Exhibit 10.3

AMENDMENT TO OPTION AGREEMENT

Amendment (the “Amendment”) to Option Agreement No.              (the “Option
Agreement”), dated as of April 9, 2007, by and between              (the
“Optionee”) and FermaVir Pharmaceuticals, Inc. (the “Company”).  All capitalized
terms used herein and not otherwise defined herein shall have the respective
meanings provided to such terms in the Option Agreement.

W I T N E S S E T H :

WHEREAS, the parties wish to amend the Option Agreement to (i) immediately vest
all option grants under the Option Agreement and (ii) change the expiration date
of such Options to the earlier of (a) three (3) years after the date on which
the Optionee’s service on the Board of Directors of Inhibitex, Inc. terminates
and (b) January 31, 2017.

NOW, THEREFORE, in consideration of the mutual covenants set forth herein and
other good and valuable consideration, the receipt and sufficiency of which are
hereby acknowl­edged, the parties hereto, intending to be legally bound, hereby
agree as follows:

ARTICLE ONE

AMENDMENT TO OPTION AGREEMENT

SECTION 1.1  Amendment to Option Agreement.  By executing this Agreement, the
Company and Optionee hereby agree and acknowledge that Section 1 of the Option
Agreement is hereby replaced in its entirety with the following:

“Vesting, Term and Exercise of Option.  Subject to the provisions of this
Agreement, this option may be exercised for up to the number of vested Optioned
Shares by you or the representative of your estate on or prior to the earlier of
(i) three (3) years after the date on which the Optionee’s service on the Board
of Directors of Inhibitex, Inc. terminates and (ii) January 31, 2017.  The
Optioned Shares shall be vested immediately.”

ARTICLE TWO

MISCELLANEOUS

SECTION 2.1  COUNTERPARTS.  THIS AGREEMENT MAY BE EXECUTED IN ANY NUMBER OF
COUNTERPARTS AND BY THE DIFFERENT PARTIES HERETO ON SEPA­RATE COUNTERPARTS, EACH
OF WHICH COUNTERPARTS WHEN EXECUTED AND DELIVERED (INCLUDING DELIVERY BY WAY OF
FACSIMILE) SHALL BE AN ORIGINAL, BUT ALL OF WHICH SHALL TOGETHER CONSTITUTE ONE
AND THE SAME INSTRUMENT.

SECTION 2.2  GOVERNING LAW.  THIS AGREEMENT SHALL BE GOVERNED BY, AND CONSTRUED
AND ENFORCED IN ACCORDANCE WITH, THE INTERNAL LAWS OF THE STATE OF NEW YORK,
EXCLUDING CONFLICT OF LAW PRINCIPLES THAT WOULD CAUSE THE APPLICATION OF LAWS OF
ANY OTHER JURISDICTION.

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SECTION 3.3  EFFECTIVE DATE.  THIS AGREEMENT SHALL BECOME EFFECTIVE (THE
“EFFECTIVE DATE”) AS OF THE DATE OF THIS AGREEMENT.

SECTION 3.4  EFFECT OF AMENDMENT.  FROM AND AFTER THE EFFECTIVE DATE, THE 
OPTION AGREEMENT AND ALL REFERENCES TO THE OPTION AGREEMENT PURSUANT TO THE
OPTION AGREEMENT AND THE OTHER DOCUMENTS REFERENCED THEREIN SHALL BE DEEMED TO
BE REFERENCES TO THE OPTION AGREEMENT AS MODIFIED HEREBY.  THIS AGREEMENT IS
LIMITED AS SPECIFIED AND SHALL NOT CONSTITUTE A MODIFI­CATION, AMENDMENT,
ACCEPTANCE OR WAIVER OF ANY OTHER PROVISION OF THE OPTION AGREEMENT OR ANY OTHER
DOCUMENT REFERENCED THEREIN OR HEREIN.

SECTION 3.5  HEADINGS.  THE ARTICLE, SECTION AND SUBSECTION HEADINGS IN THIS
AGREEMENT ARE FOR CONVENIENCE ONLY AND SHALL NOT CONSTITUTE A PART OF THIS
AGREEMENT FOR ANY OTHER PURPOSE AND SHALL NOT BE DEEMED TO LIMIT OR AFFECT ANY
OF THE PROVISIONS HEREOF.

SECTION 3.6  FURTHER ASSURANCES.  FROM AND AFTER THE DATE OF THIS AGREEMENT,
UPON THE REQUEST OF ANY PARTY HERETO, EACH PARTY SHALL EXECUTE AND DELIVER SUCH
INSTRUMENTS, DOCUMENTS AND OTHER WRITINGS AS MAY BE REASONABLY NECESSARY OR
DESIRABLE TO CONFIRM AND CARRY OUT AND TO EFFECTUATE FULLY THE INTENT AND
PURPOSES OF THIS AGREEMENT.

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IN WITNESSES WHEREOF, the parties hereto have caused their duly authorized
officers to execute and deliver this Agreement as of the date first above
written.

FERMAVIR PHARMACEUTICALS, INC.

 

 

By:

 

 

 

Name:

 

Title:

 

 

 

 

 

 

 

 

 

:

 

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