whether upon transfer, assignment,
partial exercise, divisions, combinations, exchange, or otherwise, and the
term "Holder" includes any transferee or transferees or assignee or assignees
of the Holder named above, all of whom shall be subject to the provisions of
this Warrant, and, when used with reference to Warrant Shares, means the holder
or holders of such Warrant Shares.

        Section 1.      Exercise of Warrant.
                        --------------------

                1.1.    Method of Exercise.  This Warrant may be exercised in
whole or in part, but for not less than 25,000 Warrant Shares or the balance
then exercisable, at any time by the Holder prior to 5:00 P.M., New York Time,
on September 3, 2002 by presentation and surrender hereof to the Company at
its principal office with the Subscription Form annexed hereto, duly executed
and accompanied by payment, by certified or official bank checks payable to
the order of the Company, of the Exercise Price for the total number of
Warrant Shares purchased.

                1.2.    Delivery of Shares.  Upon proper exercise of this
Warrant, the Company promptly shall deliver certificates for the Warrant Shares
to the Holder duly legended as authorized in the Subscription Form.

                                   -2-
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                1.3.  Partial Exercise.  If this Warrant is exercised in part
only, the Company shall, upon presentation of this Warrant upon such exercise,
execute and deliver (with the certificate for the Warrant Shares purchased) a
new Warrant evidencing the rights of the Holder hereof to purchase the balance
of the Warrant Shares purchasable hereunder upon the same terms and conditions
as herein set forth.

                1.4.  Fractional Shares.  No fractional shares or scrip
representing fractional shares shall be issued upon exercise of this Warrant
but, in lieu thereof, the Company shall round up to the next full share. 

        Section 2.      Exercise Price and Adjustments.
                        -------------------------------

                2.1.    Initial Exercise Price and Capital Adjustments.  The
Exercise Price at which the Warrant Shares shall be purchasable shall be $.25
per share, subject to adjustment from time to time in the event of stock
dividends, stock subdivisions, stock splits, or stock combinations, as follows:
In the event the Company shall at any time after the date hereof issue shares
of its Common Stock as a stock dividend or shall subdivide or split or
combine the outstanding shares of its Common Stock, the Exercise Price shall
forthwith proportionately be decreased in the case of a stock dividend, sub-
division, or stock split or proportionately be increased in the case of
combination, to the nearest one cent to give effect to such change.
Concurrently, the number of Warrant Shares issuable upon exercise of this
Warrant shall be increased or decreased in proportion to the increase or
decrease in the number of shares of Common Stock outstanding resulting from
such change.  Any such adjustment shall become effective at the close of
business on the date that the subdivision or combination shall become
effective, in the event of a subdivision or combination, or at the close of
business on the record date fixed for the determination of stockholders
entitled to receipt of the stock dividend, in the event of a stock dividend.  

                2.2.    Reorganizations, Mergers, and Sale of Assets.  In the
event of any reorganization or reclassification of the outstanding shares of
Common Stock (other than a change in par value, or from par value to no par
value, or from no par value to par value, or as a result of a subdivision or
combination) or in the case of any consolidation of the Company with, or
merger of the Company into, another corporation after which no securities of
the Company will be publicly held, or in the case of any sale, lease, or
conveyance of all, or substantially all, of the property, assets, business,
and goodwill of the Company as an entity, the Holder shall thereafter have the
right upon exercise to purchase the kind and amount of shares of stock and
other securities and property receivable upon such reorganization,
reclassification, consolidation, merger, or sale by a holder of the number of
shares of Common Stock that the Holder would have received had he exercised
this Warrant immediately prior to such reorganization, reclassification,
consolidation, merger, or sale, at a price equal to the

                              -3-
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aggregate Exercise Price then in effect pertaining to this Warrant (the kind,
amount, and price of such stock and other securities to be subject to
adjustment as herein provided).

