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                                                                 EXHIBIT 10.9(c)
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           Amendment No. 3 to Research, License and Royalty Agreement
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     This Amendment No. 3 to Research, License and Royalty Agreement (the
"Amendment") effective as of November 21, 1997, is entered into by and between
Pharmacopeia, Inc. ("Pharmacopeia") and Berlex Laboratories, Inc. ("Berlex"),
and amends that certain Research, License and Royalty Agreement entered into by
Pharmacopeia and Berlex effective as of February 15, 1995 (the "Agreement"), as
amended by Amendment No. 1 to Research, License and Royalty Agreement effective
as of November 27, 1996 and Amendment No. 2 to Research, License and Royalty
Agreement effective as of June 30, 1997.


1.   All capitalized terms not defined in this Amendment shall have the meanings
     given to them in the Agreement, as amended.

2.   The following new Sections 1.49 and 1.50 are added following Section 1.48:

     1.49  "Outside Compound" is defined in Section 4.9(b).

     1.50  "Outside Target" means any target against which Pharmacopeia screens
     one or more of the Focused Libraries other than (i) the Initial Berlex
     Target or (ii) the Additional Berlex Target.

3.  Subsection 4.5(a) is amended to read in its entirety as follows:

        (a) subject to the terms of Section 4.7, an exclusive (even as to
     Pharmacopeia) worldwide, royalty-bearing license under the Developed
     Technology to make, have made, use and sell compounds in Focused Libraries,
     Lead Compounds, Development Compounds, Products and Other Products in and
     outside the Field;

4.  Subsection 4.5(d) is amended to read in its entirety as follows:

        (d) subject to the terms of Section 4.7, an exclusive (even as to
     Pharmacopeia) worldwide, royalty-bearing license under the Pharmacopeia
     Base Technology to make, have made, use and sell compounds in Focused
     Libraries, Lead Compounds, Development Compounds, Products and Other
     Products in and outside the Field.
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5.  The following language shall be added to the end of Section 4.7:

     Notwithstanding any contrary provision of this Agreement, Berlex also
     grants to Pharmacopeia a co-exclusive (with Berlex) worldwide license under
     the Berlex Base Technology and Berlex's interest in the Developed
     Technology to make, have made, use and sell any compounds in the Focused
     Libraries outside the Field on the terms and conditions set forth in
     Sections 4.9 and 4.15 below, with the right to grant sublicenses in
     accordance with Section 4.15 below.

6.  Section 4.9 is amended to read in its entirety as follows:

     4.9  Use of Focused Libraries.
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     (a) Limitation on Use.  For a period from the end of the Term until
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     expiration of the last to expire issued Live Claim which claims Focused
     Libraries, Lead Compounds, Development Compounds, Products or Other
     Products or, in the case of a Live Claim in a pending patent application,
     until the earlier of (i) abandonment cancellation, withdrawal, or
     disclaiming of such Live Claim or (ii) the [***] anniversary of filing such
     patent application or, if a parent of such patent application exists, the
     [***] anniversary of the earliest such parent application, Pharmacopeia may
     not use the Focused Libraries, Lead Compounds, Development Compounds,
     Products and Other Products for any purpose except (A) Pharmacopeia's
     Internal Research Purposes and (B) screening against  Outside Targets as
     set forth in Section 4.9(b) below.  "Internal Research Purposes" means
     Pharmacopeia's sole, internal use for which it is not receiving payment
     from any Third Party, without the right to license or disclose to a Third
     Party any results of such use for any purpose without the prior, express
     written consent of Berlex.  Pharmacopeia agrees not to transfer such
     Focused Libraries, substances therein, Lead Compounds or Development
     Compounds to any Third Party in connection with such use for Internal
     Research Purposes.

     (b) Screening Against Outside Targets.  Pharmacopeia may use the Focused
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     Libraries including those listed on Exhibit A hereto, for purposes of
     screening against Outside Targets to identify Outside Compounds. As used
     herein, "Outside Compound" shall mean a compound that (i) is identified
     through Pharmacopeia's screening of the Focused Libraries pursuant to this
     Section 4.9(b), and (ii) has activity against an Outside Target; provided,
     however, that compounds which are Lead Compounds or Development Compounds
     shall not be Outside Compounds.  Pharmacopeia may commercialize such
     Outside Compounds as set forth in Section 4.15 below.



