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                                                                   Exhibit 10.18

CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED BY
ASTERISKS, HAS BEEN OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND
EXCHANGE COMMISSION PURSUANT TO RULE 406 UNDER THE SECURITIES ACT OF 1933.

                 LICENSE AND DEVELOPMENT COLLABORATION AGREEMENT

         This License and Research Collaboration Agreement (the "Agreement"),
effective as of the last signature date below (the "Effective Date"), is entered
into by and between American Home Products Corporation ("AHPC"), acting through
its Wyeth-Ayerst Laboratories Division, Wyeth-Lederle Vaccines business unit, a
Delaware corporation with a place of business at 211 Bailey Road, West
Henrietta, New York 14586 (hereinafter, together with AHPC's wholly-owned
affiliates and subsidiaries, collectively referred to as "WLV") and Inhibitex,
Inc. a Delaware corporation with its principal place of business at 8995
Westside Parkway Suite 150, Alpharetta, GA 30004 (hereinafter "INX").

         INX has substantial knowledge and expertise in and holds significant
intellectual property rights in MSCRAMMTM proteins (Microbial Surface Components
Recognizing Adhesive Matrix Molecules) as the result of (1) a sublicense dated
June 28, 1994 from The Texas A & M University Systems (hereinafter "TAMUS")
through its licensee, AM Fund I, L.P.; (2) an assignment dated March 25, 1998
from Magnus Hook; (3) a license dated April 8, 1999 from BioResearch Ireland
(hereinafter "BRI"); and (4) a license dated February 4, 2000 from TAMUS.

         WLV is a worldwide leader in the development and commercialization of
human vaccines.

         The parties desire to enter into an agreement whereby WLV obtains (1) a
worldwide license under INX's Staphylococcus aureus and Staphylococcus
epidermidis MSCRAMMTM technology for the development and commercialization of
human vaccines, and (2) the opportunity to collaborate in the development of
this technology.

         In consideration of the foregoing premises and the covenants contained
herein, the parties agree as follows:

ARTICLE I - DEFINITIONS

         For purposes of this Agreement, the terms defined in this Article 1
shall have the meanings set forth below:

         1.1      "Affiliate" shall mean, with respect to WLV or INX, any
corporation, partnership or other business entity controlled by, controlling, or
under common control with it. However, for the purposes of this Agreement, the
term "Affiliate" shall not include subsidiaries or other entities in which WLV
owns a majority of the ordinary voting power to elect the majority of the board
of directors or other governing board but is otherwise restricted from electing
such majority by contract or otherwise, until such time as (a) such restrictions
are no longer in effect, or (b) the subsidiary or other entity is otherwise
designated by WLV in writing as being an Affiliate for purposes hereunder.

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"Affiliate" shall include but not be limited to divisions and subsidiaries, and
in the case of WLV, shall include its parent company and all entities which are
Affiliates of the parent company.

         1.2      "BLA" shall mean a biologics license application or equivalent
filed with the FDA or an equivalent regulatory body outside the U.S. for
approval of manufacturing and sale of any Product.

         1.3      "Completion of Clinical Trial" shall mean the date on which
the treatment of last patient in the first Clinical Trial is completed.

         1.4      "Confidentiality Agreement" shall mean the Confidentiality
Agreement between INX and WLV dated August 12, 1999.

         1.5      "Confidential Information" shall mean information or data
described in Article 5 below.

         1.6      "Development Collaboration Plan" shall mean the written
document describing the Development Collaboration Program to be performed by INX
and WLV, as approved by the Development Committee from time to time, as
described in Article 4. The current form of the Development Collaboration Plan
is attached hereto as Exhibit C.

         1.7      "Development Collaboration Program" shall mean a program for
the development of Licensed Products through preclinical and clinical
development by INX and WLV.

         1.8      "Development Committee" shall mean the development committee
composed of representatives of INX and WLV described in Article 4 below.

         1.9      "FDA" shall mean the United States Food and Drug
Administration.

         1.10     "Field" shall mean human vaccines for containing MSCRAMM(TM)
proteins derived from S. aureus and S. epidermidis for the prevention of S.
aureus and S. epidermidis infections, provided, however that the Field shall
exclude the use of MSCRAMM(TM) proteins or such vaccines to stimulate antibody
titer in plasma donors whose plasma is collected for the purpose of developing
and commercializing products containing plasma derived immunoglobulin.

         1.11     "First Commercial Sale" shall mean the first sale for use or
consumption by the general public of a Licensed Product in a country after any
required marketing and pricing approval (where necessary) has been granted by
the governing health authority of such country.

         1.12     "IND" shall mean an Investigational New Drug Application as
filed by or on behalf of WLV.