                2.3.    Liquidation and Dissolution.  In the event the Company
shall, at any time prior to the expiration of this Warrant and prior to the
exercise thereof, dissolve, liquidate, or wind up its affairs, the Holder shall
be entitled, upon the exercise thereof, to receive, in lieu of the shares that
he would have been entitled to receive, the same kind and amount of assets as
would have been issued, distributed, or paid to him upon any such dissolution,
liquidation, or winding up with respect to such shares had he been the holder
of record of such shares on the record date for the determination of those
entitled to receive any such liquidating distribution.  After any such
dissolution, liquidation, or winding up that shall result in any cash
distribution in excess of the Exercise Price provided for by this Warrant,
the Holder may, at his option, exercise the same without making payment of the
Exercise Price, and in such case, the Company shall upon the distribution to
the Holder consider that the Exercise Price has been paid in full to it and,
in making settlement to the Holder, shall deduct from the amount payable to
the Holder an amount equal to such Exercise Price.

                2.4.    Amendments Not Required to Reflect Adjustments.  
Irrespective of any adjustments in the Exercise Price or the number or kind
of shares purchasable upon exercise of this Warrant, this Warrant may continue
to express the same price and number and kind of shares as originally issued
and need not be amended to reflect each such adjustment.

        Section 3.      Exchange, Assignment, or Loss of Warrant.

                3.1.    Exchange of Warrant.  This Warrant is exchangeable,
without expense, at the option of the Holder, upon presentation and surrender
hereof to the Company for other Warrants of different denominations entitling
the Holder thereof to purchase in the aggregate the same number of Warrant
Shares purchasable hereunder on the same terms and conditions as herein set
forth.

                3.2.    Assignment of Warrant.  Subject to compliance with
Section 4 hereof, this Warrant may be assigned by presentation and surrender
to the Company at its principal office or at the office of its stock transfer
agent, if any, with the Assignment Form annexed hereto duly executed
accompanied by funds sufficient to pay any transfer tax.  Upon such
presentation and surrender, the Company shall, without charge, execute and
deliver a new Warrant in the name of the assignee named in the Assignment
Form and shall promptly cancel this Warrant.

                3.3.    Loss or Mutilation of Warrant.  Upon receipt by the
Company of evidence satisfactory to it of the loss, theft, destruction, or
mutilation of this Warrant, and (in the case of loss, theft, or destruction)
or reasonably satisfactory indemnification, and upon

                             -4-
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surrender and cancellation of this Warrant, if mutilated, the Company will
execute and deliver a new Warrant of like tenor and date and any such lost,
stolen, or destroyed Warrant shall thereupon become void.  Any such new
Warrant executed and delivered shall constitute an additional contractual
obligation on the part of the Company, whether or not this Warrant so lost,
stolen, destroyed, or mutilated shall be at any time enforceable by anyone.

        Section 4.      Compliance with Securities Act of 1933.
                        ---------------------------------------

                4.1.    Disposition of Warrant and/or Warrant Shares.  This
Warrant and/or the Warrant Shares may not be sold or otherwise disposed of
except as follows:

                        (a)     To a person who, in the opinion of counsel
        reasonably satisfactory to the Company, is a person to whom this
        Warrant or the Warrant Shares may legally be transferred without
        registration and without the delivery of a current prospectus under
        the Act with respect thereto and then only against receipt of an
        agreement of such person to comply with the provisions of this
        Section 4 with respect to any resale or other disposition of such
        securities unless, in the opinion of counsel, such agreement is not
        required; or

                        (b)     To any person upon delivery of a prospectus or
        offering circular then meeting the requirements of the Act relating to
        such securities and the offering thereof for such sale or disposition.

                4.2.    Legending of Certificates.  Each certificate for
Warrant Shares or for any other security issued or issuable upon exercise of
this Warrant shall contain a legend on the face thereof, in form and substance
satisfactory to counsel to the Company, setting forth the restrictions on
transfer thereof contained in this Section 4.

        Section 5.      Registration Rights.
                        --------------------

