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                                                                   EXHIBIT 10.64



THIS PREPAYMENT AGREEMENT is made on June 30, 1998

BETWEEN

(1)      INNOVATIVE TECHNOLOGIES GROUP PLC (No. 2867684), a company incorporated
         in England and Wales, whose registered office is at Road Three,
         Winsford Industrial Estate, Winsford, Cheshire CW7 3PD ("the Maker");
         and

(2)      POLYMEDICA CORPORATION, a Massachusetts corporation, whose principal
         place of business is at 11 State Street, Woburn, Massachusetts 01801,
         USA ("the Holder").

WHEREAS:

(A)      On 18 July 1997 the Maker issued to the Holder a promissory note ("the
         Promissory Note") for the principal amount of four million US Dollars
         (US$4,000,000) bearing interest as provided by the terms of the
         Promissory Note.

(B)      In accordance with Section VI (G) of the Promissory Note, the parties
         have agreed that the Maker shall prepay the Promissory Note, at an
         agreed discounted rate, on the terms and subject to the conditions set
         out below.

1        PREPAYMENT

         1.1      Subject to and on or about July 7, 1998, or such other day as
                  the parties shall in writing agree, being referred to as "the
                  Completion Date," the Maker shall pay to the Holder the sum of
                  one million six hundred thousand US Dollars (US$1,600,000)
                  ("the Prepayment Amount") in full and final settlement of all
                  amounts (whether of principal or interest) which are now or
                  may hereafter become payable by the Maker under the terms of
                  the Promissory Note.

                  The Holder warrants to the Maker that it is legal and
                  beneficial owner of the Promissory Note, that it has not
                  pledged, assigned, granted a security interest in or otherwise
                  encumbered the Promissory Note, that no other third party
                  rights exist in respect of the Promissory Note, it possesses
                  the original Promissory Note and that it is entitled to enter
                  into and perform the provisions of this Prepayment Agreement.







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2        COMPLETION

         2.1      Completion of the parties' obligations hereunder shall take
                  place at the offices of the Maker or such other place as the
                  parties may in writing agree on the Completion Date whereupon:

                  (a)      the Maker shall pay the Prepayment Amount by
                           electronic funds transfer to a bank account
                           identified by the Holder to the Maker; and

                  (b)      the Holder shall deliver to the Maker the original
                           Promissory Note marked "Satisfied in Full."

         2.2      Payment by the Maker to the Holder of the Prepayment Amount
                  shall constitute an absolute discharge in favour of the Maker
                  of all liabilities, obligations, amounts, interest, costs,
                  claims and expenses whatsoever and whensoever arising on its
                  part or against it under the terms of the Promissory Note.

3        GOVERNING LAW

         This Prepayment Agreement may be signed in separate counterparts in the
         same form. It shall be governed by and construed in accordance with the
         internal laws (and not the choice of law rules) of the Commonwealth of
         Massachusetts.

IN WITNESS WHEREOF this Prepayment Agreement has been duly executed and
delivered as an instrument under seal as of the date first above written.

SIGNED by                                )
David Robert Chellingsworth              )    /s/ D. R. Chellingsworth
duly authorised for and on behalf of     )    ----------------------------
INNOVATIVE TECHNOLOGIES                  )
GROUP plc in the presence of:            )
Ian R. Metcalfe                          )    /s/ Ian R. Metcalfe
Solicitor, Wragg & Co.                   )    ----------------------------
                                    



POLYMEDICA CORPORATION



BY: /s/ Steven J. Lee
    -------------------------------------------
    NAME: Steven J. Lee
    TITLE: Chairman and Chief Executive Officer



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