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         1.13     "Inventions" shall mean all inventions, discoveries,
improvements or other technology, including biologics, conceived or reduced to
practice under the Development Collaboration Program solely or jointly by
employees or others acting on behalf of WLV or INX or their Affiliates.
Inventorship shall be determined in accordance with U.S. laws of inventorship.

         1.14     "INX Inventions" shall mean Inventions conceived or reduced to
practice by employees or others acting on behalf of INX or its Affiliates.

         1.15     "INX Know How" shall mean all proprietary and confidential
information and data including, but not limited to, compositions, formulae,
procedures, protocols, techniques and results of experimentation and testing,
and all biologics or technology, including, but not limited to, cells, cell
lines, genes, and proteins which are necessary or useful to practice any process
or method related to, or to make, use or sell any Licensed Product in the Field,
including but not limited to any methods for manufacture or use of cells or cell
lines or proteins contained in a Licensed Product, which INX owns or in which
INX has an interest, and which is in the possession of INX on the date of this
Agreement or thereafter, all to the extent and only to the extent that INX
hereafter will have the right to grant licenses or other rights thereunder.

         1.16     "INX Patent Rights" shall mean:

                  (a)      the patent and patent applications listed in Exhibit
B hereto, which shall be updated by INX as appropriate from time to time, all
patent applications heretofore or hereafter filed or having legal force in any
country owned by or licensed to INX or to which INX otherwise acquires rights,
which claim a composition, method or process for biologics or technology,
including, but not limited to, cells, cell lines, genes, peptides and proteins
which are necessary or useful to practice any process or method related to, or
to make, use or sell any Licensed Product in the Field, including Inventions,
together with any and all patents that have issued or in the future issue
therefrom, including utility, model and design patents and certificates of
invention, and

                  (b)      all divisionals, continuations,
continuations-in-part, continued prosecution applications, requests for
continued examination, reissues, renewals, extensions or additions to any such
patents and patent applications; all of Section (a) and this Section (b) of this
paragraph to the extent and only to the extent that INX hereafter will have the
right to grant licenses, immunities or other rights thereunder, and any foreign
counterparts to those patents and patent applications, and currently consisting
of the INX Patent Rights described on Exhibit B hereto.

                  (c)      Patents and patent applications licensed to INX by a
Third party or to which INX otherwise acquires rights after the effective date
of this Agreement shall become part of the INX Patent Rights to the extent that
INX has the right to grant licenses to WLV in the Field and only to the extent
that INX is able to do so on economic terms substantially similar to the
economic terms of its primary licenses from third parties as of the effective
date.

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         1.17     "Joint Invention" shall mean an Invention invented jointly by
one or more employees or others acting on behalf of WLV or its Affiliates and by
one or more employees or others acting on behalf of INX or its Affiliates under
the Development Collaboration Program. Inventorship shall be determined in
accordance with U.S. laws of inventorship.

         1.18     "Joint Patent Rights" shall mean:

                  (a)      all patent applications hereafter filed or having
legal force in any country owned jointly by INX and WLV or to which INX and WLV
otherwise acquire joint rights, which claim a Joint Invention, together with any
and all patents that issue therefrom, including utility, model and design
patents and certificates of invention, and

                  (b)      all divisionals, continuations,
continuations-in-part, continued prosecution applications, requests for
continued examination, reissues, renewals, extensions or additions to any such
patents and patent applications and any foreign counterparts to those patents
and patent applications.

         1.19     "Licensed Product" shall mean active human vaccines containing
MSCRAMM(TM) proteins derived from S. aureus or S. epidermidis, within the Field
the manufacture, use or sale of which, but for the license granted herein, would
infringe at least one Valid Claim of INX Patent Rights, or utilize INX Know-How.

         1.20     "Licensed Technology" shall mean the INX Patent Rights and the
INX Know-How.

         1.21     "Net Sales" shall mean the amount bill or invoiced on account
of all sales of Licensed Products to an independent Third Party by WLV or its
Affiliates or sublicensees in bona fide arms' length transactions, less the
following deductions:

         (a)      trade and/or quantity discounts actually taken by the customer
                  in such amounts as are customary in the trade;

         (b)      any tax, excise, or other governmental charges upon or
                  measured by the production, sales, transportation, delivery or
                  use of said Licensed Products contained therein (Income taxes
                  owed or paid by WLV shall not be deducted from Net Sales.);

         (c)      transportation charges and discounts other than those
                  described above;

         (d)      ordinary and customary sales commissions actually paid to
                  non-affiliated third Parties;

         (e)      amounts repaid or credited by reason or rejections recall,
                  destruction or return or because of price rebates;

