1
                                                                     Exhibit 4-J



                                   EXHIBIT A

                         REGISTRATION RIGHTS AGREEMENT


     THIS REGISTRATION RIGHTS AGREEMENT is made as of the _ day of May, 1996,
by and between UNIMED PHARMACEUTICALS, INC, a Delaware corporation (the
"Company") and BIOCHEM PHARMA (INTERNATIONAL) [NC., a corporation organized
under the laws of Canada (the "Holder").

                                    RECITALS

     WHEREAS, the Company and the Holder have entered into an agreement
providing for the purchase by the Holder of shares of common stock of the
Company; and

     WHEREAS, the Holder wishes to have the right to require the Company to
register the shares of common stock which it has agreed to purchase; and

     WHEREAS, the Company is willing to grant those rights, subject to certain
terms and conditions;

     NOW, THEREFORE, THE PARTIES HEREBY AGREE AS FOLLOWS:

     1. DEFINITIONS. For purposes of this Agreement:

           (a) The term "Stock Purchase Agreement" means that certain Stock
      Purchase Agreement, dated as of May 9, 1996, between the Company and the
      Holder.

           (b) The term "Securities Act" means the Securities Act of 1933, as
      amended.

           (c) The term "Blue Sky laws" means the applicable state securities
      laws and regulations.

           (d) The term "register," "registered," and "registration" refer to a
      registration effected by preparing and filing a registration statement or
      similar document in compliance with the Securities Act.

           (e) The term "Registrable Securities" means any and all shares of
      Common Stock purchased by the Holder pursuant to the Stock Purchase
      Agreement, and any additional shares of Common Stock issued to the Holder
      as a dividend or other distribution with respect to, or in exchange for
      or in replacement of, such Common





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      Stock, excluding in all cases, however, any Registrable Securities sold
      by a person in a transaction in which his rights under Section 2 are not
      assigned.

           (f) The term "SEC" means the Securities and Exchange Commission.

           (g) The number of shares of "Registrable Securities then
      outstanding" shall be determined by the number of shares of Common Stock
      outstanding which are Registrable Securities as of the time such
      determination is made.

     2. REGISTRATION RIGHTS. The Company covenants and agrees as follows:

           2.1 REQUEST FOR REGISTRATION.

                 (a) If the Company shall receive at any time after the second
            anniversary of the date hereof and (i) within sixty (60) days of
            the end of any of its first three fiscal quarters of each fiscal
            year or (ii) within one hundred twenty (120) days of the end of any
            fiscal year, a written request from the Holder that the Company
            file a registration statement under the Securities Act covering the
            registration of at least fifty percent (50%) of the Registrable
            Securities then outstanding and which represents an amount of
            Registrable Securities that would result in a sale by the Holder of
            the lesser of all Registrable Securities received by the Holder
            under the Stock Purchase Agreement for an aggregate offering price
            in excess of $200,000, then the Company shall, subject to the
            limitations of subsection 2.1(d), effect as soon as practicable.
            and in any event shall use its best efforts to file with the SEC
            within forty-five (45) days after the end of the fiscal quarter or
            fiscal year, as the case may be, in which such request was made,
            the registration under the Securities Act of all Registrable
            Securities which the Holder requests to be registered, and after
            such filing use its best efforts to cause such registration to be
            declared effective as soon as practicable; provided, however, that
            the rights of the Holder under this Section 2 shall be temporarily
            suspended during any period following a notice from the Company to
            such Holder under Section 2.2 with respect to a firm commitment
            underwriting, until such proposed registration shall have become
            effective, or shall be abandoned.

           (b) If the Holder intends to distribute the Registrable Securities
      covered by its request by means of an underwriting, it shall so advise
      the Company as a part of its request made pursuant to this Section 2.1.
      The underwriter will be selected by the Holder and shall be acceptable to
      the Company, but the Company shall not unreasonably withhold such
      acceptance. The Holder shall (together with the Company as provided in
      subsection 2.3(e)) enter into an underwriting agreement in customary form
      with the underwriter or underwriters selected for such underwriting by
      the Holder.





