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                                                                    Exhibit 10.5

                                     WARRANT

THE SECURITIES REPRESENTED BY THIS CERTIFICATE (THE "SECURITIES") HAVE BEEN
ISSUED AND SOLD IN RELIANCE UPON EXEMPTIONS FROM REGISTRATION UNDER THE
SECURITIES ACT OF 1933 (THE "1933 ACT"), AND APPROPRIATE EXEMPTIONS FROM
REGISTRATION UNDER THE SECURITIES LAWS OF OTHER APPLICABLE JURISDICTIONS. THE
SECURITIES MAY NOT BE OFFERED FOR SALE, SOLD OR TRANSFERRED OTHER THAN PURSUANT
OT AN EFFECTIVE REGISTRATION OR AN EXEMPTION SATISFACTORY TO THE ISSUER OF
COMPLIANCE WITH THE 1933 ACT AND THE APPLICABLE SECURITIES LAW OF ANY OTHER
JURISDICTION. THE ISSUER SHALL BE ENTITLED TO REQUIRE AN OPINION OF COUNSEL
REASONABLY SATISFACTORY TO IT WITH RESPECT TO COMPLIANCE WITH THE 1933 ACT.

NO.: __                                                        Right to Purchase
                                                             Preferred Shares of
                                                                 Inhibitex, Inc.

                                 INHIBITEX, INC.

                              Amended and Restated
                        Preferred Shares Purchase Warrant
                                  (Bridge Loan)

         Inhibitex, Inc., a Delaware corporation (the "Company"), hereby
certifies that, for value received, ____________________________ (the "Holder"),
or its successors or registered assigns, is entitled, subject to the terms set
forth below, to purchase form the Company, commencing on the Exercise Date (as
hereinafter defined) and thereafter, at any time or from time to time before
5:00 p.m., Atlanta, Georgia time, on the Expiration Date (as hereinafter
defined), that number of fully paid and nonassessable Preferred Shares (as
hereinafter defined) as is equal to the Warrant Number (as hereinafter defined),
at a purchase price per share as is equal to the Purchase Price (as hereinafter
defined). The number of such Preferred Shares and the Purchase Price are subject
to adjustment as provided in this Warrant.

         This Warrant is issued pursuant to that certain Loan Agreement dated as
of March 31, 1999, as amended by that certain Amended and Restated Loan
Agreement (the "Loan Agreement"), dated as of March 31, 2000, by and among the
Company and the lenders named therein, a copy of which is on file at the
principal office of the Company (the "Original Warrant"). This Warrant is one of
several warrants (the "Purchaser Warrants") representing the right to purchase
Preferred Shares issuable pursuant to and contemplated by the Loan Agreement and
replaces in its entirety the Original Warrant.

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         As used herein the following terms, unless the context otherwise
requires, have the respective meanings set forth below:

         (a)      The term "Company" shall include Inhibitex, Inc., a Delaware
corporation, and any corporation that shall succeed to or assume the obligations
of Inhibitex, Inc. hereunder.

         (b)      The term "Preferred Shares" means the Company's Series B
Convertible Preferred Stock, and any other securities into which or for which
any of the securities may be converted or exchanged pursuant to a plan of
recapitalization, reorganization, merger, sale of assets or otherwise.

         (c)      The term "Purchase Price" shall mean, subject to adjustment
pursuant to Section 5 hereof, $1.50 a share.

         (d)      The term "Outstanding Principal Amount" shall mean the maximum
aggregate principal amount then outstanding of one or more Notes (the "Notes")
from the Company to the Holder and the other holder of the Notes and issued
pursuant to the Loan Agreement.

         (e)      The Term "Warrant Number" shall mean that number of the
Company's Preferred Shares equal to the quotient of fifteen percent of the
amount loaned to the Company by Holder divided by the applicable Purchase Price.

         1.       Term. This Warrant is exercisable, in whole or in part, at any
time and from time to time commencing on the earlier of (i) the consolidation or
merger of the Company or a sale of all or substantially all of the capital
shares or assets of the Company, or (ii) December 31, 1999 (such date referred
to as the "Exercise Date") and prior to the Expiration Date (as hereinafter
defined). This Warrant shall expire and be of no further force and effect upon
the earlier to occur of (x) the time when it has been exercised with respect to
all Preferred Shares which the Holder is or may become entitled to purchase
hereunder or (y) 5:00 p.m., Atlanta, Georgia time on January 1, 2005 (the
"Expiration Date").

