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                         ADDENDUM TO LEASE BETWEEN
                     VIRAGEN, INC.  AND MEDICORE, INC.
                         DATED DECEMBER 8, 1992

     WHEREAS, Viragen, Inc., a Delaware corporation ("Lessor") is the
owner of property located at 2343 West 76th Street, Hialeah, Florida and
has entered into a Lease dated December 8, 1992 ("Lease") with Medicore,
Inc. ("Lessee"); and

     WHEREAS, the parties to the Lease are mutually desirous of adding the
following terms and provisions to the Lease as hereinafter set forth.

     NOW, THEREFORE, in consideration of the sum of ten ($10) dollars and
other good and valuable consideration paid by each party to the other, the
receipt and sufficiency hereby acknowledged by both parties, and further
consideration of the extension of funds by Lessee to the Lessor as other-
wise acknowledged by the parties and as provided for herein, Lessor and
Lessee do hereby covenant and agree as follows:

     1.   All of the recital clauses hereinabove set forth are hereby
          incorporated by reference as though set forth and at length
          herein.

     2.   Lessor agrees to pay to Lessee, either through insurance reim-
          bursement Lessor receives for damages to its Premises as a
          result of the recent hurricane ("Storm Damage") and/or to the
          extent certain repairs and leasehold improvements are not
          subject to the insurance reimbursement, then through rental
          adjustments and reductions as otherwise provided for herein,
          such sums necessary for (i) maintenance and repair of the
          Premises ("Maintenance") due to the Storm Damage (such Main-
          tenance being a requirement of Section 7.1 of the Lease
          incumbent upon the Lessor), and (ii) leasehold improvements
          necessary to accommodate Lessor in order for Lessor to lease
          the Premises ("Leasehold Improvements"), both (i) Maintenance
          and (ii) Leasehold Improvements being the contingency and basis
          for Lessor having entered into the Lease.

          Lessor has been dependent upon Lessee for funds to operate since
          Lessor's inception in 1980, and Lessor is and was, at the date
          of the execution of the Lease, indebted to Lessor for advances
          up to approximately $450,000 of which $350,000 is evidenced by a
          promissory note and secured by mortgage on the Premises held by
          Lessee.

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          As of the date of this Addendum, the Maintenance expenses
          (exclusive of roof repair) and the expenses for Leasehold
          Improvements amounted to $39,542.  These sums were advanced by
          Lessee to Lessor with the understanding and agreement of the
          Lessor and Lessee that said sums were to be repaid by Lessor to
          Lessee as provided for in this Addendum.  Of said aggregate sum,
          Lessor has repaid to Lessee from its insurance proceeds for the
          Storm Damage $15,000 resulting in a balance due from Lessor to
          Lessee under the terms of this Addendum for Maintenance and
          Leasehold Improvements of $24,542 ("Aggregate Sum").  To the
          extent that Lessor is unable to make a cash reimbursement from
          its insurance proceeds for the Maintenance or otherwise make
          repayments for the Leasehold Improvements, then the Aggregate
          Sum shall be reduced in full, without interest, through and by
          deductions from rental payments due by Lessee under the Lease,
          commencing from the date hereof through the term of the Lease
          in successive continuous monthly deductions until the Aggregate
          Sum is fully paid and satisfied, subject to Section 3, below.

     3.   Lessor and Lessee understand and agree that there remain
          additional Maintenance and Leasehold Improvements to be accom-
          plished, including but not limited to replacing the lawn,
          painting, wallpaper, etc., which when properly documented and
          such funds are extended by Lessee to Lessor, will be added to
          the Aggregate sum as defined under Section 2 of this Addendum and
          shall be repaid as otherwise provided in Section 2 hereof through
          cash repayment by Lessor to Lessee or rental adjustments and
          deductions due under the Lease as otherwise set forth in Section
          2 hereinabove.

     4.   The roof repair to the extent of approximately $36,000 is not
          included in the Aggregate Sum nor in this Addendum.

     5.   The Lease otherwise remains in full force and effect.

     IN WITNESS WHEREOF, the parties have hereunto set their hands and
seals as of this 15th day of January, 1993.

ATTEST:                         VIRAGEN, INC.

/s/ Lawrence E. Jaffe           By /s/ Dennis W. Healey
---------------------------       -----------------------------
Lawrence E. Jaffe                 DENNIS W. HEALEY, President
Secretary

ATTEST:                         MEDICORE, INC.

/s/ Lawrence E. Jaffe           By /s/ Thomas K. Langbein
---------------------------       -----------------------------
Lawrence E. Jaffe                 THOMAS K. LANGBEIN, President
Secretary