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                                                                   Exhibit 10.8


                                 PROMISSORY NOTE

$5,000,000.00                                             Boston, Massachusetts
                                                             September 27, 1996

     FOR VALUE RECEIVED, the undersigned Alkermes, Inc., a Pennsylvania
corporation ("Alkermes") and Alkermes Controlled Therapeutics Inc. II, a
Pennsylvania corporation and a wholly-owned subsidiary of Alkermes ("ACT II")
(Alkermes and ACT II being hereinafter referred to collectively as the
"Borrowers" and individually as a "Borrower") hereby jointly and severally
promise to pay to the order of FLEET NATIONAL BANK (the "Bank") the principal
amount of Five Million and 00/100 ($5,000,000.00) Dollars ("Principal"), with
interest, at the rate hereinafter set forth, on the daily balance of all unpaid
Principal, from the date hereof until payment in full of all Principal and
interest hereunder.

     Interest on all unpaid Principal shall be due and payable monthly in
arrears, on the first day of each month commencing on the first such date after
the date of this note and continuing on the first day of each month thereafter
and on the date of payment of this note in full, at the rate of 8.54% per annum
(computed on the basis of a year of three hundred sixty (360) days for the
actual number of days elapsed). Overdue Principal shall bear interest at a rate
per annum which at all times shall be equal to the sum of (i) two (2%) percent
per annum plus (ii) the per annum rate otherwise payable under this note (but in
no event in excess of the maximum rate permitted by then applicable law),
compounded monthly and payable on demand. If the entire amount of any required
Principal and/or interest is not paid within ten (10) days after the same is
due, the Borrowers shall pay (and shall be jointly and severally obligated to
pay) to the Bank a late fee equal to five percent (5%) of the required payment,
provided that such late fee shall be reduced to three percent (3%) of any
required Principal and interest that is not paid within fifteen (15) days of the
date it is due if this note is secured by a mortgage on an owner-occupied
residence of 1-4 units.

     Principal shall be repaid in fifty-nine (59) equal consecutive monthly
installments (each in an amount equal to $83,333.33) commencing on November 1,
1996 and continuing on the first day of each month thereafter through and
including September 1, 2001, plus a sixtieth (60th) and final payment due on
October 1, 2001 in an amount equal to all then remaining Principal and all
interest accrued but unpaid thereon. The Borrowers may at any time and from time
to time prepay all or any portion of said Principal; provided that each such
prepayment of Principal shall be accompanied by (i) payment of all interest
under this note accrued but unpaid to the date of prepayment and (ii) the
"Make-Whole Amount", if any, required by the provisions of Section 1.6 of that
certain letter agreement of even date herewith (the "Letter Agreement") among
the Bank, the Borrowers and Alkermes Controlled Therapeutics, Inc., a
wholly-owned subsidiary of Alkermes. Any partial prepayment of Principal shall
be applied against Principal installments (including the final installment of
Principal) thereafter coming due, in inverse order of normal maturity.


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     Payments of both Principal and interest shall be made, in immediately
available funds, at the office of the Bank located at 75 State Street, Boston,
Massachusetts 02109, or at such other address as the Bank may from time to time
designate.

     Each of the undersigned Borrowers irrevocably authorizes the Bank to make
or cause to be made, on a schedule attached to this note or on the books of the
Bank, at or following the time of receiving any payment of Principal, an
appropriate notation reflecting such transaction and the then aggregate unpaid
balance of Principal. Failure of the Bank to make any such notation shall not,
however, affect any obligation of any Borrower hereunder or under the Letter
Agreement. The Principal balance of this note, as recorded by the Bank from time
to time on such schedule or on such books, shall constitute presumptive evidence
of the unpaid principal amount of the term loan represented hereby.

     Each Borrower hereby (a) waives notice of and consents to any and all
advances, settlements, compromises, favors and indulgences (including, without
limitation, any extension or postponement of the time for payment), any and all
receipts, substitutions, additions, exchanges and releases of collateral, and
any and all additions, substitutions and releases of any person primarily or
secondarily liable, (b) waives presentment, demand, notice, protest and all
other demands and notices generally in connection with the delivery, acceptance,
performance, default or enforcement of or under this note, and (c) agrees to
pay, to the extent permitted by law, all reasonable costs and expenses,
including, without limitation, reasonable attorneys' fees, incurred or paid by
the Bank in enforcing this note and any collateral or security therefor, all
whether or not litigation is commenced.

     This note is secured, inter alia, by a Mortgage and Security Agreement of
even date herewith (the "Mortgage") given by ACT II to the Bank and encumbering
real estate in Wilmington, Clinton County, Ohio. This note is the "Ohio Term
Note" referred to in the Mortgage and in the Letter Agreement and is entitled to
benefits thereof. This note is subject to prepayment under the conditions set
forth in the Letter Agreement, with the Make-Whole Amount, if any, required by
the Letter Agreement consequent upon such prepayment. The maturity of this note
may be accelerated upon the occurrence of an Event of Default, as provided in
the Letter Agreement and/or in the Mortgage. This note is the joint and several
obligation of each of the Borrowers.

     Executed, as an instrument under seal, as of the day and year first above
written.


CORPORATE SEAL                                  ALKERMES, INC.

ATTEST:

                                                By /s/ Michael Landine
/s/ Patricia L. Allen                             -----------------------------
---------------------------                     Name: Michael Landine
Assistant Secretary                             Title: Senior VP and CFO


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CORPORATE SEAL                                  ALKERMES CONTROLLED
                                                 THERAPEUTICS INC. II

ATTEST:

                                                By /s/ Michael Landine
/s/ Patricia L. Allen                             -----------------------------
---------------------------                     Name: Michael Landine
Assistant Secretary                             Title: Vice President




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