*** Information omitted and filed separately with the Commission under Rule 
    24b-2

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7.  The following new Section 4.15 is inserted following Section 4.14:

     4.15  Commercialization of Outside Compounds.  In the event that
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     Pharmacopeia desires to commercially exploit an Outside Compound,
     Pharmacopeia may so notify Berlex in writing [***]

     (a) [***] Berlex shall give Pharmacopeia written notice (a "Berlex
     Response") stating whether Berlex desires to [***].  If Berlex states in
     such Berlex Response [***].  If Berlex states in the Berlex Response that
     [***].

     (b) [***] In the event that Berlex and Pharmacopeia [***].  Pharmacopeia
     shall not, [***].


*** Information omitted and filed separately with the Commission under Rule 
    24b-2

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     (c) Third Party Collaboration.  [***]  Pharmacopeia may negotiate with any
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     third party, and enter into with any third party, an agreement concerning
     research and development of such Outside Compound and an exclusive (even as
     to Pharmacopeia and Berlex) royalty-bearing license (or sublicense as the
     case may be) under the Developed Technology and the Pharmacopeia Base
     Technology to make, have made, use, sell, offer to sell, and import
     products containing such Outside Compound or other compounds identified
     through such research and development; provided, however, that Pharmacopeia
     shall pay to Berlex [***] of any non-royalty cash consideration for such
     license actually received by Pharmacopeia from such third party (including
     without limitation up-front payments, premiums on equity, license fees, and
     milestones payments, but excluding all amounts provided to Pharmacopeia in
     the form of loans or compensation for research or development services, or
     other work, performed by Pharmacopeia) and [***] of any cash royalty
     payments actually received by Pharmacopeia from such third party for
     products containing such Outside Compound.

     (d) Restriction on Exploitation of Outside Compounds.  Except as the
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     parties may otherwise agree in writing, Berlex shall not research, develop,
     exploit, sell or commercialize (through licensing, research collaboration,
     or otherwise) any Outside Compound that has been identified to Berlex in an
     Outside Compound Notification received by Berlex other than through an
     agreement with Pharmacopeia pursuant to this Section 4.15, and Pharmacopeia
     shall not exploit, sell or commercialize (through licensing, research
     collaboration, or otherwise) Outside Compounds except as provided in this
     Section 4.15.

8.  The following new Subsection 14.3(e) is inserted following Subsection
    14.3(d):

     (e) Outside Compounds.  It is understood that all agreements, if any,
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     between Pharmacopeia and third parties with respect to research and
     development of Outside Compounds entered into pursuant to Section 4.15, and
     all licenses or sublicenses, if any, granted by Pharmacopeia to a third
     parties in accordance with Section 4.15, shall not be affected by the
     expiration or termination of this Agreement for any reason, and such
     agreements, licenses or sublicenses shall only terminate or expire in
     accordance with their own terms.  Notwithstanding any other provision of
     this Agreement, the right of Pharmacopeia to screen Focused Libraries
     against Outside Targets in accordance with Sections 4.7 and 4.9 and to
     enter into agreements and licenses or sublicenses with respect to Outside
     Compounds as set forth in Section 4.15 shall survive the expiration or
     termination of this Agreement for any reason.


*** Information omitted and filed separately with the Commission under Rule 
    24b-2

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9.   Except as specifically modified or amended hereby, the Agreement shall
     remain in full force and effect and, as modified or amended, is hereby
     ratified, confirmed and approved.  No provision of this Amendment may be
     modified or amended except expressly in a writing signed by both parties
     nor shall any terms be waived except expressly in a writing signed by the
     party charged therewith.  This Amendment shall be governed in accordance
     with the laws of the State of Delaware, without regard to principles of
     conflicts of laws.


     IN WITNESS WHEREOF, each of the parties has executed this Amendment as of
the date indicated on this Amendment.

BERLEX LABORATORIES, INC.            PHARMACOPEIA, INC.

By: /S/ DALE STRINGFELLOW            By:  /S/ JOSEPH A. MOLLICA
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Name:  Dale Stringfellow                  Name:  Joseph A. Mollica, Ph.D.
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Title: Vice President                     Title: Chairman & CEO
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Date:  November 21, 1997                  Date:  November 20, 1997
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