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                                                                   Exhibit 10.21

                                 AMENDMENT NO. 2
                            TO THE LICENSE AGREEMENT
                                     BETWEEN
                         THE TEXAS A&M UNIVERSITY SYSTEM
                                       AND
                                 INHIBITEX, INC.

         This amendment ("Amendment No. 2") is made and entered into by and
between The Texas A&M University System (hereinafter "SYSTEM") with principal
offices in College Station, Texas, and Inhibitex, Inc. (hereinafter
"INHIBITEX"), a Delaware Corporation, having a principal place of business in
Alpharetta, Georgia, parties to the License Agreement dated February 4, 2000,
and Amendment No. 1.

                                   WITNESSETH:

         WHEREAS, the parties have entered into a License Agreement regarding
certain intellectual property related to Extracellular Matrix Binding Proteins;
and

         WHEREAS, the original License Agreement between the parties provides
that INHIBITEX return rights in individual technologies that INHIBITEX fails to
devote reasonable business efforts to the development and commercialization of
certain technology or products claimed in one or more of the patents comprising
PATENT RIGHTS; and

         WHEREAS, SYSTEM understands the principles of patent portfolio
management; and

         WHEREAS, INHIBITEX desires to modify the License Agreement in regard
to its return of rights in individual technologies; and

         WHEREAS, INHIBITEX also desires to modify the License Agreement in
regards to specific sublicensee obligations; and

         WHEREAS, SYSTEM agrees to make such modifications.

         NOW THEREFORE, the parties agree that the License Agreement of February
4, 2000 is hereby amended as follows:

1.       DELETE paragraph 3.01 in its entirety.

2.       ADD a new paragraph 3.01 as follows:

         3.01     Commercial Development and Sales. In consideration of the
                  license grant made to INHIBITEX by SYSTEM herein, INHIBITEX
                  agrees to use commercially reasonable efforts to accomplish
                  commercial development of LICENSED PRODUCTS. INHIBITEX or its
                  sublicensee(s) shall record first NET SALES no later than
                  December 31, 2006, unless failure to reach this development
                  milestone is due to unanticipated or unexpected commercial
                  circumstances, such as but not limited to unforeseen delays in
                  U.S. Government regulatory approval; or unexpected technical,
                  manufacturing scale up, clinical trial or regulatory issues.

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                  Once product sales begin, INHIBITEX shall record NET SALES
                  every consecutive Calendar Year.

3.       ADD new sentences to the end of paragraph 4.01 as follows:

         4.01     For example only and by way of clarification, the parties
                  agree that fees attributable to PATENT RIGHTS shall not
                  include reimbursements by a sublicensee to INHIBITEX of its
                  patent expenses or development expenses and shall not include
                  payments made to INHIBITEX by a sublicensee for achievement of
                  regulatory milestones with the FDA or similar foreign
                  governmental agencies. Payments made to INHIBITEX for
                  achievement o(pound) progress in patent prosecution, such as
                  issuance of a patent application shall be fees attributable to
                  PATENT RIGHTS.

4.       ADD a new sentence to the end of paragraph 7.06 as follows:

         Diligence respecting one or more patent applications or patents within
         the PATENT RIGHTS would constitute diligence as to the PATENT RIGHTS as
         a whole.

         EXCEPT as provided herein, all terms and conditions of the License
Agreement and Amendment No. 1 remain unchanged and in full force and effect.

         IN WITNESS WHEREOF, the parties have caused this Amendment No. 2 to
become effective on the date executed below by the last signatory to this
Amendment.

INHIBITEX, INC.                          THE TEXAS A&M UNIVERSITY SYSTEM

By:     /s/ William D. Johnston          By:     /s/ T.D. Kale
      ---------------------------              -----------------------------
            William D. Johnston                       Tom D. Kale
             President & CEO                          Vice Chancellor for
                                                      Business Services

Date: 4/16/02                            Date: 4/29/02

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