Exclusive License Contract

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                                                                   EXHIBIT 10.39

                           EXCLUSIVE LICENSE AGREEMENT

This Exclusive License Agreement (this "AGREEMENT") entered into as of the 14th
day of October, 2005 by and between MEMORY PHARMACEUTICALS CORP., a Delaware
corporation, having its principal place of business at 100 Philips Parkway,
Montvale, New Jersey 07645 ("MEMORY"), and AMGEN INC., a Delaware corporation,
having its principal place of business at One Amgen Center Drive, Thousand Oaks,
California 91320 ("AMGEN").

      Whereas, Memory owns all right title and interest in and to the patents
and patent applications set forth on Schedule 1 hereto (the "LICENSED PATENTS");

      Whereas, Amgen and Memory are parties to that certain Collaboration and
License Agreement dated October 14, 2005 (the "LICENSE AGREEMENT");

      Whereas, Memory desires to grant Amgen an exclusive license to the
Licensed Patents on the terms and conditions set forth i