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                                                                   Exhibit 10.38

                            FIRST AMENDMENT TO LEASE

         WHEREAS, NEW BOSTON WILMAR LIMITED PARTNERSHIP (hereinafter referred to
as "Landlord") and ASCENT PEDIATRICS, INC. (hereinafter referred to as "Tenant")
entered into a certain lease of premises located at the building known and
numbered as 187 Ballardvale Street, Wilmington, Massachusetts, and dated
November 21, 1996 (hereinafter referred to as "Lease"); and

         WHEREAS, Landlord and Tenant now desire to amend the Lease.

         NOW THEREFORE, in consideration of the mutual covenants herein
contained, and other good and valuable consideration the receipt and sufficiency
of which are hereby acknowledged by both parties, it is agreed as follows:

         1. Section I of the Lease is amended by inserting the following
language at the end of the second paragraph thereof:

                  "Effective September 15, 1997, the premises shall also include
         approximately 4,542 square feet of net rentable area on the Second
         Floor of the Building, as more particularly shown as the cross-hatched
         area on Exhibit A-1 attached hereto and incorporated herein by
         reference (hereinafter referred to as the "Additional Space")."

         2. Section IV of the Lease is amended by inserting the following
language at the end of the first paragraph thereof:

                  "Effective September 15, 1997, Tenant shall pay rent with
         respect to the Additional Space at the annual rental rates set forth
         below:

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<TABLE>
<CAPTION>

                                                     PER SQUARE FOOT RENTAL RATE
                                                     ---------------------------
<S>                                                            <C>
      September 15, 1997 - September 30, 1998                  $16.50
      October 1, 1998 - September 30, 2000                     $17.00
      October 1, 2000 - February 28, 2002                      $17.50"
</TABLE>

         3. Section V(a) of the Lease is amended by inserting the following
language at the end thereof:


                  "Landlord shall do no work in or to the Additional Space to
         prepare the same for occupancy by Tenant, it being understood and
         agreed that Tenant accepts the same in their "as-is" condition. The
         taking of possession of the Additional Space by Tenant shall be
         conclusive evidence of the acceptance of the Additional Space by Tenant
         and the Additional Space is in good and satisfactory condition, in
         accordance with Landlord's obligations hereunder."

         4. Section XI(c) of the Lease is amended by inserting the following
language at the end thereof:

                  "Effective September 15, 1997, "Tenant's Proportionate Share"
         for taxes shall be eighteen and 20/100 percent (18.2%)."

         5. Section XI(i) of the Lease is amended by inserting the following
language after the first sentence thereof:

                  "Effective September 15, 1997, "Tenant's Proportionate Share
         for Operating Cost Escalation" shall be eighteen and 20/100 percent
         (18.2%)."

         6. Section XLIII of the Lease is amended by inserting the following
language at the end thereof:

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                  "Neither Landlord nor Tenant has dealt with any broker in
         connection with the transaction reflected in this Second Amendment to
         Lease, and each agrees to indemnify and hold the other harmless on
         account of any claims or demands for a brokerage commission as a result
         hereof."

         7. Section XLV of the Lease is amended by inserting the following
language at the end thereof:

                  "On or before September 15, 1997, Tenant shall increase the
         security deposit hereunder by Six Thousand Two Hundred Forty-Five
         Dollars ($6,245)."

         8. The Lease shall be amended by inserting the following language after
Section XLVIII thereof:

                  "SECTION XLIX. RIGHT OF FIRST OFFER. Provided Tenant is not in
         default of its obligations hereunder, Landlord shall provide Tenant
         with written notice (the "Right of First Offer Notice") if during the
         term of this lease that portion of the first floor of the Building and
         containing approximately 4,629 square feet of rentable area, as more
         particularly shown as the cross-hatched area on Exhibit O attached
         hereto and incorporated herein by reference, is or will become
         available for lease (the "First Offer Premises"). The Landlord's Right
         of First Offer Notice to Tenant shall set forth the premises' square
         footage, availability date, term, tenant improvement allowance, if any,
         and rental rate, which rental rate shall reflect the fair market rental
         value for such premises which Landlord would accept from a new tenant
         to lease the Premises as of the stated availability date. Tenant shall
         have five (5) business days following receipt of the Right of First
         Offer Notice to exercise its Right of First Offer, which Right of First
         Offer shall apply only with respect to the entire premises offered, and
         if Tenant shall fail to

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         exercise said Right of First Officer within said five (5) business
         day period, Tenant shall have waived its right to space offered and
         shall have no further right pursuant to this Section XLIX to said
         space for the remainder of the term of this lease, as it may be
         extended. In the event Tenant accepts the offer of any space pursuant
         to this Section XLIX, Landlord and Tenant shall execute an amendment to
         this lease, setting forth the terms and conditions for the lease by
         Tenant of the space so acquired.

                  "Notwithstanding the provisions of this Section XLIX, Landlord
         expressly reserves the right the right to renew, extend, amend or
         modify the lease of the existing tenant with respect to the First Offer
         Premises as it sees fit."

         9. This First Amendment to Lease is contingent upon Landlord entering
into a Lease Termination Agreement with Netcore Systems, Inc., with respect to
the Additional Space, effective September 14, 1997.

         10. Except as modified hereby the Lease is hereby ratified and
affirmed.

         IN WITNESS WHEREOF, the parties have set their hands and seals this
18th day of September 1997.

                                             LANDLORD:

                                             NEW BOSTON WILMAR
                                             LIMITED PARTNERSHIP

                                             By:   New Boston Fund, Inc.
                                                   Its General Partner


                                             By: /s/ Jerome L. Rappaport, Jr.
                                                --------------------------------
                                                   Jerome L. Rappaport, Jr.
                                                   Its President

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                                             TENANT:


                                             ASCENT PEDIATRICS, INC.


                                             By: /s/ Alan R. Fox
                                                --------------------------------
                                                 Its President
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                                   Exhibit A-1



                     [Diagram of floor plan of Second Floor
              of 187 Ballardvale Drive, Wilmington, Massachusetts]



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