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           (c) The Company is obligated to effect only one (1) such
      registration pursuant to this Section 2.1 (counting for these purposes
      only a registration which has been declared effective and pursuant to
      which all Registrable Securities included in such registration have been
      sold).

           (d) Notwithstanding the foregoing, if the Company shall furnish to
      the Holder a certificate signed by an appropriate officer of the Company
      stating that in the good faith judgment of the Board of Directors of the
      Company, it would be detrimental to the Company and its stockholders for
      such registration statement to be filed and it is therefore appropriate
      to defer the filing of such registration statement, the Company shall
      have the right to defer such filing for a period of not more than 60 days
      after receipt of the request of the Holder, and during such 60 day
      period, the Holder shall not request any additional registration;
      provided, however, that the Company may not utilize this right more than
      once in any twelve month period.

      2.2 THE COMPANY REGISTRATION. If (but without any obligation to do so) at
any time after the second anniversary of the date hereof the Company proposes
to register (including for this purpose a registration effected by the Company
for stockholders other than the Holder) any of its stock or other securities
under the Securities Act in connection with the public offering by the Company
of such securities solely for cash (other than a registration relating solely
to the sale of securities to participants in a stock plan of the Company, or a
registration on any form which does not include substantially the same
information as would be required to be included in a registration statement
covering the sale of the Registrable Securities), the Company shall, at such
time, promptly give the Holder written notice of such registration. Upon the
written request of the Holder given within twenty (20) days after mailing of
such notice by the Company, the Company shall, subject to the provisions of
Sections 2.7 and 3.1 and the rights of such other stockholders, cause to be
registered under the Securities Act all of the Registrable Securities that such
Holder has requested to be registered.

      2.3 OBLIGATIONS OF THE COMPANY. Whenever required under this Section 2 to
effect the registration of any Registrable Securities, the Company shall, as
expeditiously as reasonably possible:

           (a) Prepare and file with the SEC a registration statement with
      respect to such Registrable Securities and use its best efforts to cause
      such registration statement to become effective, and, upon the request of
      the Holder, keep such registration statement effective for up to one
      hundred eighty (180) days.

           (b) Prepare and file with the SEC such amendments and supplements to
      such registration statement and the prospectus used in connection with
      such registration statement as may be necessary to comply with the
      provisions of the Securities Act with respect to the disposition of all
      securities covered by such registration statement.





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           (c) Furnish to the Holder such numbers of conformed copies of such
      registration statement and each amendment and supplement thereto
      (together with all exhibits filed therewith), such numbers of copies of a
      prospectus. including a preliminary prospectus, in conformity with the
      requirements of the Securities Act, and such other documents as they may
      reasonably request in order to facilitate the disposition of Registrable
      Securities owned by it.

           (d) Use its best efforts to register and qualify the securities
      covered by such registration statement under such other securities or
      Blue Sky laws of such jurisdictions as shall be reasonably requested by
      the Holder, provided that the Company shall not be required in connection
      therewith or as a condition thereto to qualify to do business or to file
      a general consent to service of process in any such states or
      jurisdictions.

           (e) In the event of any underwritten public offering, enter into and
      perform its obligations under an underwriting agreement, in usual and
      customary form, with the managing underwriter of such offering. The
      Holder shall also enter into and perform its obligations under such an
      agreement. The Holder may require that any and all representations given
      for the benefit of the underwriters also be given to the Holder.

           (f) Notify the Holder at any time when a prospectus relating thereto
      is required to be delivered under the Securities Act of the happening of
      any event as a result of which the prospectus included in such
      registration statement, as then in effect, includes an untrue statement
      of a material fact or omits to state a material fact required to be
      stated therein or necessary to make the statements therein not misleading
      in the light of the circumstances then existing.

