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                                                                   EXHIBIT 10.30


                      SECOND AMENDMENT TO LICENSE AGREEMENT


         THIS SECOND AMENDMENT ("Amendment") is entered into, effective as of
October 1, 1996, on this 24th day of September, 1996 by and between MULTIPLE
PEPTIDE SYSTEMS, INC., a California corporation ("MPS"), and MAGAININ
PHARMACEUTICALS INC., a Delaware corporation formerly known as Magainin Sciences
Inc. ("Magainin").

                                   BACKGROUND

         A.   MPS and Magainin entered into an Agreement, dated as of November 
4, 1988 (the "Original Agreement"), pursuant to which, among other things, MPS
granted to Magainin certain license rights, as more fully described in the
Original Agreement. MPS and Magainin entered into a First Amendment to
Agreement, dated as of February 1, 1990 (the "First Amendment"), pursuant to
which the parties amended and restated Section 5.1 of the Original Agreement.
The Original Agreement, as amended by the First Amendment, is referred to herein
as the "Agreement."

         B.   Pursuant to a certain Stock Issuance Agreement, dated as of even
dated herewith (the "Stock Issuance Agreement"), between Magainin and Houghten
Pharmaceuticals Inc. ("Houghten"), Magainin has agreed to issue to Houghten
275,000 shares of Magainin's common stock, par value $.002 per share, in
consideration for MPS's agreement to make certain amendments to the Agreement,
as implemented pursuant to this Amendment.

         C.   Capitalized terms used but not defined herein shall have the
respective meanings assigned to such terms in the Agreement.

         NOW, THEREFORE, in consideration of the premises and of the mutual
covenants and promises contained in the Stock Issuance Agreement and in this
Amendment, and for other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the parties hereby agree as
follows, effective as of the date of this Amendment:

         1.   Magainin's license rights under Section 2.1 of the Agreement,
insofar as they relate to the Licensed Product that is Magainin's topical
anti-infective product known as MSI-78, for which a trademark application has
been filed for the name "Cytolex(TM)" ("MSI-78"), are and shall be fully-paid
and royalty-free. Accordingly, with respect to the Licensed Product that is
MSI-78, (a) the provisions of Article III of the Agreement shall not be
applicable, (b) neither Magainin nor any of its sublicensees shall owe any
royalty or other payment obligation to MPS, The Scripps Research Institute, a
successor to Scripps Clinic and Research Foundation ("Scripps"), or any of their
respective successors or assigns under Sections 2.2 or 5.1 of the Agreement, and
(c) neither Magainin nor any of its sublicensees shall have any reporting
obligation to MPS, Scripps or any of


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their respective successors or assigns under Sections 2.2 or 5.1 of the
Agreement. The foregoing shall not be deemed to relieve Magainin of any of its
payment obligations under Sections 4.2, 4.3, 4.4, 12.2 and 12.9 and Article VIII
of the Agreement.

         2. Notwithstanding the provisions of Section 5.1 or any other provision
of the Agreement to the contrary, Magainin shall have the right to grant
sublicenses to any party with respect to any of its rights under the Agreement
relating to the Licensed Product that is MSI-78 without having to notify or
obtain the prior consent of MPS, Scripps or any of their respective successors
or assigns.

         3. The words "as amended" are hereby added at the end of Section 1.10
of the Agreement.

         4. MPS and Magainin acknowledge and agree that Magainin has fulfilled
its commercial development obligations under Section 4.1 of the Agreement
insofar as they relate to MSI-78. However, MPS and Magainin each acknowledge
MPS's interest in being kept advised of Magainin's continuing efforts with
respect to Licensed Products. Accordingly, Section 4.1 of the Agreement is
hereby amended and restated to read in its entirety as follows:

         "4.1   Annual Reporting Obligation. Magainin shall keep MPS generally
         informed as to Magainin's development efforts relating to Licensed
         Products, including its efforts, if any, to sublicense the Scripps
         Patent Rights, by delivery to MPS of an annual written report."

