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                                                                   Exhibit 10.13

                         EXECUTIVE EMPLOYMENT AGREEMENT

         THIS AGREEMENT, dated as of FEBRUARY 20, 2004 is between Inhibitex,
Inc., a Delaware corporation (the "Company"), and WILLIAM D. JOHNSTON, PH.D.
(the "Executive").

         WHEREAS, the Company desires to assure itself of the Executive's
employment in an executive capacity and to compensate him for such employment;
and

         WHEREAS, the Executive is willing to be employed by the Company upon
the terms and subject to the conditions contained in this Agreement.

         NOW THEREFORE, in consideration of the premises and mutual covenants
contained herein and for other good and valuable consideration, the adequacy and
receipt of which are hereby acknowledged, the parties agree as follows:

Section 1. Position, Duties and Responsibilities.

                  (a)      During the Term (as defined in Section 2), the
Executive shall serve as the CHIEF EXECUTIVE OFFICER & PRESIDENT of the Company
consistent with the by-laws of the Company, and shall be responsible for the
duties identified in the attached Appendix I, such other duties as are attendant
to such offices and such other managerial duties and responsibilities with the
Company, its affiliates, subsidiaries or divisions consistent with such position
as may be assigned by the Board of Directors of the Company (the "Board"). The
Executive shall devote his full energies, interest, abilities and productive
time to the business and affairs of the Company and to promoting its best
interests. The Executive acknowledges and agrees that although his duties shall
be performed from the Company's offices in the Atlanta, Georgia metropolitan
area or at such other places as shall be necessary according to the needs,
business and opportunities of the Company, the performance by the Executive of
his duties hereunder may require substantial travel from time to time by the
Executive. The Executive further agrees that, during the Term, the Company shall
be the Executive's sole employer.

                  (b)      Executive understands that the provisions of any
employee handbooks, personnel manuals and any and all other written statements
of or regarding personnel policies, practices or procedures that are or may be
issued by the Company (the "Company Policies") do not and shall not constitute a
contract of employment and do not and shall not create any vested rights; and
that any such provisions may be changed, revised, modified, suspended, canceled,
or eliminated by the Company at any time, in its sole discretion, with or
without notice.

                  (c)      Executive shall comply with all applicable Company
Policies, which may be in effect from time to time during the Term. Copies of
all such Company Policies may be examined in the Human Resource Department for
the Company. If a provision in any policy conflicts with this Agreement, the
terms of this Agreement shall prevail.

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                  (d)      For up to a one (1) year period following any
termination of the Executive's employment, upon the request of the Company, the
Executive shall reasonably cooperate with the Company in all matters relating to
the winding up of pending work on behalf of the Company and the orderly transfer
of work to other employees of the Company. The Executive shall also cooperate in
the defense of any action brought by any third party against the Company that
relates in any way to the Executive's acts or omissions while employed by the
Company. The Company shall reimburse the Executive for his reasonable
out-of-pocket costs incurred in connection with such cooperation.

Section 2. Term of Employment.

         The initial term (the "Initial Term") of this Agreement shall commence
on FEBRUARY 20, 2004 and continue through FEBRUARY 20, 2005 (the "Initial
Expiration Date"). On each anniversary of the Initial Expiration Date, this
Agreement will be renewed automatically for an additional one (1) year period
(the "Extended Term") (without any action by either party) on the last day of
the Initial Term and on each anniversary thereof, unless the Executive's
employment under this Agreement is earlier terminated in accordance with Section
4. Executive may elect not to renew his or her employment under this Agreement
for any reason upon sixty (60) days written notice. For purposes of this
Agreement, "Term" means the Initial Term and, as extended, the Extended Term.

Section 3. Compensation; Benefits; Expenses.

                  (a)      Base Salary. For all services rendered by the
Executive hereunder during the Term, the Company shall pay the Executive an
annual salary equal to THREE HUNDRED TWENTY-SEVEN THOUSAND SEVEN HUNDRED dollars
($327,700), less standard deductions and withholdings, payable in equal
installments at the times and pursuant to the procedures regularly established
for the payment of salaries generally to employees, and as they may be amended
by the Company during the Term. The Executive's salary will be reviewed from
time to time by the Board, a committee of the Board, or otherwise in accordance
with the Company's established procedures for adjusting salaries, and be subject
to increases (but not decrease, except pursuant to an across-the-board salary
reduction as described in Section 4(a)(iv)(B)) pursuant to such procedures.