         (f)      taxes paid by WLV or its Affiliates or sublicensees to the
                  United States Government or an instrumentality thereof under
                  42 U.S.C. 300 aa-1 et seq. or other similar legislation, or to
                  a State of the United States or to a government of any other
                  country or portion thereof insuring against liability arising
                  out of the manufacture, use or sale of a Licensed Product by
                  WLV or its Affiliates or sublicensees; and

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         (g)      reserves reasonably set aside by WLV as a self-insurance fund
                  insuring against liability arising out of WLV's manufacture,
                  use or sale of a Licensed Product, provided, however, that WLV
                  agrees if the reserves are reduced or eliminated or if at the
                  time WLV discontinues the sale of a Licensed Product there
                  remain funds in the set aside account as aforesaid, then WLV
                  will account to INX for the amount of the reduction,
                  elimination or unexpired reserve, as the case may be, and will
                  pay a royalty to INX on said amount as though said amount
                  represented income from sales of a Licensed Product. WLV
                  represents that the withholding of such reserves is not
                  generally carried out in the normal course of the selling of
                  its current line of vaccine products, and, with respect to
                  Licensed Products hereunder, WLV will not withhold such
                  reserves in the absence of outstanding liability claims or the
                  reasonable anticipation of such claims arising within the next
                  royalty payment period.

         1.22     "Person" shall mean an individual, corporation, partnership,
trust, business trust, association, joint stock company, joint venture, pool,
syndicate, sole proprietorship, unincorporated organization, governmental
authority or any other form of entity not specifically listed herein.

         1.23     "Regulatory Approval" shall mean, in any given country in
which a Licensed Product is or is to be manufactured, sold or distributed, the
approval of all government authorities necessary to permit the manufacture, sale
or distribution of the Licensed Product. In the United States, Regulatory
Approval shall include, without limitation, BLA Approval, to the extent
required.

         1.24     "Third Party" shall mean any Person other than INX, WLV and
their respective Affiliates.

         1.25     "Valid Claim" shall mean a claim of any pending application or
any issued and unexpired patent within the INX Patent Rights, so long as such
claim shall not have been disclaimed or shall not have been held invalid in a
final decision rendered by a tribunal of competent jurisdiction from which no
appeal has been or can be taken.

ARTICLE 2 - LICENSE GRANT, FEES AND ROYALTIES

         2.1      License to WLV. For the term of this agreement, INX hereby
grants to WLV a worldwide, exclusive (even as to INX), royalty-bearing license
in the Field, including the right to grant sublicenses, under the INX Patent
Rights, the INX ownership interest in Joint Patent Rights, INX Know-How and INX
Inventions to make, have made, have used, sell, have sold, offer for sale, and
import Licensed Products in the Field. WLV shall not make, use, sell market or
promote Licensed Product for use outside the Field. Where the INX Patent Rights
are themselves licensed from a Third Party, WLV's license shall take the form of
a sublicense.

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         2.2      Reservation of Rights. TAMUS and BRI each retains an
irrevocable, nonexclusive and nontransferable royalty-free right to use the
Licensed Technology for its own educational and non-commercial research
purposes. Pursuant to 37 C.F.R. 401.14, the U.S. Government shall have a
nonexclusive, nontransferable, irrevocable, paid-up license to practice or have
practiced for or on behalf of the United States the Licensed Technology
throughout the world.

         2.3      Fees and Royalties. In consideration of both the license
granted in Section 2.1 and INX's contributions to the Development Collaboration
described in Article 4 herein, WLV agrees to make (1) the up front license fee
payments as set forth in this Article 2.3, (2) the annual license and
development support fee payments as set for below in this Article 2.4, (3) the
earned royalty payments as set forth below in this Article 2.5, and (4) the
special development payments set forth in Exhibit A attached hereto.

         2.4      Up Front license Fee. An up front license fee payment of one
and one half million dollars ($1,500,000) shall be made upon execution of this
agreement. In the event that Hart-Scott-Rodino approval is not obtained in
accordance with Article 14.9 hereof, INX shall refund to WLV the $1,500,000 paid
under this Article 2.4.

