Exhibit 4.1


THIS NOTE HAS NOT BEEN REGISTERED UNDER ANY SECURITIES
LAWS, AND MAY NOT BE SOLD OR OTHERWISE DISPOSED OF UNLESS THE COMPANY HAS
RECEIVED A WRITTEN OPINION FROM COUNSEL IN FORM AND SUBSTANCE SATISFACTORY TO
THE COMPANY STATING THAT SUCH TRANSFER IS BEING MADE IN COMPLIANCE WITH ALL
APPLICABLE SECURITIES LAWS.


FERMAVIR PHARMACEUTICALS,
INC.


12% SENIOR SECURED PROMISSORY NOTE


	
  $

  	
   

  	
  New York, New York

  
	
   

  	
   

  	
  April 9, 2007

  



 


FOR VALUE
RECEIVED, the undersigned, FermaVir Pharmaceuticals, Inc., a Florida corporation (the “Company”),
hereby promises to pay to the order of Inhibitex, Inc., a Delaware corporation
(and together with its registered assigns, the “Holders”), the principal sum of            Dollars
($    ,000) on the Maturity Date (as defined below), with
interest on the principal amount of this Note from time to time as provided
herein.


1.                             Note
Purchase Agreement.  This Senior Secured
Promissory Note (this “Note”) is issued pursuant to the Note Purchase Agreement
(the “Note Purchase Agreement”), dated as of April 9, 2007, by and between the
Company and the Purchaser, and is subject to the terms thereof.  This Note, together with any promissory notes
issued pursuant to the Note Purchase Agreement or Sections 11 or 12 hereof, are
hereinafter referred to as the “Notes.” 
The Holders are entitled to the benefits of this Note and the Note
Purchase Agreement, as it relates to this Note, and may enforce the agreements
of the Company contained in this Note and the Note Purchase Agreement and
exercise the remedies provided for in this Note and the Note Purchase Agreement
or otherwise available in respect hereto and thereto.  Capitalized terms used herein and not defined
herein shall have the meanings ascribed to such terms in the Note Purchase
Agreement.  All amounts payable under
this Note shall be in United States dollars, unless otherwise agreed by the
parties.


2.                             Interest.


(a)  Generally.  The Company promises to pay interest (“Interest”)
on the principal amount of this Note at the rate of 12.00% per annum (the “Interest
Rate”).  Interest on this Note shall
accrue from and including             ,
2007 through and until repayment of the principal amount of this Note and
payment of all Interest in full and shall be computed on the basis of the
actual number of days elapsed over a year of 365 days.


(b)  Default Rate of Interest.  Upon
and during the occurrence of an Event of Default (as defined in the Note
Purchase Agreement), this Note shall bear interest, from the date of the
occurrence of such Event of Default until such Event of Default is cured or
waived, payable on demand in immediately available funds, at a rate equal to
the sum of (i) the Interest Rate and (ii) an additional 2.00% per annum (such
sum being referred to herein as the “Default Rate”).












(c)  No Usurious
Interest.  In the event that any
interest rate(s) provided for in this Section 2 shall be determined to be
unlawful, such interest rate(s) shall be computed at the highest rate permitted
by applicable law.  Any payment by the Company
of any interest amount in excess of that permitted by law shall be considered a
mistake, with the excess being applied to the principal amount of this Note
without prepayment premium or penalty; if no such principal amount is
outstanding, such excess shall be returned to the Company.


3.                             Principal.  The outstanding principal and accrued and
unpaid interest under this Note shall become due and payable on the Maturity
Date.  The “Maturity Date” shall mean the
earliest to occur of (a) December 31, 2007, (b) ninety (90) days after the
termination of the Merger Agreement by Parent (as defined therein) pursuant to
Section 7.1(f) thereof, (c) one hundred twenty (120) days after the termination
of the Merger Agreement by the Company pursuant to Section 7.1(e) thereof and
(d) the consummation of an Acquisition Proposal other than the one contemplated
by the Merger Agreement after termination of the Merger Agreement by Parent
pursuant to Section 7.1(c) thereof.


4.                             Redemption.  This Note as well as the rights and
obligations of the Company are subject to the redemption provisions contained
in Section 11.1 of the Note Purchase Agreement.


5.                             Amendment.  Amendments and modifications of this Note may
be made only in the manner provided in Section 12.5 of the Note Purchase
Agreement.