           (g) Furnish, at the request of the Holder, on the date that such
      Registrable Securities are delivered to the underwriters for sale in
      connection with a registration pursuant to Section 2, if such securities
      are being sold through underwriters, or, if such securities are not being
      sold through underwriters, on the date that the registration statement
      with respect to such securities becomes effective, (i) an opinion, dated
      such date, of the counsel representing the Company for the purposes of
      such registration, in form and substance the Holders or underwriters may
      reasonably request, addressed to the underwriters, if any, and to the
      Holder and (ii) a letter dated such date, from the independent public
      accountants of the Company, in form and substance as is customarily given
      by independent public accountants to underwriters in an underwritten
      public offering, addressed to the underwriters, if any, and to the
      Holder.

      2.4 FURNISH INFORMATION. It shall be a condition precedent to the
obligations of the Company to take any action pursuant to Section 2 with
respect to the Registrable Securities that the Holder shall furnish to the
Company such information regarding itself, the Registrable Securities held by
it, and the intended method of disposition of such securities as shall be
required to effect the registration of the Holder's Registrable Securities.





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     2.5 EXPENSES OF DEMAND REGISTRATION. All expenses (other than legal
fees and expenses of counsel for the Holder and underwriting discounts and
commissions) incurred in connection with registrations, filings or
qualifications pursuant to Section 2.1, including (without limitation) all
registration, filing and qualification fees, printers' and accounting fees,
fees and disbursements of counsel for the Company shall be borne by the
Company; provided, however, that the Company shall not be required to pay for
any expenses of any registration proceeding begun pursuant to Section 2.1 if
the registration request is subsequently withdrawn at the request of the
Holder, unless the Holder agrees to forfeit its right to such demand
registration pursuant to Section 2.1; provided further, however, that if at the
time of such withdrawal, the Holder has learned of a material adverse change in
the condition, business, or prospects of the Company from that known to the
Holder at the time of its request and has withdrawn the request with reasonable
promptness following disclosure by the Company of such material adverse change,
then the Holder shall not be required to pay any of such expenses and shall
retain its rights pursuant to Section 2.1.

      2.6 EXPENSES OF THE COMPANY REGISTRATION. The Company shall bear and pay 
all expenses incurred in connection with any registration, filing or
qualification of Registrable Securities with respect to the registrations
pursuant to Section 2.2 for the Holder, including (without limitation) all
registration, filing,   and qualification fees, printers and accounting fees
relating or apportionable thereto, but excluding legal fees and expenses of
counsel for the Holder, underwriting discounts and commissions relating to
Registrable Securities, and those fees, if any, which are required by applicable
Blue Sky laws or regulations to be borne by Holder as a condition to
qualification.

      2. 7 UNDERWRITING REQUIREMENTS. In connection with any offering involving 
an underwriting of shares of the Company's capital stock, the Company shall not
be required under Section 2.2 to include any of the Holder's securities in such 
underwriting unless it accepts the terms of the underwriting as agreed upon
between the Company and the underwriters selected by it (or by other persons
entitled to select the underwriters), and then only in such quantity as the
underwriters determine in their sole discretion will not, jeopardize the success
of the offering by the Company. If the total amount of securities, including
Registrable Securities, requested by stockholders to be included in such
offering exceeds the amount of securities to be sold, other than by the Company,
the underwriters determine in their sole discretion is compatible with the
success of the offering, then the Company shall be required to include in the
offering only that number of such securities, including Registrable Securities,
which the underwriters determine in their sole discretion will not jeopardize
the success of the offering of the securities so included to be apportioned,
subject to the prior rights, if any, of the stockholders other than the Holder,
pro rata among the selling stockholders according to the total amount of
securities entitled to be included therein owned by each selling stockholder or
in such other proportions as shall mutually be agreed to by such selling
stockholders. For purposes of the preceding parenthetical concerning
apportionment, for any selling stockholder which is a Holder of Registrable
Securities and which is a partnership or corporation, the partners, retired
partners and





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     stockholders of such holder, or the estates and family members of any such
partners and retired partners and any trusts for the benefit of any of the
foregoing persons shall be deemed to be a single "selling stockholder", and any
pro-rata reduction with respect to such "selling stockholder" shall be based
upon the aggregate amount of shares carrying registration rights owned by all
entities and individuals included in such "selling stockholder", as defined in
this sentence.

