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                                                                   EXHIBIT 10.13

THIS AGREEMENT is made the 15th day of February 2001

BETWEEN

VIRAGEN, INC. and its subsidiary, VIRAGEN (SCOTLAND) LIMITED ("Viragen"),
Pentlands Science Park, Bush Loan, Penicuik, Midlothian, EH26 0PZ, Scotland

AND

PENG LEE YAP, M.D., 5 Meadow Place, Edinburgh, EH9 1JZ, Scotland

WHEREAS:

Peng Lee Yap, M.D. (herein after known as "Dr. Yap" or "Consultant") is to serve
as Medical Director of Viragen and provide an advisory service and a project
service to Viragen and its affiliates upon and subject to the terms set out
below.

NOW IT IS HEREBY AGREED as follows:

1.       APPOINTMENT

         Viragen hereby appoints Dr. Yap who here by agrees to act as Medical
         Director and Consultant upon and subject to the terms set out below.

2.       CONSULTANT'S OBLIGATIONS

         2.1      Dr. Yap will provide Viragen and its subsidiaries advice on
                  matters relating to the clinical trials, research, development
                  and manufacture of OMNIFERON(TM) and other products where Dr.
                  Yap has is no pre-existing conflict of interest.

         2.2      Dr. Yap agrees to provide these services to Viragen for a
                  minimum of four (4) days each month (or more as from time to
                  time may be agreed). Dr. Yap also agrees to provide advice at
                  other times, as may be required, and to respond to such
                  requests within a reasonable time.

         2.3      Dr. Yap will provide the services to the standard of skill,
                  integrity and reliability which could reasonably be expected
                  from a consultant with skills and qualifications held by the
                  Consultant.

         INFORMATION

         Dr. Yap shall provide to Viragen upon request, written reports of his
         activities on Viragen's behalf. Dr. Yap shall also upon request be
         available for meetings with Viragen or its subsidiaries.




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3.       CONFIDENTIALITY

         3.1      Dr. Yap will operate under the Viragen Confidentiality
                  Agreement dated July 1, 1999 and attached to this document as
                  an Appendix 1.

4.       FEES AND EXPENSES

         4.1      As consideration for serving as Viragen's Medical Director and
                  the provision of the advisory services referred to in
                  paragraphs 2.1, 2.2 and 2.3 above, Viragen shall pay to Dr.
                  Yap a retainer fee of (pound)1,000 per day for a minimum of
                  four (4) days per month during the term of this Agreement
                  payable in arrears within 28 days of the date of Dr.Yap's
                  invoice for such amounts and any expenses referred to in
                  Clause 4.4 below. Time in excess of four (4) days in any one
                  calendar month will be charged at a rate of (pound)1,000 per
                  day.

         4.2      Invoices will be rendered monthly at the end of each calendar
                  month.

         4.3      Viragen will also reimburse Dr. Yap such travelling,
                  accommodation and communication costs as may be reasonably be
                  incurred in connection with the provision of the services
                  pursuant to this Agreement subject to submitting such
                  supporting evidence thereof as Viragen may reasonably require.
                  All air travel will be made by Business Class or Premium
                  Economy Class when available. All rail travel will be made by
                  First Class. Car mileage rates will be charged in accordance
                  with those recommended by the Automobile Association (of Great
                  Britain).

         4.4      For all payments from outside the United Kingdom, Viragen
                  shall pay all bank charges for remittance in Pounds Sterling
                  including any charges payable by Dr. Yap.

5        DURATION AND TERMINATION

         5.1      This Agreement shall be deemed to have commenced on 14
                  February 2001 notwithstanding the date hereof and shall
                  continue indefinitely thereafter, subject to either party's
                  right to terminate it upon one month's written notice.

         5.2      Notwithstanding the provisions of Clause 5.1 above, Viragen
                  may at any time by notice in writing, immediately terminate
                  this Agreement if Dr. Yap shall:

                  5.2.1.   be in breach of any of the terms of this Agreement
                           which, in the case of breach capable of remedy, is
                           not remedied by Dr. Yap within 21 days of receipt by
                           it of a written notice from Viragen specifying the
                           breach and requiring its remedy; or

                  5.2.2.   be incompetent, guilty of gross misconduct or any
                           negligence in respect of its obligations.





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6.       NO EMPLOYMENT OR AGENCY

         Nothing contained in this Agreement shall be construed or have effect
         as constituting any relationship of employment between Viragen and Dr.
         Yap. Dr. Yap shall not have any right or power whatsoever to contract
         on behalf of Viragen or otherwise bind Viragen in any way in relation
         to third parties unless specifically authorised to do so by Viragen.

7.       INDEMNITY OF CONSULTANT

         Viragen shall indemnify and hold harmless Consultant from and against
         any and all claims, judgements, fines, penalties, liabilities, losses,
         costs and expenses (including reasonable attorneys' fees and costs)
         asserted against or incurred by Consultant as a result of acts or
         omissions of Consultant taken or made in the course of performing his
         duties for Viragen or by reason of Consultant acting or having acted as
         a Medical Director or Consultant of Viragen, provided, however, that
         such indemnity shall not apply to acts or omissions of Consultant which
         constitute misconduct, gross negligence or which were intended by
         Consultant to personally benefit Consultant directly or indirectly, at
         the expense of Viragen, unless the matter which benefits Consultant was
         first fully disclosed to the Board of Directors of Viragen and approved
         by said Board.

8.       NOTICES

         Any notice required by this Agreement to be given by one party to the
         other shall be in writing and shall be serviced by sending the same by
         registered post or recorded delivery or leaving at the address of the
         other party specified above or at such other substitute address that
         party may notify in writing, from time to time.

9.       ENTIRE AGREEMENT

         This Agreement, including Appendix 1, sets out the active agreement and
         understanding between Dr. Peng and Viragen in relation to its subject
         matter and supersedes any previous agreement, whether written or oral,
         between the parties.

10.      GOVERNING LAW

         This Agreement shall be governed and construed in all respects with the
         Laws of Scotland.

         In witness whereof the parties have executed this Agreement the day and
         year first above written.

         Signed by         /s/ Gerald Smith
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                           Gerald Smith
                           President - Viragen, Inc.
                           Director - Viragen (Scotland) Ltd.

         For and on behalf of Viragen (Scotland) Limited


         Signed by         /s/ Peng Lee Yap
                           -----------------------------------
                           Peng Lee Yap, M.D.






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