6.                             Security.  This Note shall at all times be secured by
certain collateral, pursuant to the terms of the Collateral Documents.  This Note and the obligations hereunder are
senior secured obligations of the Company and rank senior to all funded
indebtedness of the Company.


7.                             Use
of Proceeds.  The Company shall use
the principal amount of this Note in accordance with the permitted uses
described in Section 7.4 of the Note Purchase Agreement.


8.                             Suits
for Enforcement.  Subject to the provisions
of Article IX of the Note Purchase Agreement, upon the occurrence of any one or
more Events of Default, the Holder of this Note may proceed to protect and
enforce its rights hereunder by suit in equity, action at law or by other
appropriate proceeding, whether for the specific performance of any covenant or
agreement contained in the Note Purchase Agreement or this Note or in aid of
the exercise of any power granted in the Note Purchase Agreement or this Note,
or may proceed to enforce the payment of this Note, or to enforce any other
legal or equitable right of the Holders of this Note.


9.                             Remedies
Cumulative.  No remedy herein
conferred upon the Holders is intended to be exclusive of any other remedy and
each and every such remedy shall be cumulative and shall be in addition to
every other remedy given hereunder or now or hereafter existing at law or in
equity or by statute or otherwise.



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10.                           Remedies
Not Waived.  No course of dealing
between the Company and the Holders or any delay on the part of the Holders in
exercising any rights hereunder shall operate as a waiver of any right.


11.                           Transfer.


(a)  The term “Holders”
as used herein shall also include any transferee of this Note whose name has
been recorded or is required to be recorded by the Company in the Note Register
(as defined below). Each transferee of this Note acknowledges that this Note
has not been registered under the Securities Act, and may be transferred only
pursuant to an effective registration under the Securities Act or pursuant to
an applicable exemption from the registration requirements of the Securities
Act and in accordance with the procedures provided in the Note Purchase
Agreement.


(b)  The Company shall
maintain a register (the “Note Register”) in its principal office for the
purpose of registering the Note and any transfer or partial transfer thereof,
which register shall reflect and identify, at all times, the ownership of
record of any interest in the Note. Upon the issuance of this Note, the Company
shall record the name and address of the initial purchasers of this Note in the
Note Register as the first Holders.  Upon
surrender for registration of transfer or exchange of this Note at the
principal offices of the Company, the Company shall, at its expense, execute
and deliver one or more new Notes of like tenor in accordance with and subject
to the procedures for transfer and exchange set forth in the Note Purchase
Agreement.


(c)  Subject to
Sections 11(a) and 11(b) hereof and the limitations contained in Section 12 of
the Note Purchase Agreement, this Note may be transferred or assigned, in whole
or in part, by the Holders only with the prior written consent of the Company,
which shall not be unreasonably withheld.


12.                           Replacement
of Note.  On receipt by the Company of
an affidavit of an authorized representative of the Holders stating the
circumstances of the loss, theft, destruction or mutilation of this Note (and
in the case of any such mutilation, on surrender and cancellation of such
Note), the Company, at the Holders’ expense, will promptly execute and deliver,
in lieu thereof, a new Note of like tenor.  If required by the Company, such Holders must
provide indemnity sufficient in the reasonable judgment of the Company to
protect the Company from any loss which the Company may suffer if a lost,
stolen or destroyed Note is replaced.


13.                           Covenants
Bind Successors and Assigns.  All the
covenants, stipulations, promises and agreements in this Note contained by or
on behalf of the Company shall bind its successors and assigns, whether so
expressed or not.  Each Holder shall be
deemed to have made in favor of the Company the representations and warranties
set forth in Article VI of the Note Purchase Agreement as of the date such
Holder acquires this Note for value.


14.                           Notices.  All notices, demands and other communications
provided for or permitted hereunder shall be made in writing and shall be by
registered or certified first-class mail, return receipt requested, telecopier
(with receipt confirmed), courier service or personal delivery at the addresses
and in the manner specified in Section 12.3 of the Note



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Purchase Agreement. All such notices and
communications shall be deemed to have been duly given: if personally
delivered, when delivered by hand; if delivered by commercial overnight courier
service, when delivered by courier; if mailed, five (5) Business Days after
being deposited in the mail, postage prepaid; or if telecopied, when receipt is
acknowledged.