         2.5      Annual License and Development Support Fees. During the term
of this agreement, and continuing until the First Commercial Sale of Licensed
Product in the United States or any other country where royalty payments exceed
[ *** ], WLV shall make a minimum annual license and development support fee
payment of [ *** ] per year, commencing on the Effective Date of this Agreement,
payable at the rate of [ *** ] at the start of each calendar quarter. For the
first year of this Agreement, the entire payment of [ *** ] shall be made within
30 days after execution of this Agreement. To the extent that the parties have
agreed to a Development Collaboration Plan as set forth below in Article 4, the
annual license and development support payments shall be applied to effect the
Development Collaboration Plan at the rate of [ *** ] per FTE (Full Time
Equivalent employee) per year. The foregoing minimum annual license and
development support payments are due regardless of whether a Development
Collaboration Plan has been agreed to and regardless of whether WLV desires to
support development at INX. In addition to the foregoing minimum annual license
and development support payments, WLV shall have the right but no obligation to
request, at least ninety days prior to the start of each calendar year, that
additional development support at INX be funded by WLV for up to two additional
FTE's at the rate of [ *** ] per FTE per year. Unless otherwise agreed to in
writing by the Parties, the maximum number of FTE's to be supported at INX under
the Development Collaboration Plan shall be four FTE's. A change in the maximum
number of FTE's shall be made only by written agreement of the parties and only
if additional funds are provided by WLV to support such additional FTE's.

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         2.6      Earned Royalties on Net Sales.

         (a)      When the manufacture or sale or distribution of Licensed
Products are covered by a Valid Claim of INX Patent Rights and/or INX's interest
in Joint Patent Rights, WLV shall pay to INX an earned royalty, on a
country-by-country basis, equal to [ *** ] of Net Sales of Licensed Product on a
country-by-country basis, beginning upon the First Commercial Sale and
continuing until the expiration of the last to expire of the INX Patent Rights
and INX's interest in Joint Patent Rights in such country.

         (b)      In countries where the manufacture or sale or distribution of
Licensed Products is not covered by a Valid Claim of INX Patent Rights and/or
INX's interest in Joint Patent Rights, if a Licensed Product incorporates INX
Know-How, WLV shall pay to INX an earned royalty of [ *** ] of Net Sales of
Licensed Product, beginning upon the First Commercial Sale in said country and
continuing for a period of five (5) years thereafter.

         (c)      However, if a Licensed Product is manufactured in a country
where the Licensed Product is covered by a Valid Claim of INX Patent Rights
and/or INX's interest in Joint Patent Rights, and then is sold in a country
where no patent applications were filed or no patents ever issue, WLV shall pay
to INX the earned royalty in accordance with Section 2.6(a). In any event, only
one (1) earned royalty shall be due per Licensed Product under Section 2.6(a) or
(b).

         2.7      Time of Payments. The earned royalty shall be paid quarterly
starting with the end of the calendar quarter following the First Commercial
Sale and shall be made not more than one (1) month following the end of each
such quarter. WLV agrees to make payment to INX by wire transfer as specified by
INX. WLV agrees to submit to INX, at the time of each royalty payment, a written
report showing, on a country-by-country basis, the calculation of Net Sales of
Licensed Products for a quarter, including all currency conversions.

         2.8      Currency for Payment. All payments made to INX pursuant to
this Agreement, shall be made in United States Dollars. Royalty payments shall
first be calculated in the currency of the country in which sales took place and
then directly converted to U.S. Dollars using the average of the exchange rates
applicable on the date of payment used by WLV for financial accounting purposes
in accordance with generally accepted accounting principles.

         2.9      If by reason of any restrictive exchange laws or regulations,
WLV shall be unable to convert to U.S. dollars amounts equivalent to the earned
royalty payable by WLV hereunder in respect of Licensed Products sold for funds
other than U.S. dollars, WLV shall notify INX promptly with an explanation of
the circumstances. In such event, all royalties due hereunder in respect of the
transaction so restricted (or the balance thereof due hereunder and not paid in
funds other than U.S. dollars as hereinafter provided) shall be deferred and
paid in U.S. dollars as soon as reasonable possible after, and to the extent

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that such restrictive exchange laws or regulations are lifted so as to permit
such conversion to U.S. dollars, of which lifting WLV shall promptly notify INX.
At its option INX shall meanwhile have the right to request the payment (to it
or to a nominee), and upon such request, WLV shall pay, or cause to be paid, all
such amounts (or such portions thereof as are specified by INX) in funds, other
than U.S. dollars, designated by INX and legally available to INX under such
then existing restrictive exchange laws or regulations.

         2.10     If in any country where Licensed Products are sold, rates of
royalties provided for herein are prohibited by law or regulation,, WLV shall
pay royalties to IX at the highest rate permitted in that country for licenses
of the type herein granted. If this royalty payment falls below the payment INX
is required to pay its licensors, WLV will pay INX the difference.

         2.11     Any and all taxes levied on account of royalties paid from a
country in which a provision is made in the law or by regulation for withholding
shall be deducted from such royalty paid to INX hereunder and proof of payment
of such taxes shall be secured and reported in the quarterly reports as set
forth in Section 2.7. If, after deductions, this royalty payment falls below the
payment INX is required to pay its licensors, WLV will pay INX the difference.