                  (b)      Incentive Compensation. The Executive shall be
eligible to participate in such bonus and incentive (including stock option and
other equity-based) compensation plans of the Company, if any, in which other
executives of the Company are generally eligible to participate, as the Board or
a Committee thereof shall determine from time to time in its sole discretion,
subject to and in accordance with the terms and provisions of such plans.
Subject to the terms and conditions of such bonus and incentive compensation
plans, the Executive shall be eligible for annual cash incentive compensation of
up to 50% of the then annual gross salary.

                  (c)      Benefits. The Company shall provide the Executive
with the right to participate in and to receive benefits from the medical plan
and all similar benefits

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made generally available to similarly situated executives of the Company. The
amount and extent of benefits to which the Executive is entitled shall be
governed by the specific benefit plan or plans, as such may be amended from time
to time.

                  (d)      Stock Options. The Executive has heretofore been
granted employee stock options under the Inhibitex, Inc. Amended and Restated
1998 Equity Ownership Plan and/or the 2002 Inhibitex, Inc. Stock Incentive Plan
to purchase shares of the Company's common stock, par value $0.001 per share, on
the terms set forth in a the related stock option agreement(s) entered into by
the Executive and the Company. Any stock option granted to the Executive
subsequent to December 31, 2003 shall provide that upon the Executive's
Retirement, the vested portion of such stock option may be exercised at any time
prior to the earlier of the expiration date of such option and 24 months after
the date of the Executive's Retirement. "Retirement" shall mean the cessation of
employment with the Company after the Executive has attained age fifty-nine and
one-half (59-1/2) and completed five (5) or more consecutive years of service
with the Company or any subsidiary.

                  (e)      Reimbursement of Expenses. It is contemplated that in
connection with the Executive's Employment hereunder, he may be required to
incur business, entertainment and travel expenses. The Company agrees to
promptly reimburse the Executive in full for all reasonable out-of-pocket
business, entertainment and other related expenses (including all reasonable
expenses of travel and living expenses while away from home on business or at
the request of, and in service of, the Company) incurred or expended by him
incident to the performance of his duties hereunder, provided that the Executive
properly account for such expenses in accordance with the policies and
procedures established by the Board and applicable to the executives of the
Company.

                  (f)      Vacation; Personal Days. During the Term, the
Executive shall be entitled to no less than four (4) weeks vacation with pay
during each calendar year of his employment hereunder provided that the vacation
days taken do not materially interfere with the operations of the Company. Such
vacation may be taken, in the Executive's discretion, at such time or times as
are not inconsistent with the reasonable business needs of the Company. The
Executive shall also be entitled to all paid holidays and personal days given by
the Company to its executives. Vacation, holiday and personal days shall
additionally be subject to applicable Company Policies.

Section 4. Termination.

                  (a)      The Executive's employment under this Agreement may
be terminated under the following circumstances:

                           (i)      Death. The Executive's employment shall
         immediately terminate upon his death.

                           (ii)     Disability. In the event the Executive shall
         be unable to render the services or perform his duties hereunder by
         reason of "Disability," as

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         such term is defined in the Company's Long-Term Disability Plan, as the
         same shall be amended from time to time; the Company shall have the
         right to terminate this Agreement immediately upon notice to the
         Executive.

                           (iii)    Termination of Employment by the Company for
         Cause. The Company may terminate the employment of the Executive
         immediately for Cause (as hereinafter defined). The term "Cause," as
         used herein, shall mean (1) the Executive's willful misconduct, gross
         negligence, dishonesty or fraud in the performance of his duties
         hereunder, (2) the material breach of this Agreement by the Executive
         after notice of such breach and a reasonable opportunity to cure, (3)
         the Executive's willful refusal or failure to perform his duties
         hereunder or under any lawful directive of the Board or the Chairman of
         the Board, as the case may be, which is consistent with his title and
         position after notice of such failure and a reasonable opportunity to
         cure, or (4) the conviction, plea of guilty or nolo contendere of the
         Executive in respect of any felony or other crime involving moral
         turpitude, dishonesty, theft or unethical business conduct.

         (iv) Termination of Employment by Executive for Good Reason. The
         Executive may resign and terminate his employment hereunder for Good
         Reason (as defined below) by providing a written notice thereof within
         sixty (60) days from the occurrence of the event that the Executive is
         deeming Good Reason. For purposes of this Agreement, "Good Reason"
         shall mean there has occurred, without the express written consent of
         the Executive:

                           (A) the assignment to the Executive of any duties
                           materially inconsistent with his status as the Chief
                           Executive Officer of the Company or a substantial
                           diminution in the nature or status of his
                           responsibilities;

                           (B) a reduction by the Company in the Executive's
                           Base Salary as in effect on the date hereof or as the
                           same may be increased from time to time except for
                           across-the-board salary reductions similarly
                           affecting all executives of the Company;

