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                                                                     EXHIBIT 4.9


(PROTHERICS LOGO)






Swedish Orphan AB
Dtottninggatan 98
S-11160 Stockholm
Sweden

14 November 2003

Dear Sirs,

Product Agreement dated January 1990 between Swedish Orphan AB (now Swedish
Orphan International AB) and Therapeutic Antibodies Inc., as amended and
restated by agreement dated 31 March 2000 between Protherics Inc. and Swedish
Orphan AB (now Swedish Orphan International AB) (the "Agreement").

We refer to the above Agreement between us in relation to the appointment of
Swedish Orphan International AB (formerly Swedish Orphan AB) as the exclusive
sales representative for the products which are set out in that Agreement. We
have agreed that the Agreement should be amended in order to extend the
territorial range of the products which are the subject of the original
agreement as follows:

1. Clause 1.0 Appointment shall be deleted and replaced with the following:

     "1.0 Appointment

      1.1 Protherics appoints Agent exclusive sales representative for:"

          (a) products specified in part 1 of Appendix A in markets listed in
              part 1 of Appendix B (the "ViperaTAb Territory"); and

          (b) products specified in part 2 of Appendix A in the markets
              specified in part 2 of Appendix B (the "DigiFeb Territory").

          This appointment is made by Protherics and is accepted by Agent upon
          and subject to the following terms and conditions.




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     1.2 For the avoidance of doubt the following terms shall bear the following
         meanings:

               "Products" shall mean the products set out in part 1 and part 2
               of Appendix A and any references to Products shall mean a
               reference to either or both of them as the case may be; and

               "Territory" means either of the ViperaTAb Territory and/or the
               DigiFab Territory.

2. Appendices A, B and C and D shall be deleted and replaced with the attached
   revised appendices A, B and C and D.

3. The amendments set out in this letter shall take effect with effect from the
   date hereof.

4. Save as amended by this letter agreement, the terms of the Agreement shall
   remain in full force and effect.

5. This letter (and any dispute, controversy, proceedings or claim of whatever
   nature arising out of, or in any way relating to, this letter or its
   formation) shall be governed by and construed in accordance with English law
   and Protherics Inc. and Swedish Orphan International AB hereby irrevocably
   submit to the exclusive jurisdiction of the courts of England and Wales to
   hear and decide any suit, action or proceedings, and/or to settle any
   disputes, which may arise out of or in connection with this letter or its
   formation.

We should be grateful if you would indicate your agreement to the amendment of
the Agreement as set out in this letter by signing and returning to us the
attached copy letter where indicated.

Yours faithfully



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for and on behalf of Protherics, Inc.

We confirm and agree to the amendment of the Agreement with effect from the date
of this letter as set out in this letter agreement.



                                                                  20/11/03
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For and on behalf of Swedish Orphan International AB           Date