         2.12     Books and Records. WLV shall keep full and accurate records
and books of account containing all particulars necessary for showing the
amounts of royalties due INX hereunder. At all reasonable times for a period of
not more than three (3) years after the end of each reporting year, not to
exceed once each year, the books and records relating to sales of the Licensed
Product shall be open to inspection by INX or its independent Certified Public
Accountants reasonably acceptable to WLV, who may make such confidential
inspection of such records and books of account as is necessary to verify the
computation of royalties due to INX. The fees charged by such Certified Public
Accountants shall be paid by INX unless it is determined in the audit that the
WLV payments for the audited period are in error in INX's favor by an amount in
excess of five percent (5%) of the total royalties paid for the audited period.
Any payment owed shall be paid within thirty (30) days plus interest at the then
prevailing prime interest rate plus one percent (1%). In accordance with Article
5, INX agrees to hold such records and independent accounting reports strictly
confidential, and agrees to cause such independent certified public accountant
to hold such records strictly confidential, except as may be necessary to
maintain an action against WLV for breach of this Agreement. This Section shall
survive termination of this Agreement.

         2.13     Direct Licenses to Affiliates. WLV may at any time following
or at the time of the initiation of sales in a given geography (country or
region, e.g., the European Union) request and authorize INX to grant licenses
directly to Affiliates of WLV in such geography by giving written notice to INX
designating to whom a direct license is to be granted by INX. Upon receipt of
any such notice, INX shall enter into a separate direct license agreement with
each WLV Affiliate designated by WLV in such notice and the exclusive license
shall convert to a co-exclusive license. All such direct license agreements
shall include all of the terms of this Agreement, including Section 2.15
"Minimum

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Diligence" below, (except those terms pertaining to development of Licensed
Products), except for such modifications as may be required by the laws and
regulations in the country in which the direct license agreement is to be
performed, provided that any such direct licenses are consistent with the
economic terms and intent of this Agreement. In countries where validity of the
direct license agreement requires prior governmental approval or registrations,
such direct license agreements shall not become binding between the Parties
thereto until such approval or registration is granted. Upon termination of this
Agreement without cause by WLV, no existing direct licenses granted to WLV
Affiliates shall be affected by such termination, and all such direct licenses
to Affiliates shall remain in effect according to their terms, provided that
such termination of this Agreement and continuation of the direct licenses is
consistent with the economic terms and intent of this Agreement. INX shall
continue to be entitled to payments under such direct licenses to Affiliates
pursuant to this Article 2.

         2.14     Diligence. WLV agrees to use reasonable commercial efforts to
pursue the pre-clinical and clinical development, governmental approval,
manufacturing, marketing and sales of Licensed Products. As used herein,
"reasonable commercial efforts" shall mean efforts which are consistent with
those utilized by WLV for its own internally developed vaccine products of
similar market potential at a similar stage of such product life, taking into
account the existence of other competitive products in the marketplace or under
development, the proprietary position of the product, the profitability of the
product, regulatory considerations and other commercially or scientifically
relevant factors. In addition, the obligations of WLV with respect to a given
Licensed Product are expressly conditioned upon the safety, efficacy, or
commercial feasibility of that Licensed Product, and such obligations may be
delayed or suspended for so long as any condition or event exists which
reasonably causes WLV to question the safety, efficacy or commercial feasibility
of that Licensed Product. Provided that WLV markets a Licensed Product in any
one of U.S., Germany, France, Great Britain, or Japan, WLV's obligation to
market a Licensed Product shall not apply in any country if WLV has not
commenced or has ceased marketing such Licensed Product in the country in
question substantially due to adverse business, regulatory or financial
conditions which would cause the marketing of such Licensed Product in such
country to be contrary to the commercial best interests of WLV.

         2.15     Minimum Diligence.

         (a)      In the event that a Phase I clinical trial of a Licensed
Product has not been initiated anywhere in the world as of the sixth (6th)
anniversary of the Effective Date, the annual License and Development Support
Fee described in Section 2.4 above shall increase to [ *** ], which shall remain
the annual amount due until First Commercial Sale of a Licensed Product in the
United States or any other country where royalty payments will equal at least
[***].

         (b)      In the event that a Phase I clinical trial of a Licensed
Product has not been initiated anywhere in the world as of the eighth (8th)
anniversary of the Effective Date, and only if WLV has by that time initiated a
Phase I clinical trial of a vaccine product other than a Licensed Product which
has essentially the same medical indication and could compete in essentially the
same market as a Licensed Product, then INX shall have the

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right to terminate this Agreement including the licenses granted herein on
thirty (30) days written notice.