                           (C) (1) the relocation of the Company's principal
                           executive offices to a location outside the Atlanta,
                           Georgia metropolitan area or (2) the Company's
                           requiring the Executive to perform his duties
                           anywhere other than the Company's principal executive
                           offices; provided that required travel on the
                           Company's business to an extent substantially
                           consistent with the Executive's responsibilities
                           shall not constitute "Good Reason";

                           (D) the failure by the Company to continue in effect
                           without any material adverse change any compensation
                           plan in which the Executive was participating or the
                           failure by the Company to continue the Executive's
                           participation therein, unless an equitable

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                           arrangement (embodied in an ongoing substitute or
                           alternative plan) has been made with respect to such
                           plan or participation;

                           (E) the failure by the Company to continue to provide
                           the Executive with benefits substantially similar to
                           those enjoyed by the Executive under the Company's
                           employee stock ownership, life insurance, medical,
                           health-and-accident, or disability plans in which the
                           Executive was participating, the taking of any action
                           by the Company which would directly or indirectly
                           materially reduce any of such benefits or deprive the
                           Executive of any other material fringe benefits
                           enjoyed by the Executive, or the failure by the
                           Company to provide the Executive with the number of
                           paid vacation days to which the Executive is entitled
                           on the basis of years of service with the Company in
                           accordance with the Company's normal vacation policy,
                           except for across-the-board changes in such benefits
                           similarly affecting all executives of the Company; or

                           (F) the failure of the Company to obtain a
                           satisfactory agreement from any successor to assume
                           and agree to perform this Agreement, as contemplated
                           in Section 16 hereof.

         (v) Terminations other than for Cause, Good Reason, Disability or upon
         Death. In addition to the foregoing, either party may terminate this
         Agreement at any time, by providing thirty (30) days prior written
         notice of his or its desire to terminate.

                  (b)      Notice of Termination. Any termination of the
Executive's employment by the Company or by the Executive (other than a
termination pursuant to Section 4(a)(i) above) shall be communicated by written
notice of termination to the other party.

                  (c)      Date of Termination. "Date of Termination" shall mean
(i) if the Executive's employment is terminated by his death, the date of his
death or (ii) in all other circumstances, the date specified in the notice of
termination.

Section 5. Compensation Upon Termination.

                  (a)      Compensation Upon Termination Upon Death. In the
event of the death of the Executive during the Term, the Executive's designated
beneficiary, or, in the absence of such designation, the estate or other legal
representative of the Executive (collectively, the "Estate") shall be paid,
within thirty (30) days of the Executive's death, an amount equal to the sum of
the Executive's unpaid salary and any earned but unpaid bonuses through the Date
of Termination. The Estate shall be entitled to other death benefits in
accordance with the terms of the Company's benefit programs and plans.

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                  (b)      Compensation Upon Termination for Disability. If the
Executive's employment hereunder is terminated for Disability, the Executive
shall be entitled to receive (if entitled thereto) disability compensation and
benefits in accordance with the Company's benefit programs and plans.

                  (c)      Compensation Upon Termination for Cause. If the
Executive's employment is terminated by the Company for Cause, the Company shall
pay the Executive his salary through the Date of Termination and the Company
shall have no further obligations to the Executive under this Agreement.

                  (d)      Compensation Upon Termination Upon a Change in
Control (other than for Cause, Disability or upon Death).

                           (i)      If the Executive's employment is terminated
         by the Executive for Good Reason or by the Company within one (1) year
         after the consummation of a Change in Control (as hereafter defined)
         (or in contemplation of a Change of Control that is reasonably likely
         to occur) for any reason other than pursuant to Section 4(a)(i),
         4(a)(ii) or 4(a)(iii) hereof, the Company, within sixty (60) days of
         the Date of Termination, shall pay to the Executive (or in the event of
         the Executive's death, the Executive's estate) a lump-sum cash amount
         equal to the sum of (x) the Executive's unpaid salary through the Date
         of Termination; plus (y) any bonus compensation earned and unpaid
         through the Date of Termination; provided, however, that any bonus
         compensation conditioned upon the satisfaction of performance goals
         shall not be paid unless such performance goals are actually satisfied;
         plus (z) the product of (A) a fraction the numerator of which is the
         number of months in the Change in Control Severance Period (as
         hereafter defined) and the denominator of which is 12 and (B) the sum
         of (1) Executive's annual base salary as then in effect and (2) the
         bonus or incentive compensation paid to the Executive in respect of the
         most recent fiscal year prior to the year in which the Change in
         Control occurs. In addition, the Executive shall continue to be covered
         under the Company's group health, life and disability insurance for the
         Change in Control Severance Period or, in the Company's sole
         discretion, the Executive shall be provided comparable coverage or the
         economic equivalent thereof. The "Change in Control Severance Period"
         shall be twenty-four (24) months.