15.                           GOVERNING
LAW. THIS NOTE SHALL BE GOVERNED BY, CONSTRUED IN ACCORDANCE WITH, AND
ENFORCED UNDER, THE LAWS OF THE STATE OF NEW YORK, WITHOUT REGARD TO THE
PRINCIPLES OF CONFLICTS OF LAW OF SUCH STATE (INCLUDING GIVING EFFECT TO
GENERAL OBLIGATIONS LAW SECTION 5-1401).


16.                           JURISDICTION,
JURY TRIAL WAIVER, ETC.


(a)  EACH PARTY TO
THIS NOTE HEREBY IRREVOCABLY AGREES THAT ANY LEGAL ACTION OR PROCEEDING ARISING
OUT OF OR RELATING TO THIS NOTE OR ANY AGREEMENTS OR TRANSACTIONS CONTEMPLATED
HEREBY OR THEREBY MAY BE BROUGHT IN THE COURTS OF THE STATE OF NEW YORK OR OF
THE UNITED STATES OF AMERICA FOR THE SOUTHERN DISTRICT OF NEW YORK AND HEREBY
EXPRESSLY SUBMITS TO THE PERSONAL JURISDICTION AND VENUE OF SUCH COURTS FOR THE
PURPOSES THEREOF AND EXPRESSLY WAIVES ANY CLAIM OF IMPROPER VENUE AND ANY CLAIM
THAT SUCH COURTS ARE AN INCONVENIENT FORUM. 
EACH PARTY HEREBY IRREVOCABLY CONSENTS TO THE SERVICE OF PROCESS OF ANY
OF THE AFOREMENTIONED COURTS IN ANY SUCH SUIT, ACTION OR PROCEEDING BY THE
MAILING OF COPIES THEREOF BY REGISTERED OR CERTIFIED MAIL, POSTAGE PREPAID, TO
ITS ADDRESS SET FORTH IN SECTION 13.2 OF THE NOTE PURCHASE AGREEMENT, SUCH
SERVICE TO BECOME EFFECTIVE TEN (10) DAYS AFTER SUCH MAILING.


(b)  EACH PARTY TO
THIS NOTE HEREBY WAIVES ITS RIGHT TO A JURY TRIAL WITH RESPECT TO ANY ACTION OR
CLAIM ARISING OUT OF ANY DISPUTE IN CONNECTION WITH THIS NOTE OR ANY OF THE
OTHER INVESTMENT DOCUMENTS, ANY RIGHTS OR OBLIGATIONS HEREUNDER OR THEREUNDER
OR THE PERFORMANCE OF SUCH RIGHTS AND OBLIGATIONS.  THE COMPANY (I) CERTIFIES THAT NEITHER THE HOLDERS
NOR ANY REPRESENTATIVE, AGENT OR ATTORNEY OF THE HOLDERS HAS REPRESENTED,
EXPRESSLY OR OTHERWISE, THAT THE HOLDERS WOULD NOT, IN THE EVENT OF LITIGATION,
SEEK TO ENFORCE THE FOREGOING WAIVERS AND (II) ACKNOWLEDGES THAT THE HOLDERS HAVE
BEEN INDUCED TO PURCHASE THIS NOTE BY, AMONG OTHER THINGS, THE WAIVERS AND
CERTIFICATIONS CONTAINED HEREIN.


17.                           Severability.  If any one or more of the provisions
contained herein, or the application thereof in any circumstance, is held
invalid, illegal or unenforceable in any respect for any reason, the validity,
legality and enforceability of any such provision in every other respect and of
the remaining provisions hereof shall not be in any way impaired, unless the
provisions held invalid, illegal or unenforceable shall substantially impair
the benefits of the



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remaining
provisions hereof. The Company and the Holders further agree to replace such
invalid, illegal or unenforceable provision of this Note with a valid, legal
and enforceable provision that will achieve, to the extent possible, the
economic, business and other purposes of such invalid, illegal or unenforceable
provision.


18.                           Headings.  The headings in this Note are for convenience
of reference only and shall not limit or otherwise affect the meaning hereof.



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IN WITNESS WHEREOF, the undersigned has executed this
Note as of the date first written above.


	
  

  	
  FERMAVIR PHARMACEUTICALS, INC.

  
	
   

  	
   

  
	
   

  	
   

  
	
   

  	
  By:

  	
   

  	
   

  
	
   

  	
   

  	
       Name:

  	
   

  
	
   

  	
   

  	
       Title:

  	
   

  



 



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