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                                                                   EXHIBIT 10.93
                         AMENDMENT TO LICENSE AGREEMENT

         This Amendment to License Agreement ("Amendment") is entered into as of
January 1, 2001 by and between Mitsubishi-Tokyo Pharmaceuticals, Inc., with its
principal offices at 2-6, Nihonbashi-Honcho 2-chome, Chuo-Ku, Tokyo 103-8405,
Japan, a successor in interest to Mitsubishi Chemical Corporation ("Mitsubishi")
and Triangle Pharmaceuticals, Inc., with its principal offices located at 4
University Place, 4611 University Drive, Durham, North Carolina 27707
("Triangle") and amends certain terms of that certain License Agreement, dated
as of June 17, 1997, between Mitsubishi and Triangle (the "Agreement").
Capitalized terms not defined herein shall have the meanings given them in the
Agreement.
                                    RECITALS
         A. Mitsubishi and Triangle have previously entered into the Agreement,
pursuant to which Mitsubishi has licensed certain patent rights and know-how to
Triangle relating to a compound known as MKC-442..
         B. As part of its diligence efforts in respect of MKC-442, Triangle is
required to use its best efforts to file an NDA for a Licensed Product in at
least one Major Market Country     ***     , subject to certain extensions
permitted by the Agreement.
         C. Mitsubishi and Triangle desire to amend certain terms of the
Agreement relating to such due diligence time limit.

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         NOW, THEREFORE, for good and valuable consideration, Mitsubishi and
Triangle hereby agree as follows:

         1.       AMENDMENTS. Subsection 6.2(a) of the Agreement is hereby
                  deleted in its entirety and replaced as follows:

                      "(a) files in at least one Major Market Country what it
                      reasonably believes to be a complete NDA for a Licensed
                      Product with the appropriate regulatory agency within ***
                      after the Effective Date; provided, however, said ***
                      period shall be subject to up to *** exensions of *** each
                      at Triangle's election by payment to Mitsubishi of a sum
                      of *** for each such *** extension;"

         2.       GENERAL TERMS. The Agreement, as amended by this Amendment,
                  constitutes the entire agreement between Mitsubishi and
                  Triangle or regarding the subject matters contained therein
                  and herein. In the event of any conflict between the
                  provisions of the Agreement and this Amendment, the provisions
                  of this Amendment shall govern and control. This Amendment
                  shall be governed by, and construed in accordance with, the
                  laws of the State of New York without regard to its conflicts
                  of laws principles. This Amendment may be executed in any
                  number of counterparts, each of which shall be deemed an
                  original and all of which shall constitute one and the same
                  instrument. If any provision of this Amendment is for any
                  reason held to be ineffective, unenforceable or illegal, such
                  condition shall not affect the validity or enforceability of
                  any of the remaining portions hereof; provided, further, that
                  the parties shall


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                  negotiate in good faith to replace any ineffective,
                  unenforceable or illegal provision with an effective
                  replacement as soon as is practical.

         IN WITNESS WHEREOF, Mitsubishi and Triangle have each executed this
Amendment through an authorized officer as of the date written below.


                                    MIUTSUBISHI-TOKYO PHARMACEUTICALS, INC.

                                    By: /s/ Ryuichi Tomizawa
                                    Its: President
                                    Date: January 9, 2001


                                    TRIANGLE PHARMACEUTICALS, INC.

                                    By: /s/ Chris A Rallis
                                    Its: President
                                    Date: January 3, 2001