         2.       Exercise of Warrant. The purchase rights represented by this
Warrant may be exercised by the Holder as provided in Section 1 in whole or in
part by the surrender of this Warrant to the Company at its principal office in
Alpharetta, Georgia, along with a written notice stating that the Holder intends
to purchase all or a specified number of Preferred Shares pursuant to this
Warrant and specifying the name or names in which the Holder wishes the
certificate or certificates for the Preferred Shares to be issued, and together
with payment of the Purchase Price for the shares then purchased. Such payment
shall be made, at the option of the Holder, by certified or official bank check
payable to the order of the Company in same day funds or by wire transfer of
same day funds to an account designated by the Company for such purpose. At the
option of the Holder, the Holder may, as payment of the Purchase Price for the
Preferred Shares then purchased, elect to receive a number of Preferred Shares
equal to the number of Preferred Shares then purchased, less a number of
Preferred Shares then having a fair market value equal to the Purchase Price of
the Preferred Shares then purchased or may elect to deliver

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shares of the Company's Common stock acquired upon any conversion of shares of
the Company's preferred stock having a fair market value equal to the Purchase
Price of the Preferred Shares then purchased. If the number of Preferred Shares
then purchased is less than the total number of Preferred Shares then issuable
upon exercise of this Warrant, the Company shall cancel this Warrant upon
surrender and shall execute and deliver a new Warrant of like tenor and date for
the balance of the shares issuable upon the exercise of this Warrant (provided,
that if only a fractional share remains unexercised, the Company shall make a
cash payment therefor in lieu of issuing a new Warrant). As promptly as
practicable after such surrender of this Warrant, the Company shall issue and
deliver to the Holder, at the address appearing in the books of the Company or
otherwise designated by Holder, a certificate or certificates for the applicable
number of Preferred Shares. Certificates representing Preferred Shares purchased
pursuant to this Warrant shall bear restrictive legends substantially similar to
those at the head of this Warrant and as required by the Loan Agreement, or such
other restrictive legends as the Company and the Company's counsel deem
necessary or advisable under applicable law.

         3.       Reservation of Shares; Validity of Issuance. The Company
covenants and agrees that it shall reserve for issuance as of the Exercise Date
of this Warrant and keep available out of its authorized but unissued Preferred
Shares, free from preemptive rights, such number of Preferred Shares for which
this Warrant shall from time to time be exercisable. The Company represents and
warrants that all shares issued upon the exercise of this Warrant will, upon
issuance, be fully paid and nonassessable and be free form all taxes, liens and
charges in respect of their issuance.

         4.       Merger, Consolidation or Sale of Assets. In the event of any
capital reorganization or any consolidation or merger of the Company with or
into another person (each, a "Reorganization"), the Holder shall have the right
to purchase and receive, upon the basis and upon the terms and conditions
specified in this Warrant and in lieu of the Preferred Shares of the Company
then purchasable and receivable upon the exercise of the rights represented by
this Warrant, the kind and number of shares of stock, securities or other
property (including cash) of the Company, or other corporation resulting from
such consolidation or surviving such merger, to which the holder of the number
of outstanding Preferred Shares equal to the number of shares of such stock then
purchasable and receivable upon the exercise of the rights represented by this
Warrant immediately prior to such Reorganization would have been entitled to
receive with application of the provisions herein set forth with respect to the
rights and interests thereafter of the Holder to the end that the provisions
herein set forth shall thereafter be applicable, as nearly as reasonably may be,
in relation to any shares, other securities or property thereafter deliverable
upon the exercise of this Warrant. The Company shall not effect any
Reorganization unless prior to or simultaneously with the consummation of such
Reorganization the successor corporation (if other than the Company) resulting
from such Reorganization shall assume by written instrument executed and
delivered to the Holder at the address of the Holder appearing in the books of
the Company, the obligation to deliver to the Holder such shares, securities or
property as, in accordance with the provisions of this Section 4, the Holder may
be entitled to purchase. The provisions of this Section 4 shall similarly apply
to successive Reorganizations.

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         5.       Adjustments for Stock Splits and Combinations. If outstanding
Preferred Shares shall be subdivided into a greater number of shares, or a
dividend in Preferred Shares or other securities of the Corporation convertible
or exchangeable into Preferred Shares (in which latter event the number of
Preferred Shares issuable upon the conversion or exchange of such securities
shall be deemed to have been distributed), shall be paid in respect to the
Preferred Shares, the number of Preferred Shares which may be acquired by the
Holder upon the exercise of this Warrant shall, simultaneously with the
effectiveness of such subdivision or immediately after the record date of such
dividend, be proportionately increased, and conversely, if the outstanding
Preferred Shares shall be combined into s smaller number of shares, the number
of Preferred Shares which may be acquired by the Holder upon the exercise of
this Warrant shall, simultaneously with the effectiveness of such combination,
be proportionately reduced.