                           (ii)     Notwithstanding any other provision herein
         to the contrary, in the event that the Executive becomes entitled to
         any payments under Section 5(d)(i) ("Termination Payments") and any
         portion of such Termination Payments, when combined with any other
         payments or benefits provided to the Executive (including, without
         limiting the generality of the foregoing, by reason of any stock
         options), in the absence of this Section 5(d)(ii), would be subject to
         the tax (the "Excise Tax") imposed by Section 4999 of the Internal
         Revenue Code of 1986, as amended (the "Code"), then (subject to Section
         5(d)(iii) hereof) the amount payable to the Executive under Section
         5(d)(i) shall be reduced such that none of the amounts payable to the
         Executive under Section 5(d)(i) and any other payments or benefits
         received or to be received by the

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         Executive in connection with a Change in Control or the termination of
         the Executive's employment (whether pursuant to the terms of this
         Agreement or any other plan, arrangement or agreement with the Company,
         any person whose actions result in a Change in Control or any person
         having such a relationship with the Company or such person as to
         require attribution of stock ownership between the parties under
         Section 318(a) of the Code) shall be treated as "parachute payments"
         within the meaning of Section 280G(b)(2) of the Code. For purposes of
         applying the foregoing sentence, if in the opinion of tax counsel
         selected by the Company's independent auditors prior to the Change in
         Control and reasonably acceptable to the Executive, such payments or
         benefits (in whole or in part) represent reasonable compensation for
         services actually rendered within the meaning of Section 280G(b)(4) of
         the Code, then such amounts shall be excluded from any such
         calculation. Furthermore, in determining the maximum amount of the
         payments to the Executive which would not constitute a parachute
         payment within the meaning of Sections 280G(b)(1) and (4), the value of
         any non-cash benefits or any deferred payment or benefit shall be
         determined by the Company's independent auditors in accordance with the
         principles of Sections 280G(d)(3) and (4) of the Code or any applicable
         proposed or final Treasury Regulations promulgated under the Code.

                           (iii)    If the net after-tax amount of the
         Termination Payments which would be payable to the Executive in the
         absence of the reduction described in Section 5(d)(ii) above exceeds
         the net after-tax amount of the Termination Payments which would be
         payable to the Executive if the reduction described in Section 5(d)(ii)
         above were applicable, then the reduction to the Executive's
         Termination Payments described in Section 5(d)(ii) above shall not be
         applicable. For purposes of computing such net after-tax amounts, the
         Termination Payments shall be treated as subject to Federal income tax
         and any state and local income taxes (based upon the residence of the
         Executive at the time the first amount of Termination Payments is to be
         paid hereunder) at the highest marginal rate of income tax imposed upon
         individuals (but without assuming any reduction in Federal income taxes
         that could be obtained from the deduction of any such state or local
         taxes if paid in such year), shall be subject only to the Medicare
         portion of the F.I.C.A tax and, in calculating the net after-tax amount
         of the Termination Payments which would otherwise be payable to the
         Executive if the reduction described in Section 5(d)(ii) above were not
         applicable, any applicable Excise Tax, and all such taxes shall be
         computed based upon the tax rates in effect for the calendar year in
         which the first amount of Termination Payments are to be paid
         hereunder. The determination of the net after-tax amounts will be made
         by the Company's independent auditors prior to the Change in Control,
         whose determination will be binding on both the Executive and the
         Company.

For purposes of this Agreement, a "Change in Control" of the Company shall mean
(A) a change in control of a nature that would be required to be reported in
response to Item 6(e) of Schedule 14A of Regulation 14A promulgated under the
Securities Exchange Act of 1934, as amended (the "Exchange Act"), whether or not
the Company is then subject

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to such reporting requirement; (B) any "person" (as such term is used in
Sections 13(d) and 14(d) of the Exchange Act) other than the Company or an
employee benefit plan maintained by the Company, is or becomes the "beneficial
owner" (as defined in Rule 13d-3 under the Exchange Act), directly or
indirectly, of securities of the Company representing 50% or more (the
"Requisite Percentage") of the combined voting power of the Company's then
outstanding securities (provided that if the Company is not subject to the
reporting requirements under Section 13(a) or 15(d) of the Exchange Act, the
acquisition by a "person" of the Requisite Percentage in one or more
institutional private equity securities offerings shall not constitute a Change
in Control), or (C) during any period of two (2) consecutive years, individuals
who at the beginning of such period constitute the Board, including for this
purpose any new director whose election or nomination for election by the
Company's stockholders was approved by a vote of at least two-thirds of the
directors then still in office who were directors at the beginning of the
period, cease for any reason to constitute a majority thereof.

