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                                                                    Exhibit 10.5


                        SECOND AMENDED AND RESTATED NOTE

$6,000,000                                                Boston, Massachusetts
                                                          July 26, 1996

         FOR VALUE RECEIVED, Alkermes, Inc. a Pennsylvania corporation and its
wholly owned subsidiary Alkermes Investments, Inc., a Delaware corporation,
(together, "Makers") hereby promise to pay, jointly and severally, to the order
of The Sumitomo Bank, Limited, a Japanese banking corporation ("Bank"), without
counterclaim, offset or deduction, the principal sum of SIX MILLION DOLLARS
($6,000,000), with interest, as specified in the Amended Loan Agreement (as
defined below).  Each payment of principal shall first be applied to any
outstanding principal under the First Tranche until such loan is paid in full,
and then any remaining amount shall be applied to the principal outstanding
under the Second Tranche.

         Makers shall make all payments hereunder in lawful money of the United
States and in immediately available funds to Bank's account by means of a wire
transfer addressed as follows:  The Sumitomo Bank, Limited, Chicago Branch, ABA
071001850, through the Federal Reserve Bank of Chicago, Reference:  Alkermes,
Inc.

         All agreements between Makers and Bank, whether now existing or
hereafter arising, are hereby limited so that in no event shall the interest
charged hereunder or agreed to be paid to Bank exceed the maximum amount
permissible under applicable law.  Bank shall be entitled to amortize, prorate
and spread throughout the full term of this Note all interest paid or payable
so that the interest paid does not exceed the maximum amount permitted by law.

         This Second Amended and Restated Note amends, restates and replaces in
its entirety that certain Amended and Restated Note dated December 29, 1995 in
the original principal amount of $6,000,000 issued by Makers in favor of The
Daiwa Bank, Limited, which assigned its interest therein to Bank on February 2,
1996.  This Second Amended and Restated Note is the Second Amended and Restated
Note referred to in the Omnibus Amendment to Loan Documents dated as of the
date hereof between Makers, Bank and the Sumitomo Bank of New York Trust
Company, which amends that certain Loan Agreement, dated as of December 30,
1993, between Makers and Bank, as previously amended (as amended, modified and
supplemented through and including the date hereof, including the amendments
contained in Omnibus Amendment to Loan Documents, the "Amended Loan Agreement")
and is subject to all of the terms and conditions, representations and
warranties thereof, including the rights of prepayment and the rights of
acceleration of maturity.  Terms used herein have the meanings assigned to
those terms in the Amended Loan Agreement, unless otherwise defined herein.
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         Makers shall pay all reasonable fees, costs and expenses, including
reasonable attorneys' fees, incurred by Bank in the preparation and negotiation
of this Second Amended and Restated Note and the Amended Loan Agreement and in
the enforcement or attempt to enforce any of Makers' obligations hereunder not
performed when due, whether or not any legal action is actually filed,
litigated or prosecuted to judgment of award.  This Second Amended and Restated
Note shall be governed by and construed in accordance with the laws of the
Commonwealth of Massachusetts.

         Time is of the essence in the performance of the obligations evidenced
by this Second Amended and Restated Note.  All parties to this Second Amended
and Restated Note waive presentment, notice of dishonor, protest and all other
demands and notices.

         If this Second Amended and Restated Note is destroyed, lost or stolen,
Makers shall deliver a new note to Bank on the same terms and conditions as
this Note, with all appropriate schedules annexed thereto, in substitution of
the prior Second Amended and Restated Note.  Bank shall furnish to Makers
reasonable evidence that the Second Amended and Restated Note was destroyed,
lost or stolen and any security or indemnity that may be reasonably required by
Makers in connection with the replacement of the Second Amended and Restated
Note.

         Executed under seal as of the day and date referred to above.

                                                  ALKERMES, INC., a Pennsylvania
                                                  corporation


ATTEST:                                           By: /s/ Michael Landine
                                                      --------------------------

                                                  Name:  Michael J. Landine
Patricia L. Allen                                 Title:  Senior VP & CFO


                                                  ALKERMES INVESTMENTS, INC.,
                                                  a Delaware corporation


ATTEST:                                           By: /s/ Michael Landine
                                                      --------------------------

                                                  Name:  Michael J. Landine
Patricia L. Allen                                 Title:  VP & CFO



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