                5.1.    Demand Registration Rights.  At any time subsequent to
the date hereof and prior to the Termination Date, upon the written request of
the Holders of a majority of the Warrant Shares issuable (or issued) under this
Warrant, the Company shall on one occasion promptly file (notwithstanding that
at the time of the request this Warrant shall not theretofore have been
exercised) and process to effectiveness under the Securities Act of 1933, the
requisite post-effectiveness amendments or new registration statement necessary
to permit the public offering of the Warrant Shares requested to be registered
in such written request and shall keep the final prospectus current for a
period of nine months to permit the public offering to be effected during such
period.  All costs, expenses and fees of such registration shall be paid by
the Company.
                             -5-
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                5.2.    "Piggyback" Registration Rights.  Pursuant to a letter
agreement between BlueStone and the Company, dated October 29, 1998, Bluestone
granted PMS&V a priority with respect to piggyback registration of its shares
over other security holders of the Company who have piggyback registration
rights, including the shares issuable upon exercise of this Warrant.  Subject
to the foregoing, in the event the Company at any time subsequent to the date
hereof and prior to the Termination Date contemplates the filing of a
registration statement under the Securities Act of 1933 on Form S-1, S-2 or
S-3 for the public offering of shares of its Common Stock for its own account,
the Company shall give written notice thereof to the Holder of this Warrant
(and/or the Warrant Shares issued upon exercise hereof) at least 30 days prior
to the anticipated filing date and, upon the written request of such Holder,
will, subject to the consent of the managing underwriter of such offering,
include in such registration statement, at the Company's expense, the number
of Warrant Shares requested.  Nothing in this Section 5.2 shall be deemed to
create any liability on the part of the Company to the Holder if the Company,
at its sole discretion, should decide not to proceed with the processing of
such registration statement after filing and before the registration statement
shall become effective.  The Company shall be under no obligation to the
Holder to keep such registration statement current after completion of the
offering by the underwriters. Any Warrant Shares not sold by the Holder
pursuant to such registration statement shall be de-registered.

                5.3.    Expenses.  The expenses to be paid by the Company in
connection with the registration rights granted in Section 5.2 shall include,
without limitation, the fees and expenses of the Company's counsel and
accountants, the costs and expenses incident to the preparation, printing,
filing and processing to effectiveness of the registration statement, the
costs of furnishing the selling Holder of Warrant Shares with a reasonable
number of copies of the Final Prospectus, and the fees and disbursements
incurred in qualifying the Warrant Shares under applicable blue sky or
securities laws, but shall not include any underwriting discounts or
commissions, stock transfer taxes and fees and expenses of counsel for the
Holder of this Warrant and/or the Warrant Shares issuable upon exercise
hereof.

                5.4.    Information To Be Furnished By Holder.  The Holder
shall furnish in writing to the Company all appropriate information
reasonably requested by the Company concerning such Holder in connection
with the preparation and processing of the requisite registration statement
or post-effective amendments relating to a public offering of the Warrant
Shares, including a shareholder's questionnaire, a warranty as to legal
capacity to sell and a statement as to knowledge of adverse facts relating
to the Company, and shall otherwise cooperate with the Company in connection
therewith.

                5.5.    Indemnification.  The Company shall indemnify and
hold harmless each Holder of Warrant Shares included in any registration
statement or post-effective amendment relating to a public offering of
Warrant Shares and each underwriter,

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within the meaning of the Securities Act of 1933, who may purchase Warrant
Shares from, or sell Warrant Shares on behalf of, any such Holder from and
against any and all losses, claims, damages and liabilities, joint or several,
to which any such person may become subject under the Securities Act of 1933,
or otherwise, caused by, arising out of or based upon any untrue  statement or
alleged untrue statement of a material fact contained in such registration
statement or post-effective amendment or any prospectus included therein, or
caused by, arising out of or based upon the omission or alleged omission to
state therein a material fact required to be stated therein or necessary to
make the statements therein not misleading, and to reimburse each such Holder
and underwriter for any legal or other expenses reasonably incurred in
connection with investigating or defending any such loss, claim, damage,
liability or action, except insofar as such losses, claims, damages or
liabilities arose out of or are based upon any such untrue statement or
alleged untrue statement or omission or alleged omission based upon information
furnished in writing to the Company by such Holder or underwriter expressly
for use in such registration statement or post-effective amendment, which
indemnification shall include such person, if any, who controls any such
Holder or underwriter within the meaning of the Securities Act of 1933;
provided, however, that the Company shall not be obligated to so indemnify any
such Holder or underwriter unless such Holder or underwriter shall at the same
time reciprocally indemnify the Company, its directors, each officer signing
the related registration statement or post-effective amendment and each person,
if any, who controls the Company within the meaning of the Securities Act of
1933 from and against any and all losses, claims, damages and liabilities,
joint and several, to which the Company or any such person may become subject
under the Securities Act of 1933, or otherwise, caused by, arising out of or
based upon any true statement or alleged untrue statement of a material fact
contained in such registration statement or post-effective amendment or any
prospectus included therein, or caused by, arising out of or based upon the
omission or alleged omission to state therein a material fact required to be
stated therein or necessary to make the statements therein not misleading, and
to reimburse the Company and each such person for any legal or other expenses
reasonably incurred in connection with investigating or defending any such
loss, claim, damage, liability or action, but only to the extent that such
untrue statement or alleged untrue statement, omission or alleged omission is
caused by, arises out of or is based upon information furnished in writing to
the Company by such Holder or underwriter expressly for use in such
registration statement or post-effective amendment.