      2.8 DELAY OF REGISTRATION. No Holder shall have any right to obtain or 
seek an injunction restraining or otherwise delaying any such registration as   
the result of any controversy that might arise with respect to the
interpretation or implementation of Section 2.

      2.9 INDEMNIFICATION. In the event any Registrable Securities are included
in a registration statement under Section 2:

           (a) To the extent permitted by law, the Company will indemnify and
      hold harmless the Holder, any underwriter (as defined in the Securities
      Act) for such Holder and each person, if any, who controls such Holder or
      underwriter within the meaning of the Securities Act or the Securities
      Exchange Act of 1934, as amended (the "1934 Act"), against any losses,
      claims, damages, or liabilities (joint or several) to which they may
      become subject under the Securities Act, the 1934 Act or other federal or
      state law, insofar as such losses, claims, damages, or liabilities for
      actions in respect thereof) arise out of or are based upon any of the
      following statements, omissions or violations (collectively a
      "Violation"): (i) any untrue statement or alleged untrue statement of a
      material fact contained in such registration statement, including any
      preliminary prospectus or final prospectus contained therein or any
      amendments or supplements thereto, (ii) 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, or (iii) any
      violation or alleged violation by the Company of the Securities Act, the
      1934 Act, any state securities law or any rule or regulation promulgated
      under the Securities Act, the 1934 Act or any state securities law, and
      the Company will pay to the Holder, underwriter or controlling person, as
      incurred, any legal or other expenses reasonably incurred by them in
      connection with investigating or defending any such loss, claim, damage,
      liability, or action; provided, however, that the indemnity agreement
      contained in this subsection 2.9(a) shall not apply to amounts paid in
      settlement of any such loss, claim, damage. liability, or action if such
      settlement is effected without the consent of the Company, which consent
      shall not be unreasonably withheld, nor shall the Company be liable he
      any such case for any such loss, claim, damage, liability, or action to
      the extent that it arises out of or is based upon a Violation which
      occurs in reliance upon and in conformity with written information
      furnished expressly for use in connection with such registration by any
      such Holder, underwriter or controlling person, or in a situation in
      which the Violation was caused by the intentional act or omission of such
      Holder acting either in his individual capacity, or in the capacity as an
      officer of the Company.





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           (b) To the extent permitted by law, the Holder will indemnify and
      hold harmless the Company, each of its directors, each of its officers
      who has signed the registration statement, each person, if any, who
      controls the Company within the meaning of the Securities Act, any
      underwriter, any other person selling securities in such registration
      statement and any controlling person of any such underwriter or other
      person, against any losses, claims, damages, or liabilities (joint or
      several) to which any of the foregoing persons may become subject, under
      the Securities Act, the 1934 Act or other Federal or state law insofar as
      such losses, claims, damages, or liabilities for actions in respect
      thereto) arise out of or are based upon any Violation, in each case to
      the extent (and only to the extent) that such Violation occurs in
      reliance upon and in conformity with written information furnished by
      such Holder expressly for use in connection with such registration; and
      the Holder will pay, as incurred, any legal or other expenses reasonably
      incurred by any person intended to be indemnified pursuant to this
      subsection 2.9(b), in connection with investigating or defending any such
      loss, claim, damage, liability, or action; provided, however, that the
      indemnity agreement contained in this subsection 2.9(b) shall not apply
      to amounts paid in settlement of any such loss, claim, damage, liability
      or action if such settlement is effected without the consent of the
      Holder, which consent shall not be unreasonably withheld, nor shall the
      Holder be liable in any such case for any such loss, claim, damage,
      liability, or action to the extent that it arises out of or is based upon
      a Violation which occurs in reliance by the Holder upon and in conformity
      with written information, if any, furnished by the Company or any
      underwriter or person controlling the Company expressly to the Holder for
      use in connection with such registration.