                  (e)      Compensation Upon All Other Terminations. If the
Company terminates this Agreement for any reason other than pursuant to Section
4(a)(i), 4(a)(ii), 4(a)(iii) or Section 5(d) or the Executive terminates his
employment for Good Reason, then the Company shall pay the Executive the sum of
(w) the Executive's unpaid salary through the Date of Termination; plus (x) any
bonus compensation earned and unpaid through the Date of Termination; provided,
however, that any bonus compensation conditioned upon the satisfaction of
performance goals shall not be paid unless such performance goals are actually
satisfied; plus (y) the Executive's salary for the Severance Period payable over
the Severance Period in accordance with salary payment practices of the Company
then in effect for active executives; plus (z) the product of (1) a fraction the
numerator of which is the number of months in the Severance Period and the
denominator of which is 12 and (2) the bonus or incentive compensation paid to
the Executive in respect of the most recent fiscal year prior to the year in
which the Date of Termination occurs (payment of which shall be pro-rated over
the Severance Period); and the Executive shall continue to be covered by the
Company's group health, life and disability insurance for the Severance Period
(or in the Company's sole discretion, the Executive shall be provided comparable
coverage or the economic equivalent thereof). If the Executive voluntarily
terminates this Agreement other than for Good Reason, then the Company shall pay
the Executive his salary and any earned but unpaid bonuses through the Date of
Termination, and the Company shall have no further obligations to the Executive
under this Agreement. The "Severance Period" shall be twelve (12) months.

                  (f)      Notwithstanding anything else contained herein, the
obligation of the Company to make any severance payments to the Executive
hereunder shall be conditioned upon the execution and delivery by the Executive
of a release from liability in favor of the Company substantially in the form
attached hereto as Appendix II.

Section 6. Confidentiality.

                  (a)      Each Item, Trade Secret and piece of Confidential
Information (in each case, as defined below) that comes into Executive's
possession by reason of his employment are the property of the Company and shall
not be used by Executive in any

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way except in the course of his employment by, and for the benefit of the
Company. Executive will not remove any Items from premises owned or leased by
the Company except as his duties shall require, and upon termination of his
employment, all Items (including any copies or excerpts thereof) will be turned
over to the Chairman of the Board of the Company.

(b)Executive will preserve as confidential all Confidential Information that has
been or may be obtained by him. Executive will not, without written authority
from the Company, use for his own benefit or purposes, or disclose to others,
either during his employment or for two (2) years thereafter, any Confidential
Information or any copy or notes made from any Item embodying Confidential
Information except as required by his employment with the Company or to the
extent disclosure is or may be required by a statute, by a court of law, by any
governmental agency having supervisory authority over the business of the
Company or by any administrative or legislative body (including a committee
thereof) with jurisdiction to order him to divulge, disclose or make accessible
such information, provided, however, that the Executive shall give the Company
notice of any such request or demand for such information upon his receipt of
same and the Executive shall reasonably cooperate with the Company in any
application the Company may make seeking a protective order barring disclosure
by the Executive. Executive understands that his obligations with respect to
Confidential Information shall continue for two years after termination of his
employment with the Company. These restrictions concerning use and disclosure of
Confidential Information shall not apply to information which is or becomes
publicly known by lawful means, or comes into Executive's possession from
sources not under an obligation of confidentiality to the Company.

                  (b)      Executive agrees to hold in confidence all Trade
Secrets of the Company that came into his knowledge during or in connection with
his employment by the Company and shall not disclose, publish or make use of at
any time after the date hereof such Trade Secrets without the prior written
consent of the Company for as long as the information remains a Trade Secret.

                  (c)      Executive understands that any entrusting of
Confidential Information or Trade Secrets to him by the Company is done in
reliance on a confidential relationship arising out of his employment with the
Company. Executive further understands that Confidential Information or Trade
Secrets that he may acquire or to which he may have access, especially with
regard to research and development projects and findings, formulae, designs,
formulation, processes, the identity of suppliers, customers and patients,
methods of manufacture, and cost and pricing data is of great value to the
Company.

                  (d)      Executive agrees that following termination of his
employment with the Company Executive will, if at all possible before answering
but in any event as soon thereafter as practicable, make every effort to contact
the Company's General Counsel if Executive is served with a subpoena or other
legal process asking for a deposition, testimony or other statement, or other
potential evidence to be used in connection with any lawsuit to which the
Company is a party or involving Executive's employment with the Company or any
Confidential Information or Trade Secret of the

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Company.