         5. Notwithstanding any provision of the Agreement to the contrary, no
exercise by Magainin or any of its sublicensees of any of the license rights set
forth in the Agreement, or in any permitted sublicense thereof, shall be deemed
to be a breach of the provisions of Article IX of the Agreement.

         6. Section 10.1 of the Agreement is hereby amended by adding the
following two sentences to the the end of such Section:

            "Notwithstanding the fact that Magainin's license rights under
            Section 2.1 hereof, insofar as they relate to the Licensed Product
            that is MSI-78, are fully-paid and royalty-free, Magainin
            acknowledges that it continues to have royalty obligations hereunder
            with respect to Licensed Products other than MSI-78. Therefore, the
            term of the license granted hereunder and of this Agreement shall
            continue until they expire pursuant to this Section 10.1 or are
            terminated sooner pursuant to the provisions of this Agreement,
            notwithstanding such fully-paid and royalty-free license rights of
            Magainin with respect to MSI-78."
     

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         7.  Magainin's address for notices under the Agreement, as set forth in
Section 12.10 of the Agreement, is hereby amended and restated as follows:

            "Magainin Pharmaceuticals Inc.
             5110 Campus Drive
             Plymouth Meeting, PA  19462
             Attention: President"

and MPS's address for notices under the Agreement, as set forth in Section 12.10
of the Agreement, is hereby amended and restated as follows:

            "Multiple Peptide Systems, Inc.
             3550 General Atomics Court
             San Diego, CA 92121
             Attention: President

             with a copy to:

             Houghten Pharmaceuticals, Inc.
             3550 General Atomics Court
             San Diego, CA 92121
             Attention: President"

         8.  MPS shall give to Magainin, in the manner specified in Section 
12.10 of the Agreement, a copy of each notice given or received by MPS under the
Scripps Agreement. MPS shall give each such notice to Magainin promptly after
MPS's giving or receipt of such notice.

         9.  MPS hereby represents and warrants to Magainin as of the date 
hereof that:

             (a) MPS has no knowledge of any default or breach by Scripps or MPS
under the Scripps Agreement, or of any event, fact or circumstance which, with
the giving of notice or the passage of time, or both, would constitute such a
default or breach; and

             (b) The execution, delivery and performance by MPS of this 
Amendment, the execution, delivery and performance by Houghten of the Stock
Issuance Agreement, and the execution, delivery and performance by Scripps of
the Second Amendment to License Agreement, dated as of even date herewith,
between Scripps and MPS, which amends the Scripps Agreement, as amended (the
"Second Amendment to Scripps Agreement"), do not and will not (i) conflict with,
or constitute a breach or default under, or require the consent of any third
party under, MPS' charter documents or any material license, loan or other
agreement, contract, commitment or instrument to which MPS is a party or any of
its assets are bound, (ii) violate any provision of law, statute, rule or
regulation or any ruling, writ, injunction, order, judgment or decree of any
court, administrative agency or other governmental body, or (iii) require the
consent, approval or authorization of, or


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notice, declaration, filing or registration with, any third party or any
governmental or regulatory authority. This Amendment and the Second Amendment to
Scripps Agreement have been duly authorized, executed and delivered by MPS and
each represents the valid and binding obligation of MPS.

             The foregoing representations and warranties shall survive the
execution and delivery of this Amendment, the Second Amendment to Scripps
Agreement and the Stock Issuance Agreement and the consummation of the
transactions contemplated by the Stock Issuance Agreement.

         10. From and after the date of the Second Amendment to Scripps
Agreement, MPS and Scripps will not further modify or amend the Scripps
Agreement without the prior written consent of Magainin in each instance.

         11. Except as specifically modified by this Amendment, all of the
provisions of the Agreement are hereby confirmed to be in full force and effect.

         12. This Amendment shall be binding upon, and shall inure to the
benefit of MPS and Magainin and their respective successors and permitted
assigns.