           (c) Promptly after receipt by an indemnified party under this
      Section 2.9 of notice of the commencement of any action (including any
      governmental action), such indemnified party will, if a claim in respect
      thereof is to be made against any indemnifying party under this Section
      2.9, deliver to the indemnifying party a written notice of the
      commencement thereof and the indemnifying party shall have the right to
      participate in ( at participant's own expense), and, to the extent the
      indemnifying party so desires, jointly with any other indemnifying party
      similarly noticed, to assume the defense thereof with counsel mutually
      satisfactory to the parties; provided, however, that an indemnified party
      (together with all other indemnified parties which may be represented
      without conflict by one counsel) shall have the right to retain one
      separate counsel, with the fees and expenses to be paid by the
      indemnifying party, if representation of such indemnified party by the
      counsel retained by the indemnifying party would be inappropriate due to
      actual or potential differing interests between such indemnified party
      and any other party represented by such counsel in such proceeding. The
      failure to deliver written notice to the indemnifying party within a
      reasonable time of the commencement of any such action shall not relieve
      an indemnifying party of liability for indemnification hereunder, except
      to the extent that the indemnifying party is actually prejudiced by such
      failure, but in any event the omission so to deliver written





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           notice to the indemnifying party will not relieve it of any
      liability that it may have to any indemnified party otherwise than under
      this Section 2.9.

           (d) If the indemnification provided for in this Section 2.9 is held
      by a court of competent jurisdiction to be unavailable to an indemnified
      party with respect to any loss, liability, claim, damage, or expense
      referred to therein, then the indemnifying party, in lieu of indemnifying
      such indemnified party hereunder, shall contribute to the amount paid or
      payable by such indemnified party as a result of such loss, liability,
      claim, damage, or expense in such proportion as is appropriate to reflect
      the relative fault of the indemnifying party on the one hand and of the
      indemnified party on the other in connection with the statements or
      omissions that resulted in such loss. liability, claim, damage, or
      expense as well as any other relevant equitable considerations. The
      relative fault of the indemnifying party and of the indemnified party
      shall be determined by reference to, among other things. whether the
      untrue or alleged untrue statement of a material fact or the omission to
      state a material fact relates to information supplied by the indemnifying
      party or by the indemnified party and the parties' relative intent,
      knowledge, access to information, and opportunity to correct or prevent
      such statement or omission.

           (e) Notwithstanding the foregoing, to the extent that the provisions
      on indemnification and contribution contained in the underwriting
      agreement entered into in connection with the underwritten public
      offering are in conflict with the foregoing provisions, the provisions in
      the underwriting agreement shall control.

           (f) No person shall be entitled to indemnification or contribution
      hereunder if such person shall have been finally determined to have been
      guilty of fraudulent misrepresentation under Section I l(f) of the
      Securities Act.

           (g) The obligations of the Company and Holder under this Section 2.9
      shall survive the completion of any offering of Registrable Securities in
      a registration statement under Section 2, and otherwise.

      2.10 REPORTS UNDER SECURITIES EXCHANGE ACT OF 1934. With a view to making
available to the Holder the benefits of Rule 144 promulgated under the
Securities Act and any other rule or regulation of the SEC that may at any time
permit the Holder to sell securities of the Company to the public without
registration, the Company agrees to:

           (a) make and keep public information available, as those terms are
      understood and defined in SEC Rule 144, at all times;

           (b) file with the SEC in a timely manner all reports and other
      documents required of the Company under the Securities Act and the 1934
      Act; and





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           (c) furnish to any Holder, so long as the Holder owns any
      Registrable Securities, forthwith upon request (i) a written statement by
      the Company that it has complied with the reporting requirements of SEC
      Rule 144, the Securities Act and the 1934 Act, (ii) a copy of the most
      recent annual or quarterly report of the Company and such other reports
      and documents so filed by the Company, and (iii) such other information
      as may be reasonably requested in availing the Holder of any rule or
      regulation of the SEC which permits the selling of any such securities
      without registration or pursuant to such form, but only if such
      information is necessary in order to determine whether the exemption is
      available, or in order to utilize the exemption.