         6.       Notice of Certain Events. If at any time:

                  (i)      the Company shall declare or pay and dividend or make
any distribution to the holders of its Preferred Shares:

                  (ii)     the Company shall offer for subscription pro rata to
the holders of its Preferred Shares any additional shares of stock of any class
or other rights;

                  (iii)    there shall be any capital reorganization or
reclassification of the capital stock of the Company or consolidation or merger
of the Company with, or sale of all or substantially all of its assets to,
another corporation or entity; or

                  (iv)     there shall be a voluntary or involuntary
dissolution, liquidation or winding up of the Company.

then, in any one or more of the above cases, the Company shall given written
notice, by first class mail, postage prepaid, or overnight delivery, addressed
to the Holder at the address of the Holder as shown on the books of the Company,
of the date on which (i) the books of the Company shall close or a record shall
be taken for such dividend, distribution or subscription rights or (ii) such
reorganization, reclassification, consolidation, merger, sale, dissolution,
liquidation or winding up shall take place, as the case may be. Such notice
shall also specify the date as of which the holders of Preferred Shares of
record shall participate in said dividend, distribution or subscription rights,
or shall be entitled to exchange their Preferred Shares for securities or other
property deliverable upon such reorganization, reclassification, consolidation,
merger, sale, dissolution, liquidation or winding up, as the case may be. Such
written notice shall be given not less than 30 days prior to the record date or
the date on which the transfer books of the Company are closed in respect to
such record date or prior to the action in question. Any notices given pursuant
to this Section 6 shall be effective and deemed received upon the date of actual
receipt or upon the fifth calendar day subsequent to deposit in the United
States mail (or other comparable mail system), whichever is earlier.

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         7.       No Impairment. The Company will not, by amendment of its
Amended and Restated Certificate of Incorporation or through any reorganization,
transfer of assets, consolidation, merger, dissolution, issue or dale of
securities or any other voluntary action, avoid or seek to avoid the observance
or performance of any of the terms to be observed or performed by the Company
under this Warrant, but will at all times in good faith assist in the carrying
out of all the provisions of Sections 3 through 6 and in the taking of all such
action as may be necessary or appropriate in order to protect the rights of the
Holder.

         8.       No Voting Rights. This Warrant shall not entitle the Holder to
any voting rights or other rights as a shareholder of the Company, and no
dividend or interest shall be payable or accrue in respect of this Warrant or
the interest represented by or the shares purchasable under this Warrant until
and unless, and except to the extent that, this Warrant shall be exercised.

         9.       Stock Certificates. The issuance of stock certificates upon
the exercise of this Warrant shall be made without charge to the Holder for any
tax (other than taxes attributable to any difference between the fair market
value and the exercise price of this Warrant on the date of the exercise of this
Warrant or transfer taxes resulting from issuance of stock certificates to a
person other than the Holder) in respect of the issuance of such stock. The
Holder shall for all purpose be deemed to have become the holder of record of
the shares issued upon exercise of this Warrant on the date on which the Warrant
was surrendered and payment of the Warrant Price was made, irrespective of the
date of delivery of the certificate for such shares, except that, if the date of
such surrender and payment is a date when the stock transfer books of the
Company are closed, the Holder shall be deemed to have become the holder of such
shares at the close of business on the next succeeding date on which the stock
transfer books are open.

         10.      Lost, Stolen, Mutilated or Destroyed Warrant. Upon receipt of
evidence reasonably satisfactory to the Company of the loss, theft, mutilation
or destruction of this Warrant, and in case of loss, theft or destruction, upon
the agreement of the Holder to indemnify the Company, or in the case of
mutilation, upon surrender and cancellation of this Warrant, the Company shall
issue a new Warrant of like denomination and tenor as the Warrant so lost,
stolen, mutilated or destroyed.

         11.      Applicable Law. This Warrant shall be governed by and
construed in accordance with the internal laws of the State of Georgia, without
regard to its principles of conflicts of laws.

         IN WITNESS WEREOF, the Company's duly authorized officer has executed
this Warrant to be effective as of the ___ day of _______, _____.

                                           INHIBITEX, INC.

                                           By: ___________________
                                           William D. Johnston
                                           President and Chief Executive Officer

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