                  (e)      For purposes of this Agreement: (i) "Confidential
Information" means information relating to the present or planned business of
the Company which has not been released publicly by authorized representatives
of the Company. Executive understands that Confidential Information may include,
for example, discoveries, inventions, know-how and products, customer, patient,
supplier and competitor information, sales, pricing, cost, and financial data,
research, development, marketing and sales programs and strategies,
manufacturing, marketing and service techniques, processes and practices, and
regulatory strategies. Executive understands further that Confidential
Information also includes all information received by the Company under an
obligation of confidentially to a third party; (ii) "Items" include documents,
reports, drawings, photographs, designs, specifications, formulae, plans,
samples, research or development information, prototypes, tools, equipment,
proposals, marketing or sales plans, customer information, customer lists,
patient lists, patient information, regulatory files, financial data, costs,
pricing information, supplier information, written, printed or graphic matter,
or other information and materials that concern the Company's business that come
into Executive's possession or about which Executive has knowledge by reason of
his employment; and (iii) "Trade Secrets" include all information, including a
formula pattern, process, compilation, program, device, method, or technique
that (A) derives independent economic value, actual or potential, from not being
generally known to, and not being readily ascertainable by proper means by other
persons who can obtain economic value from its disclosure or use, (B) is the
subject of efforts that are reasonable under the circumstances to maintain its
secrecy; and (C) otherwise satisfies the requirements of the Georgia Trade
Secrets Act.

Section 7. Proprietary Information.

                  (a)      All Inventions (as defined below) related to the
present or planned business of the Company, which are conceived or reduced to
practice by Executive, either alone or with others, during the period of his
employment or during a period of one (1) year after termination of such
employment, whether or not done during his regular working hours, are the sole
property of the Company. The provisions of this paragraph shall not apply to an
invention for which no equipment, supplies, facilities or confidential or trade
secret information of the Company was used and which was developed entirely on
Executive's own time, unless (a) the invention relates to (i) the business of
the Company, or (ii) the Executive's actual or demonstrably anticipated research
or development for the Company, or (b) the invention results from any work
performed by Executive for the Company.

                  (b)      Executive will disclose promptly and in writing to
the Company, through his supervisor, all Inventions which are covered by this
agreement, and Executive agrees to assign to the Company or its nominee all his
right, title, and interest in and to such Inventions. Executive agrees not to
disclose any of these Inventions to others, without the express consent of the
Company. Executive will, at any time during or after his employment, on request
of the Company, execute specific assignments in favor of the Company or its
nominee of his interest in and to any of the Inventions

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covered by this agreement, as well as execute all papers, render all assistance,
and perform all lawful acts which the Company considers necessary or advisable
for the preparation, filing, prosecution, issuance, procurement, maintenance or
enforcement of patent applications and patents of the United States and foreign
countries for these Inventions, and for the transfer of any interest Executive
may have. Executive will execute any and all papers and documents required to
vest title in the Company or its nominee in the above Inventions, patent
applications, patents, and interests. Executive understands that if he is not
employed by the Company at the time he is requested to execute any document
under this Section 7(b), Executive shall receive fifty dollars ($50.00) for the
execution of each document, and one hundred fifty dollars ($150.00) per day of
each day or portion thereof spent at the request of the Company in the
performance of acts pursuant to this Section 7(b), plus reimbursement for any
out-of-pocket expenses incurred by Executive at the Company's request in such
performance. Executive further understands that the absence of a request by the
Company for information, or for the making of an oath, or for the execution of
any document, shall in no way be construed to constitute a waiver of the
Company's rights under this agreement. Should the Company be unable to secure
the Executive's signature on any document necessary to apply for, prosecute,
obtain, or enforce any patent, copyright, or other right or protection relating
to any Invention, whether due to the Executive's mental or physical incapacity
or any other cause, the Executive hereby irrevocably designates and appoints the
Company and each of its duly authorized officers and agents as the Executive's
agent and attorney in fact, to act for and in the Executive's behalf and stead
and to execute and file any such document, and to do all other lawfully
permitted acts to further the prosecution, issuance, and enforcement of patents,
copyrights, or other rights or protections with the same force and effect as if
executed and delivered by the Executive.

                  (c)      Executive has disclosed to the Company all continuing
obligations which he has with respect to the assignment of Inventions to any
previous employers, and Executive claims no previous unpatented Inventions as
his own, except for those which have been reduced to practice and which are
shown on a schedule, if any, attached to this agreement. Executive understands
that the Company does not seek any confidential or trade secret information
which Executive may have acquired from a previous employer, and Executive will
not disclose to or utilize any such information on behalf of the Company.