     2.11 "MARKET STAND-OFF" AGREEMENT. The Holder hereby agrees that,
during the period of duration, not to exceed ninety (90) days, specified by the
Company and an underwriter of Common Stock or other securities of the
Company, following the effective date of a registration statement of the
Company filed under the Securities Act, it shall not, to the extent requested
by the Company and such underwriter, directly or indirectly sell, offer to
sell, contract to sell (including, without limitation, any short sale), grant
any option to purchase or otherwise transfer or dispose of (other than to
donees who agree to be similarly bound) any securities of the Company held by
it at any time during such period except Common Stock included in such
registration; provided, however, that the period of duration specified above
may be shortened with the prior written consent of the underwriter and the
Company. In order to enforce the foregoing covenant, the Company may impose
stop-transfer instructions with respect to the Registrable Securities of the
Holder (and the shares or securities of every other person subject to the
foregoing restriction) until the end of such period.

      2.12 WITHDRAWAL RIGHTS REALLOCATION. If the Holder disapproves of the 
terms of any such underwriting, it may elect to withdraw therefrom by written
notice  to the Company and the underwriters.

      3. MISCELLANEOUS.

      3.1 LIMITATION OF REGISTRATION RIGHTS. Any provision herein to the 
contrary notwithstanding, the Holder shall not have any registration rights
hereunder (including rights under Sections 2.1 and 2.2), and all rights to
registration    hereunder shall terminate and shall be of no further force or
effect if (a) the Holder is permitted to sell all of its Registrable Securities
at the same time without restriction under Rule 144 and (b) the average weekly
trading volume of shares of the same class as the Registrable Securities during
the three (3) month period immediately prior to the date on which the Holder
wishes to exercise its registration rights is equal to or greater than the
number of Registerable Securities owned by such Holder.

      3.2 COORDINATION WITH OTHER RIGHTS. This Agreement, and the rights of the
Holder, are subject to the rights of other holders of securities of the Company
in effect on the date hereof, which are described on a Schedule to the Stock
Purchase Agreement. Without limitation





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     of the foregoing, the rights of the Holder to a demand registration and to
be included in other registrations may be superseded by the rights and actions
of such other holders to have their securities registered and to be included in
registration statements filed by the Company at its own initiative or pursuant
to demand registration rights of others. By execution hereof, the Holder
consents and agrees to all of such prior rights. Notwithstanding the foregoing,
in no event shall the prior rights of any person have the effect of depriving
the Holder of its one demand registration right, and if as a result of the
exercise of any such prior rights, the Holder is unable to include in its
demand registration all of the Registrable Securities which it wants to
include, its demand registration rights shall continue, notwithstanding the
exercise of such one demand, until the earlier of the time when all of the
Registrable Securities requested to be included in such demand registration
shall have been sold in transactions under which the purchasers are not further
restricted from sales of such securities, or registration rights are otherwise
terminated under the provisions of this Agreement.

      3.3 SUCCESSORS AND ASSIGNS.  Except as otherwise provided herein, the 
terms and conditions of this Agreement shall inure to the benefit of and be
binding upon the respective successors and assigns of the parties (including
transferees of any shares of Registrable Securities). Nothing in this Agreement,
express or implied, is intended to confer upon any party other than the parties
hereto or their respective successors and assigns any rights, remedies,
obligations, or liabilities under or by reason of this Agreement, except as
expressly provided in this Agreement. Any provision herein to the contrary
notwithstanding, it the Holder shall transfer any of the Registrable Securities,
then the rights hereunder may also be transferred with such Registrable
Securities, but in such event, the Holder and such assignees shall have no
greater rights, as a group, than the Holder had under this Agreement prior to
such transfer, and the Holder and each such assignee shall appoint one person
who shall act hereunder on behalf of the Holder and all of the assignees.

      3.4 GOVERNING LAW. This Agreement shall be governed by, and construed in
accordance with, the laws of the State of Delaware, without giving effect to
its conflicts of laws principles.

      3.5 TITLES AND SUBTITLES. The titles and subtitles used in this Agreement
are used for convenience only and are not to be considered in construing or
interpreting this Agreement.