         (c)      In the event that a Phase I clinical trial of a Licensed
Product has not been initiated anywhere in the world as of the tenth (10th)
anniversary of the Effective Date, then INX shall have the right to terminate
this Agreement including the licenses granted herein on thirty (30) days written
notice.

         2.16     Section 365(n) of the Bankruptcy Code. All rights and licenses
granted under or pursuant to any section of this Agreement are, and shall
otherwise be, deemed to be, for purposes of Section 365(n) of the Bankruptcy
Code, licenses of rights to "intellectual property" as defined under Section
101(35A) of the Bankruptcy Code. The parties shall retain any may fully exercise
all of their respective rights and elections under the Bankruptcy Code.

ARTICLE 3 - REPRESENTATIONS AND WARRANTIES

         3.1      Corporate Existence and Power. As of the Effective Date and
during the term of this Agreement each party represents and warrants that it:

                  (a)      is a corporation duly organized, validly existing and
in good standing under the laws of the state in which it is incorporated;

                  (b)      has the corporate power and authority and the legal
right to own and operate its property and assets, to lease the property and
assets it operates under lease, and to carry on its business as it is now being
conducted; and

                  (c)      is in compliance with all requirements of applicable
law, except to the extent that any noncompliance would not have a material
adverse effect on the properties, business, financial or other condition of such
party and would not materially adversely affect such party's ability to perform
its obligations under this Agreement.

         3.2      Authorization and Enforcement of Obligations.

                  (a)      As of the Effective Date and during the term of this
         Agreement each party represents and warrants that it:

                  (i)      has the corporate power and authority and the legal
right to enter into this Agreement and to perform its obligations hereunder, and

                  (ii)     has taken all necessary corporate action on its part
to authorize the execution and delivery of this Agreement and the performance of
its obligations hereunder. This Agreement has been duly executed and delivered
on behalf of such party, and constitutes a legal, valid, binding obligation,
enforceable against such party in accordance with its terms.

                  (b)      INX warrants that it has the authority and right to
convey to WLV the rights granted under this Agreement, including but not limited
to the rights set forth in Article 2.

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         3.3      Consents. As of the Effective Date and during the term of this
Agreement each party represents and warrants that all necessary consents,
approvals, and authorizations of all governmental authorities and other Persons
required to be obtained by such party in connection with entering into this
Agreement have been obtained.

         3.4      No Conflict. As of the Effective Date and during the term of
this Agreement each party represents and warrants that the execution and
delivery of this Agreement, including the grant of licenses or sublicenses
hereunder, and the performance of such party's obligations hereunder:

                  (a)      do not and will not conflict with or violate any
requirement of applicable laws or regulations or with any contractual obligation
of such party, and

                  (b)      do not and will not conflict with, or constitute a
default or require any consent under, any contractual obligation of such party.

         3.5      Regulatory Compliance. WLV, in its capacity as a manufacturer,
distributor and seller of Licensed Products, represents and warrants that the
Licensed Products, as of the date of shipment, are not adulterated or
misbranded, will be in full compliance with applicable laws and regulations of
the United States Federal Food, Drug and Cosmetic Act and any similar applicable
foreign, federal, state or local laws or regulations and will not constitute
articles which may not under the provisions of such Act, be introduced into
interstate commerce.

         3.6      DISCLAIMER OF WARRANTIES. NOTHING IN THIS AGREEMENT SHALL BE
CONSTRUED AS A REPRESENTATION MADE, OR WARRANTY GIVEN, BY EITHER PARTY THAT ANY
PATENT WILL ISSUE BASED UPON ANY PENDING PATENT APPLICATION WITHIN THE PATENT
RIGHTS, THAT ANY PATENT WITHIN THE PATENT RIGHTS WHICH ISSUES WILL BE VALID OR
THAT THE EXERCISE OF ANY LICENSE OR PATENT RIGHTS GRANTED HEREUNDER WILL NOT
INFRINGE THE PATENT OR PROPRIETARY RIGHTS OF ANY OTHER PERSON. IN THIS REGARD,
INX REPRESENTS THAT IT HAS TURNED OVER TO WLV THE RESULTS OF ITS SEARCH OF THIRD
PARTY PATENTS. NO REPRESENTATION OR WARRANTY IS MADE REGARDING THE EFFICACY OF
THE TECHNOLOGY DESCRIBED IN THE PATENT RIGHTS. FURTHERMORE, EXCEPT AS EXPRESSLY
SET FORTH HEREIN, NEITHER PARTY MAKES ANY REPRESENTATIONS OR WARRANTIES, EXPRESS
OR IMPLIED, WITH RESPECT TO THE PATENT RIGHTS, INCLUDING WITHOUT LIMITATION, ANY
WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.