                  (d)      All writings and other works which may be copyrighted
(including computer programs) which are related to the present or planned
business of the Company and are prepared by Executive during his employment by
the Company shall be, to the extent permitted by law, works made for hire, and
the authorship and copyright of the work shall be in the Company's name. To the
extent that such writings and works are not works for hire, Executive agrees to
the wavier of "moral rights" in such writings and works, and to assign to the
Company all Executive's right, title and interest in and to such writings and
works, including copyright.

                  (e)      Executive will permit the Company and its agents to
use and distribute any pictorial images which are taken of him during his
employment by the Company as often as desired for any lawful purpose. Executive
waives all rights of prior

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inspection or approval and release the Company and its agents from any and all
claims or demands which Executive may have on account of the lawful use of
publication of such pictorial images.

                  (f)      For purposes of this Agreement, "Invention" shall
mean all ideas, potential marketing and sales relationships, inventions,
experiments, copyrightable expression, research, plans for products or services,
marketing plans, reports, strategies, processes, computer software (including,
without limitation, source code), computer programs, original works of
authorship, characters, know-how, trade secrets, information, data,
developments, discoveries, improvements, modifications, technology, algorithms,
database schema, designs, and drawings, whether or not subject to patent or
copyright protection, made, conceived, expressed, developed, or actually or
constructively reduced to practice by the Executive solely or jointly with
others prior to or during the Term, which refer to, are suggested by, or result
from any work which (i) the Executive has performed prior to the Term of this
Agreement, (ii) the Executive may perform during his employment, or (iii) from
any information obtained from the Company or any affiliate of the Company, and
shall not be limited to the meaning of "Invention" under the United States
patent laws.

Section 8. Agreement Not to Compete.

                  (a)      While employed by the Company and for a period equal
to the greater of (x) one (1) year and (y) the severance period (or the deemed
severance period set forth in clause z(A) of the first sentence of Section
5(d)(i) in the event of a termination of employment upon a Change of Control)
thereafter, the Executive shall not, directly or indirectly, anywhere in the
United States:

                           (i)      render services which are substantially
         similar to the services performed by Executive for the Company during
         the last year of the Term of this Agreement to any person, corporation,
         partnership or other entity which competes with the Company (or any
         subsidiary) in the business of developing or manufacturing
         antibody-based immunotherapeutics to prevent or treat infections caused
         by staphylococcal or fungal organisms;

         Executive agrees that this covenant is especially appropriate because,
         if he worked for a competitor, he would inevitably make business
         decisions by relying on his knowledge of the Company's Confidential
         Information and Trade Secrets; thus, he would inevitably provide
         competitors with the Company's Confidential Information and Trade
         Secrets. The Company's Confidential Information and Trade secrets are
         not generally known by others in the industry, and they would provide
         an unfair advantage for competitors. Further, the Company recognizes
         that there are some companies who provide many products and services,
         some of which may be competitive and some which may not be.
         Accordingly, this covenant only prohibits Executive from performing the
         same or substantially the same services for that section, division,
         group, subsidiary, affiliate or operating unit of a competitor that
         actually develops or manufactures antibody-based immunotherapeutic
         products to prevent or treat infections caused

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         by staphylococcal or fungal organisms;

                           (ii)     solicit for employment of any person who was
         employed by the Company (or any subsidiary) during the Executive's
         employment with the Company and with whom the Executive had contact
         during the last year of his employment with the Company; or

                           (iii)    call on or solicit, directly or indirectly
         for the purpose of providing immunotherapeutics (and related services)
         to prevent or treat infections caused by staphylococcal or fungal
         organisms, any person or entity known by the Executive to be a customer
         of the Company (or of any subsidiary), or with which the Company (or
         any subsidiary) was in negotiations to become a customer of the Company
         (or such subsidiary), as the case may be, during the Executive's
         employment with the Company, and with whom the Executive had direct
         contact. For purpose of this section, "contact" means interaction
         between the Executive and the client within the last year of
         Executive's employment to further the business relationship or perform
         services for the client, and interaction between the Executive and
         prospective client within the last year of Executive's employment to
         develop a business relationship.

                  (b)      If any of the restrictions contained in this Section
8 shall be deemed by any court of competent jurisdiction to be unenforceable by
reason of the extent, duration or geographical scope thereof, or otherwise, then
the parties agree that such court shall modify such restriction, only to the
extent necessary to render it enforceable and, in its reduced form, such
restriction shall then be enforced, and in its reduced form this Section 8 shall
be enforceable in the manner contemplated hereby.

Section 9. Company Resources.

         Executive may not use any of the Company's (or any affiliate's)
equipment for personal purposes without written permission from the Company. The
Executive may not give access to the Company's (or any affiliate's) offices or
files to any person not in the employ of the Company without written permission
of the Company.

Section 10. Injunctive Relief.