         13. This Amendment may be executed in one or more counterparts, each of
which shall be deemed to be an original as against any party whose signature
appears thereon, but all of which together shall constitute but one and the same
instrument, and shall become binding when any one or more counterparts hereof,
individually or taken together, shall bear the signatures of MPS and Magainin.


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         IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
executed by their authorized representatives as of the date first written above.


                                      MULTIPLE PEPTIDE SYSTEMS, INC.


                                      By:  /s/ Robert S. Whitehead
                                           -------------------------------------
                                           Name: Robert S. Whitehead
                                           Title: President


                                      MAGAININ PHARMACEUTICALS INC.


                                      By:  /s/ Michael R. Dougherty
                                           -------------------------------------
                                           Name: Michael R. Dougherty
                                           Title: Executive Vice President and
                                                       Chief Financial Officer


                                     JOINDER

              Houghten Pharmaceuticals Inc. ("Houghten"), as the holder of all 
of the issued and outstanding shares of capital stock of MPS, hereby joins in
the execution and delivery of this Amendment solely for the purpose of agreeing
to be jointly and severally liable with MPS for any breach of any of the
representations and warranties of MPS in Section 7 of this Amendment.

                                      HOUGHTEN PHARMACEUTICALS INC.


                                      By:  /s/ Robert S. Whitehead
                                           -------------------------------------
                                           Name: Robert S. Whitehead
                                           Title: President

                                      Date: September 24, 1996



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                              CONSENT AND AGREEMENT

                  The Scripps Research Institute, a successor to Scripps Clinic
and Research Foundation ("Scripps"), hereby consents and agrees to the terms,
conditions and provisions of this Amendment and further agrees, represents and
warrants that:

                  (i)   If the Scripps Agreement is terminated for any reason
whatsoever and if at the time of such termination Magainin is not in material
default of the Agreement, as amended by this Amendment, then the Agreement, as
amended by this Amendment, shall become a direct license agreement between
Scripps and Magainin;

                  (ii)  From and after the date of the Second Amendment to
Scripps Agreement, MPS and Scripps will not further modify or amend the Scripps
Agreement without the prior written consent of Magainin in each instance.

                  (iii) Scripps has no knowledge of any default or breach by
Scripps or MPS under the Scripps Agreement, or of any event, fact or
circumstance which, with the giving of notice or the passage of time, or both,
would constitute such a default or breach;

                  (iv)  As of the date hereof, to Scripps' knowledge, each of 
the Scripps Patent Rights is valid and enforceable in accordance with its terms
and there are no pending or any threatened suits, claims, or actions of any type
whatsoever with respect to any of the Scripps Agreement, the Scripps Patent
Rights, the Scripps Technology or the Scripps Invention; and

                  (v)   The execution, delivery and performance by Scripps of 
this Consent and Agreement and the execution, delivery and performance by
Scripps of the Second Amendment to Scripps Agreement do not and will not (A)
conflict with, or constitute a breach or default under, or require the consent
of any third party under, Scripps' charter documents or any material license,
loan or other agreement, contract, commitment or instrument to which Scripps is
a party or any of its assets are bound, (B) violate any provision of law,
statute, rule or regulation or any ruling, writ, injunction, order, judgment or
decree of any court, administrative agency or other governmental body, or (C)
require the consent, approval or authorization of, or notice, declaration,
filing or registration with, any third party or any governmental or regulatory
authority. This Consent and Agreement and the Second Amendment to Scripps
Agreement have been duly authorized, executed and delivered by Scripps and each
represents the valid and binding obligation of Scripps.


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                  (vi)   The foregoing representations and warranties shall
survive the execution and delivery of this Consent and Agreement and the Second
Amendment to Scripps Agreement.


                                    THE SCRIPPS RESEARCH INSTITUTE


                                    By:  /s/ Arnold LaGuardia
                                         ---------------------------------------
                                         Name: Arnold LaGuardia
                                         Title: Senior Vice President, Treasurer

                                    Date:  September 24, 1996