ARTICLE 4 - DEVELOPMENT COLLABORATION

         4.1      Development Collaboration Program: Performance by INX and WLV.
From the Effective Date and in accordance with the terms of this Agreement, INX
and WLV each agree to perform, or have performed, the Development Collaboration
Program as

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approved and agreed to by the Development Committee for the development of
Licensed Product(s) through preclinical and clinical trials. Each party shall be
obligated to perform, or have performed, such work as they have each proposed in
accordance with the Development Collaboration Plan, provided, however, that the
obligations of INX to perform such work shall be limited to the FTE's supported
by the development and support fees paid by WLV.

         4.2      Development Committee Role, Decisions. The Development
Committee shall determine and monitor the Development Collaboration Program,
including making recommendations regarding the performance of the Development
Collaboration Plan and generally on the conduct of research and development
under this Agreement. The Development Committee shall approve all modifications
to the Development Collaboration Plan, and shall carry out such other activities
as the parties may agree to. At each meeting of the Development Committee it
shall evaluate the progress of the Development Collaboration Program and
determine whether it is reasonable to believe that the endpoints set forth in
the Development Collaboration Plan are likely to be achieved in the time
specified. It is expected (but not required) that any decisions made or actions
taken by the Development Committee shall be made unanimously by its members.
Each committee member shall have one vote. As development of the Licensed
Product proceeds toward human clinical trials, the Development Committee shall
be replaced with a Management Committee that will meet at least twice each year
to determine, manage and oversee the clinical phases of development and
determine, manage and oversee the regulatory approval process for the Licensed
Product.

         4.3      Development Committee Membership. Within ten (10) days of the
Effective Date, INX and WLV shall each appoint two people (or such other number
of persons as the parties may determine) to serve on a committee for the
Development Collaboration Program (the "Development Committee"). Such persons
must be employees of either WLV or INX, or, if not employees of INX or WLV, such
members must be approved in writing by the non-designating party. Neither party
shall unreasonably withhold such approval. Each party shall have the right to
change its representation on the Development Committee upon written notice sent
to the other.

         4.4      Development Committee Meetings. It is anticipated that the
Development Committee shall meet not less than three (3) times a year during the
term of this Agreement, at such dates, times and locations as agreed to by the
parties. At such meetings, the Committee shall discuss the Development
Collaboration Program, the status of performance under the Development
Collaboration Plan, evaluate the results thereof and set priorities therefore.
Prior to each such meeting, each party shall prepare and deliver to the other
party written progress reports, which shall include, but not be limited to,
descriptions of the conduct of the Development Collaboration Program, including
protocols and results obtained, and such other information as the Committee
shall reasonably request. The content of all Committee meetings and reports
submitted to the Committee are hereby deemed Confidential Information subject to
both the nondisclosure and use restrictions of Article 5 herein and the
exceptions of Article 5 herein. The Committee shall be responsible

                                       12
<PAGE>

for preparing written minutes of each Committee meeting, and a written record of
all decisions made by the Committee whether made at a formal meeting or not.

         4.5      Compliance with GLP and GMP. INX and WLV shall comply with all
applicable good laboratory, clinical and manufacturing practices as determined
by the Development Committee, in the performance of the Development
Collaboration Plan and shall cause their Affiliates and subcontractors to do the
same.

         4.6      Subcontracts. INX may subcontract portions of the Development
Collaboration Program to be performed by it in the normal course of its
business. Any such subcontracting shall be made on the following terms:

                  (a)      the subcontracted party shall enter into a
confidentiality agreement with the subcontracting party consistent with Article
5 below;

                  (b)      the subcontracted party shall be in compliance in all
material respects with all requirements of applicable laws and regulations and
this Agreement, together with all applicable good laboratory practices and good
manufacturing practices; and

                  (c)      the subcontracting party shall guarantee the
performance of the work to be performed by the subcontracted party.

ARTICLE 5 - CONFIDENTIALITY

         5.1      Confidentiality Agreement. Under the August 1, 1999
Confidentiality Agreement, INX and WLV have exchanged certain information in
order for INX and WLV to prepare an initial Development Collaboration Plan. The
parties hereby acknowledge that this License and Development Collaboration
Agreement constitutes the agreement by the parties establishing the more
extensive collaboration and agree that this License and Development
Collaboration Agreement shall govern the disposition of all information, data
and materials resulting from or arising out of the work performed by each party
under the Confidentiality Agreement and that ownership of such information, data
and materials shall be determined as provided in Article 7 hereof. INX and WLV
hereby agree that the Confidentiality Agreement is terminated and superceded
upon execution of this Agreement.