      3.6 NOTICES. Any notice, request, delivery, approval or consent required
or permitted to be given under this Agreement shall be in writing and shall be  
deemed to have been sufficiently given if delivered personally, transmitted by
telecopier (confirmation of receipt by confirmed facsimile transmission being
deemed receipt of communication sent by telecopy) or five days after it was
sent, by registered letter (or its equivalent) to the party to which it is
directed at its address shown below or such other address as such party shall
have last given by notice delivered in accordance herewith to the other party:





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     (a) If to the Investor, addressed to:

            BIOCHEM PHARMA (INTERNATIONAL) INC.
            275 Armand-Frappier Boulevard
            Laval, Quebec, Canada
            H7V 4A7
            Attention: Mr. Michael Grey
            Telecopier: (514) 978-7767

         With a copy to:

            BIOCHEM PHARMA INC.
            at the same address
            Attention: Mr. Charles Tessier, VP, Legal Affairs and 
              Corporate Secretary
            Telecopier: (514) 978-7755;

     (b) If to the Company, addressed to:

             UNIMED PHARMACEUTICALS, INC.
             2150 East Lake Cook Road
             Buffalo Grove, Illinois USA 60089-1862
             Attention: Stephen M. Simes, President & CEO
             Telecopier: (847) 541 -2533

     with a copy to:

             Stephen E. Goodman
             Schwartz & Freeman
             401 N. Michigan Ave.
             Suite 1900
             Chicago IL USA 60611
             Telecopier: (312) 222-0818

      3.7 SEVERABILITY. If one or more provisions of this Agreement are held 
to be unenforceable under applicable law, such provision shall be excluded from
this Agreement and the balance of the Agreement shall be interpreted as if
such provision were so excluded and shall be enforceable in accordance with its
terms.

      3.8 SUBJECT TO STOCK PURCHASE AGREEMENT. This Agreement is subject to the
terms and conditions of the Stock Purchase Agreement. In the event of any
inconsistency between this Agreement and the Stock Purchase Agreement, the
terms of Stock Purchase Agreement shall govern. Capitalized terms used herein
which are not defined herein shall have the definitions ascribed to them in the
Stock Purchase Agreement.





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      3.9 SUBMISSION TO JURISDICTION.  The Company and the Holder hereby
irrevocably submit to the jurisdiction and exclusive venue of any state or
Federal court located in the State of Delaware over any action or proceeding,
to enforce or defend any right under this Agreement or the Stock Purchase
Agreement, or under any amendment, instrument, document, or agreement
delivered, or that may in the future be delivered, in connection herewith or
therewith, and the Company and the Holder hereby irrevocably agree that all
claims to respect of any such action or proceeding may be heard and determined
in such state or Federal court.  The Company and the Holder hereby irrevocably
waive, to the fullest extent they may effectively do so, the defense of an
inconvenient forum to the maintenance of any such action or proceeding.  The
Company and the Holder agree that a final judgment in any such action or
proceeding shall be conclusive and may be enforced in other jurisdictions by
suit on the judgment or in any other manner provided by law.  The Company and
the Holder agree not to institute any legal action or proceeding against the
Company, the Holder or any of their directors, officers, employees, agents or
properties, arising out of or relating to this agreement or any of the
documents referred to above, in any court other than one hereinabove specified
in this Section 3.9.  Nothing in this Section 3.9 shall affect the right of the
Company or the Holder to serve legal process in any other manner permitted by
law, or the right of the Company or the Holder to bring any action or
proceeding against the Property of the Company or the Holder in the courts of
any other jurisdictions.





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   13





     IN WITNESS WHEREOF, the parties have executed this Registration Rights
Amendment as of the date first above written.


                                           THE COMPANY:
 
                                           UNIMED PHARMACEUTICALS, INC.,


                                           By:
                                           Name and Title:

                                           HOLDER:

                                           BIOCHEM PHARMA (INTERNATIONAL) INC.

 
                                           By:
                                           Name and Title:


                                           By:
                                           Name and Title:





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