         Executive understands and agrees that the Company will suffer
irreparable harm in the event that the Executive breaches any of the Executive's
obligations under Sections 6, 7, 8 or 9 hereof and that monetary damages will be
inadequate to compensate the Company for such breach. Accordingly, the Executive
agrees that, in the event of a breach or threatened breach by the Executive of
any of the provisions of Sections 6, 7, 8 or 9 hereof, the Company shall be
entitled to appropriate injunctive relief, in addition to any other in addition
to any other rights, remedies or damages available to the Company at law or in
equity.

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Section 11. Severability.

         In the event any of the provisions of this Agreement shall be held by a
court or other tribunal of competent jurisdiction to be unenforceable, the other
provisions of this Agreement shall remain in full force and effect.

Section 12. Survival.

         Sections 1(d) and 4 through 16 shall survive the termination of this
Agreement for any reason.

Section 13. Representations, Warranties, and Covenants.

         Executive represents, warrants, and covenants that the Executive's
performance of all the terms of this Agreement and any services to be rendered
as an employee of the Company do not and will not breach any fiduciary or other
duty or any covenant, agreement or understanding (including, without limitation,
any agreement relating to any proprietary information, knowledge or data
acquired by the Executive in confidence, trust or otherwise prior to the
Executive's employment by the Company) to which the Executive is a party or by
the terms of which the Executive may be bound. The Executive further covenants
and agrees not to enter into any agreement or understanding, either written or
oral, in conflict with the provisions of this Agreement.

Section 14. Accounting for Profits; Indemnification.

         Executive covenants and agrees that, if the Executive shall violate any
of the Executive's covenants or agreements contained in Sections 6, 7, 8 or 9
hereof, the Company shall be entitled to an accounting and repayment of all
profits, compensation, royalties, commissions, remunerations or benefits which
the Executive directly or indirectly shall have realized or may realize relating
to, growing out of or in connection with any such violation; such remedy shall
be in addition to and not in limitation of any injunctive relief or other rights
or remedies to which the Company is or may be entitled at law or in equity or
otherwise under this Agreement. The Executive hereby agrees to defend, indemnify
and hold harmless the Company against and in respect of: (a) any and all losses
and damages resulting from, relating or incident to, or arising out of any
misrepresentation or breach by the Executive of any of the Executive's
representations, warranties, covenants or agreements made or contained in this
Agreement; and (b) any and all actions, suits, proceedings, claims, demands,
judgments, costs and expenses (including reasonable attorneys' fees) incident to
the foregoing.

Section 15. General.

         This Agreement supersedes and replaces any existing agreement between
the Executive and the Company relating generally to the same subject matter, and
may be modified only in a writing signed by the parties hereto. Failure to
enforce any provision of the Agreement shall not constitute a waiver of any term
herein. The Executive agrees that he will not assign, transfer, or otherwise
dispose of, whether voluntarily or involuntarily, or by operation of law, any
rights or obligations under this Agreement.

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Any purported assignment, transfer, or disposition shall be null and void.
Nothing in this Agreement shall prevent the consolidation of the Company with,
or its merger into, any other corporation, or the sale by the Company of all or
substantially all of its properties or assets, or the assignment by the Company
of this Agreement and the performance of its obligations hereunder. Subject to
the foregoing, this Agreement shall be binding upon and shall inure to the
benefit of the parties and their respective heirs, legal representatives,
successors, and permitted assigns, and shall not benefit any person or entity
other than those enumerated above. The use of any gender herein shall be
applicable to all genders.

Section 16. Executive Acknowledgment.

         Executive acknowledges (a) that he has consulted with or has had the
opportunity to consult with independent counsel of his own choice concerning
this Agreement and has been advised to do so by the Company, and (b) that he has
read and understands the Agreement, is fully aware of its legal effect, and has
entered into it freely based on his own judgment.

                   [Signatures appear on the following page.]

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AGREED TO BY:

                                           INHIBITEX, INC.

 /s/ William D. Johnston                   /s/ Michael Henos
---------------------------                ------------------
William D. Johnston                        Michael Henos
                                           Chairman of the Board

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                                   APPENDIX I

                                 JOB DESCRIPTION

The Chief Executive Officer (CEO) will report to the Board of Directors and will
be responsible for all aspects of the company. He will serve as a business
partner to the Board of Directors and other members of the executive team. Also,
the CEO will provide leadership and direction to ensure the development of
relevant business information and continued growth for the company consistent
with the plans accepted by the Board of Directors.

                                                  Inhibitex, Inc.

                                              By: /s/ Michael Henos
                                                  -----------------
                                                    Michael Henos

                                                  /s/ William D. Johnston
                                                  -----------------------
Date: 2/20/04                                       William D. Johnston

                                       A-1