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                                                                   EXHIBIT 10.47



May 23, 2001

Mr. Robert C. Salisbury
3252 Walter Travis Drive
Sarasota, FL 34240

Dear Mr. Salisbury:

This letter is to confirm our mutual understanding with respect to the terms and
conditions under which you agree to provide Viragen Inc. ("Viragen"), directly
or through its subsidiaries, affiliated and associated companies, with services
in a consulting capacity during the period beginning June 1, 2001 and ending May
31, 2004 (hereinafter referred to as the "CONSULTING PERIOD"), it being
understood that this CONSULTING PERIOD may be extended by mutual agreement in
writing.

5.       "Consulting capacity" herein means that you will provide VIRAGEN with
         the full benefit of your knowledge, experience and skill with respect
         to strategic planning, questions, collaborations or partnering
         arrangements in pharmaceutical and/or biotech related projects. It is
         anticipated that you will initially focus your efforts on VIRAGEN's
         oncology related projects.

6.       VIRAGEN acknowledges that other clients may use your consulting
         services and it is understood and agreed that you are not to disclose
         to VIRAGEN any confidential information of other parties, including
         past and present clients. VIRAGEN will rely upon your ethical judgment
         to avoid conflicts of interest. It is understood and agreed that during
         the CONSULTING PERIOD you shall not consult for other parties regarding
         the same subject matter set forth above for the consulting capacity
         covered by this Agreement.

7.       You will make yourself available to VIRAGEN from time-to-time for
         consulting services in the consulting capacity stated herein.

8.       VIRAGEN agrees to compensate you as follows:

         a)       Reimbursement of actual expenses incurred.

         b)       Warrant grants to purchase VIRAGEN, Inc. common stock upon
                  meeting of the following milestones identified and sourced
                  through your efforts:

                  i)       10,000 shares upon the delivery of an agreed plan of
                           action from the development and collaboration of the
                           three oncology projects.

                  ii)      50,000 shares upon the signing of a definitive
                           licensing/collaboration agreement with a
                           pharmaceutical or biotech partner.

                  iii)     25,000 shares upon the Viragen's receipt of the first
                           $1 million in aggregate milestone, licensing fees
                           and/or equity investments from the pharmaceutical or
                           biotech partner.

                  iv)      25,000 shares upon the Viragen's receipt of the
                           second $1 million in aggregate milestone, licensing
                           fees and/or equity investments from the
                           pharmaceutical or biotech partner.


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Robert C. Salisbury
Consulting Agreement
May 23, 2001
Page 2 of 3 Pages



         c)       The warrants shall have an exercise price equal to 115% of the
                  fair market value of the Viragen stock upon the date of the
                  grant and would expire five years from the date of the grant.
                  The warrants will be exercisable 50% one year after the date
                  of grant, 50% two years after the date of the grant.

5.       During the discussions leading up to this Agreement and during the
         CONSULTING PERIOD and any extensions thereof you have acquired and will
         acquire from VIRAGEN information which VIRAGEN considers to be
         proprietary and confidential, for example, information with respect to
         materials, compounds, formulations, samples, processes, methods,
         apparatus, operations and present and future plans of VIRAGEN. You
         agree to keep confidential and not to use, except in connection with
         services in a consulting capacity provided VIRAGEN, all such
         information, as well as all information developed by you as a result of
         your services to VIRAGEN under this Agreement, and not to divulge any
         such information to others at any time. Upon termination of this
         Agreement or at any other time VIRAGEN requests, you will transmit to
         VIRAGEN any written, printed or other materials embodying such
         information, including all copies, excerpts thereof, and samples given
         to you or prepared by you in connection with your work for VIRAGEN
         under this Agreement. These obligations on your part with respect to
         VIRAGEN information shall continue at all times beyond the CONSULTING
         PERIOD and any extensions thereof.

         Notwithstanding the above, this Agreement shall not restrict your use
         or disclosure of information which:

         a)       is or later becomes publicly known through no fault of yours;

         b)       was already known to you other than as a result of any
                  existing fiduciary capacity with VIRAGEN as evidenced by your
                  written records at the time of its receipt from VIRAGEN; or

         c)       is lawfully and in good faith made available to you without
                  restriction on disclosure or use by a third party.

         Specific information disclosed to you by VIRAGEN shall not be deemed to
         be available to the public or in your prior possession merely because
         it is embraced by more general information available to the public or
         in your prior possession.

6.       Any and all information, inventions and discoveries, whether or not
         patentable, which you develop, conceive and/or make:

         a)       within the CONSULTING PERIOD and any extensions mutually
                  agreed upon and which are related to any questions or problems
                  with respect to which VIRAGEN has utilized your services under
                  this Agreement, and/or

         b)       as a result of confidential information received from VIRAGEN,
                  shall be the sole and exclusive property of VIRAGEN. You will,
                  upon request of VIRAGEN, promptly execute any and all
                  applications, assignments or other instruments which VIRAGEN
                  shall deem necessary or useful in order to apply for and
                  obtain patent protection worldwide for said inventions and
                  discoveries, and in order to assign and convey to VIRAGEN the
                  sole and exclusive right, title and interest in and to said
                  inventions and discoveries and patent applications and patents
                  thereon. VIRAGEN will bear the costs of preparation and filing
                  of all said patent applications.


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Robert C. Salisbury
Consulting Agreement
May 23, 2001
Page 3 of 3 Pages



7.       While providing services for VIRAGEN in a consulting capacity you will
         be acting as an independent contractor and not as an employee or agent
         of VIRAGEN and you will not be entitled to any of the benefits, direct
         or indirect, of an employee of VIRAGEN.

8.       The validity, interpretation and performance of this Agreement and any
         dispute connected herewith shall be governed and construed in
         accordance with the laws of the State of Florida, USA.

9.       The parties agree that all works created pursuant to this Agreement are
         deemed to be assigned to VIRAGEN, including all copyrights throughout
         the world. You agree to execute any documents deemed necessary by
         VIRAGEN to record said assignments. You shall also secure for VIRAGEN
         the assignment of copyrights in any work created by others pursuant to
         this Agreement, and shall notify VIRAGEN prior to commencing any
         activity toward creation if the copyright of any such work cannot be
         secured. The parties agree that all works made for hire under this
         Agreement shall vest in VIRAGEN.

10.      VIRAGEN will not be liable for any loss, injury or damage incurred by
         you or by a third party as a result of your performance of the
         services, including any loss, injury or damage resulting from the
         negligent or willful act or omission by you. You shall indemnify and
         hold VIRAGEN harmless from any liability, loss, cost, and expense
         (including attorneys' fees and costs) incurred by VIRAGEN as a result
         of your breach of this agreement, negligence or willful misconduct.
         This obligation shall survive the expiration or earlier termination of
         this agreement.

If the foregoing terms and conditions meet with your understanding and approval,
please show your acceptance and agreement by signing this letter in duplicate at
the place indicated below.

Very truly yours,

VIRAGEN, INC.




By: /s/ Gerald Smith                     By: /s/ Robert C. Salisbury
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    Gerald Smith                             Robert C. Salisbury
    Chairman & CEO                           Title:
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