EXHIBIT 10.13

                      FIRST AMENDMENT TO LICENSE AGREEMENT

      THIS FIRST AMENDMENT TO LICENSE AGREEMENT (the "AMENDMENT") is entered
into as of July 7, 2003 (the "AMENDMENT EFFECTIVE DATE"), between ALGORX
PHARMACEUTICALS, INC., a Delaware corporation ("ALGORX"), and POWDERJECT
RESEARCH LTD., an English corporation (" POWDERJECT").

                                    RECITALS

      WHEREAS, AlgoRx and PowderJect entered into a License Agreement effective
as of March 22, 2002 ( the "LICENSE AGREEMENT"), pursuant to which PowderJect
has granted to AlgoRx a license under certain intellectual property rights
relating to needleless powder injection, including, without limitation, the
delivery of products into the skin, and improvements thereof to discover,
develop, manufacture, and commercialize certain drug products;

      WHEREAS, pursuant to the License Agreement, PowderJect has the ability to
designate certain drug products as PowderJect Named Products, and has exclusive
rights under AlgoRx's improvements to the needleless powder injection
technology licensed to AlgoRx by PowderJect to discover, develop, manufacture,
and commercialize such PowderJect Named Products;

      WHEREAS, the parties desire to amend the License Agreement to modify
AlgoRx's diligence obligations with respect to Cytokine Drugs and to clarify
AlgoRx's reporting obligations;

      NOW, THEREFORE, PowderJect and AlgoRx hereby agree that the License
Agreement shall be amended, effective as of the Amendment Effective Date, as
provided below:

      1.    All capitalized terms used but not otherwise defined herein shall
have the meanings ascribed to such terms in the License Agreement.

      2.    Section 2.9(b) of the License Agreement shall be deleted in its
entirety and replaced with the following new Section 2.9(b):

      2.9(b) CYTOKINE DRUGS. AlgoRx agrees that AlgoRx and/or its Affiliates or
      licensees shall spend an aggregate of at least $1,000,000 on funding
      active research and development efforts on at least one Licensed Product
      that is a Cytokine Drug during the period extanding from the Amendment
      Effective Date and the two (2) year anniversary of the Amendment Effective
      Date. For the avoidance of doubt, the $1,000,000 minimum aggregate
      research and development funding agreed herein expressly excludes any
      research and/or development funding, costs, liabilities or expenses
      incurred or accrued prior to the Amendment Effective Date. Thereafter,
      AlgoRx agrees that AlgoRx and/or its Affiliates or licensees shall
      spend an aggregate of at least $1,000,000 on funding active research
      and development efforts on at least one Licensed Product that is a
      Cytokine Drug during each 12-month period commencing on the two (2) year
      anniversary of the Amendment Effective Date and expiring on the five (5)
      year anniversary of the Amendment Effective Date. If AlgoRx does not meet
      any of its funding obligation under this Section, then thereafter the
      Cytokine Drugs shall be included within the definition of the term
      Selectable Products in Section 1.36 above.



      3.    Section 2.9(c) of the License Agreement shall be deleted in its
entirety and replaced with the following new Section 2.9(c):

      2.9(c) REPORTS. AlgoRx shall keep PRL reasonably informed of AlgoRx's and
      its sublicensees' efforts under Sections 2.9(a) and 2.9(b), and upon PRL's
      request (no more often than once per year), shall provide PRL with a
      written report summarizing the status of such efforts.

      4.    Except as amended hereby, the Agreement shall remain in full force
and effect.

      5.    This Amendment may be executed in one or more counterparts, each of
which shall be an original, and all of which shall constitute together the same
document.

      IN WITNESS WHEREOF, the parties have caused this Amendment to be executed:

ALGORX PHARMACEUTICALS INC.                         POWDERJECT RESEARCH LIMITED

By: /s/ Gordon M. Saul                              By: /s/ C.S.W. Swingland
    ------------------------                            ------------------------
Name: Gordon M. Saul                                Name: C.S.W. Swingland
Title: Vice President                               Title: Director

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