        Section 6.      Company Covenants.
                        ------------------

                6.1.    Reservation and Issuance of Warrant Shares.  The
Company hereby undertakes until expiration of this Warrant to reserve for
issuance and/or delivery upon exercise of this Warrant, such number of shares
of its Common Stock as shall be required for issuance and/or delivery upon
exercise hereon in full and agrees that all Warrant Shares so issued and/or
delivered will be validly issued, fully paid, and non-assessable and further
agrees to pay all taxes and charges that may be imposed upon such issuance
and/or delivery.
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                6.2.    Officer's Certificate.  In the event the Exercise Price
shall be adjusted as required by Section 2 hereof, the Company shall mail to
the Holder an officer's certificate setting forth the adjustments so required
and including, in reasonable detail, the method of calculating the adjustments
and the transaction requiring the adjustment.

        Section 7.      Miscellaneous.
                        --------------

                7.1.    Status of Holder.  The Holder shall not be entitled to
vote or receive dividends and shall not otherwise be deemed a shareholder of
the Company.

                7.2.    Notices.  All notices required hereunder shall be sent
by first-class mail, postage prepaid, and shall be addressed, if to the Holder,
to the last known address furnished to the Company and if to the Company, to:
Cistron Biotechnology, Inc., 10 Bloomfield Avenue, Pine Brook, New Jersey
07058, Attn: Bruce Galton, Chairman and Chief Executive Officer, unless
another address is designated in writing by the Holder of the Company.

                7.3.    Binding Effect.  This Warrant shall be binding upon
the Company, its successors, and/or assigns and upon the Holder.

                7.4.    Governing Law.  The validity, interpretation and
performance of this Warrant shall be governed by the laws of the State of
New York.

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		IN WITNESS WHEREOF, this Warrant has been duly executed by
the Company under its corporate seal as of the 30th day of October 1998. 



                                            CISTRON BIOTECHNOLOGY, INC.  


                                            By:/s/BRUCE C. GALTON
                                               ------------------
                                            Name: BRUCE C. GALTON
                                            Title: Chairman of the Board and
                                                   Chief Executive Officer


ATTEST:


/s/SEITH I. TRUWIT, ESQ.
------------------------
Name: SETH IT TRUWIT, ESQ.

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FORM OF ASSIGNMENT

                 (To be signed only upon such assignment)



		FOR VALUE RECEIVED, the undersigned hereby sells, assigns
and transfers unto 
the right represented by the within Warrant to purchase, from CISTRON 
BIOTECHNOLOGY, INC. (the "Company"), shares of the Common Stock of the
Company, to which the within Warrant relates, and appoints

attorney to transfer said right, with full power of substitution in the 
premises.

Dated:

                                          ______________________________
                                          (Signature must conform in all
                                           respects to name of holder as
                                           specified on the face of the 
                                           Warrant)                    


ATTEST:


_____________________________
Name:

                                 -10-
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FORM OF SUBSCRIPTION

                (To be signed only upon exercise of Warrant)



To:	CISTRON BIOTECHNOLOGY, INC.



		The undersigned, the holder of the within Warrant, hereby
irrevocably elects to exercise the purchase rights represented by said
Warrant for, and to purchase thereunder, shares of Common Stock of the
Company, and herewith makes payment of $        therefor, consents to the
affixation of a legend on the certificate for such shares to the effect
that such shares have not been registered under the Securities Act of 1933,
as amended (the "Act"), and may be transferred only in compliance with the
Act, and requests that such certificate(s) be issued in the name of and be
delivered to

whose address is
and if such shares shall not be all of the shares purchased hereunder, that
a new Warrant of like tenor for the balance of shares purchasable hereunder
be delivered to the undersigned.


Dated:                                    _________________________________
                                          (Signature must conform in all
                                           respects to name of holder as
                                           specified on the face of the
                                           Warrant)