         5.2      Confidential Information and Materials. During the term of the
Development Collaboration Program, INX and WLV shall (i) exchange all
information developed pursuant to the Development Collaboration Program,
including all Inventions, INX Know-How and INX Patent Rights relating to the
Field which include data or ideas conceived by employees or consultants of
either Party since the date of the August 12, 1999 Confidentiality Agreement,
and (ii) provide all biological materials owned and transferable by each party
as necessary or useful for each party to perform its role in the Development
Collaboration Program as described in the Development Collaboration Plan. All
such information and materials when supplied pursuant to this Section 5.2 shall
be

                                       13
<PAGE>

deemed to be Confidential Information, as such term is defined in Article 5, and
shall be used only as permitted by Article 5 hereof.

         5.3      Nondisclosure Obligations. Except as otherwise provided in
this Article 5:

                  (a)      during the term of this Agreement and for a period of
three (3) years thereafter (but not less than five (5) years after the Effective
Date), each party shall maintain in confidence, and use only for purposes of
this Agreement, information and data resulting from or related to the
Development Collaboration or information pertaining to the activities of either
party regarding the research, development, manufacture, marketing, and sales of
Licensed Products; and

                  (b)      during the term of this Agreement and for a period of
three (3) years thereafter (but not less than five (5) years after the Effective
Date), both parties shall also maintain in confidence and use only for purposes
of this Agreement all information and data not described in clause (a) above but
supplied by the other party under this Agreement marked "Confidential." Within
thirty (30) days following an oral disclosure, the disclosing party shall
provide a written summary of the oral disclosure indicating with reasonable
specificity which portions are to be treated as Confidential. "Confidential
Information" shall mean information and data described in clause (a) or (b)
above.

         5.4      Permitted Disclosures. To the extent it is reasonably
necessary or appropriate to fulfill its obligations or exercise its rights under
this Agreement,

                  (a) a party may disclose to a Person Confidential Information
it is otherwise obligated under this Article 5 not to disclose to its
Affiliates, sublicensees, consultants, outside contractors and clinical
investigators, on a need-to-know basis, provided that such Person agrees to keep
the Confidential Information confidential and not use the Confidential
Information for the same time periods and to the same extent as such party is
required and that the disclosing party shall provide written notice to the other
party and sufficient opportunity to object to such disclosure; and

                  (b) a party may disclose such Confidential Information to
government or other regulatory authorities to the extent that such disclosure is
required by applicable law, regulation or court order, or is reasonably
necessary to obtain patents or authorizations to conduct clinical trials, and to
commercially market a Licensed Product, provided that the disclosing party
shall, to the extent reasonably possible, provide written notice to the other
party and sufficient opportunity to object to such disclosure or to request
confidential treatment thereof, and the party shall take reasonable steps to
limit the scope of such disclosure, subject to review by the disclosing party;
and

                  (c) the parties may agree to publish or present at scientific
conferences the results of ongoing work under the Development Collaboration
Program or data otherwise related to research and development of Licensed
Products, as set forth below in Article 6.

         5.5      Additional Permitted Disclosures. The obligation not to
disclose or use Confidential Information shall not apply to any part of such
Confidential Information that (i) is or becomes patented, published or otherwise
part of the public domain other than by acts of the party obligated not to
disclose such Confidential Information or its Affiliates in contravention of
this Agreement; (ii) is disclosed to the receiving party or its Affiliates by a

                                       14
<PAGE>

Third Party who has a lawful right to make the disclosure; (iii) prior to
disclosure under this Agreement, was already in the possession of the receiving
party or its Affiliates as established by written records, provided such
Confidential Information was not obtained from the other party under this
Agreement or the Confidentiality Agreement on a confidential basis; or (iv) is
disclosed in a press release mutually agreed to in writing by both parties
hereto, which agreement shall not be unreasonably withheld.

         5.6      Terms of this Agreement. The parties shall not disclose any
terms or conditions of this Agreement to any Third Party without the prior
consent of the other party, except:

                  (a)      to Persons with whom a party has entered into or
proposes to enter into a business relationship, provided that such Persons shall
enter into the required confidentiality agreement, or

                  (b)      as required by applicable law, regulation or court
order, provided that, to the extent reasonably possible, the disclosing party
shall provide written notice to the other party and sufficient opportunity to
review and/or to object to such disclosure or to request confidential treatment
thereof, and the party shall take reasonable steps to limit the scope of such
disclosure, subject to review by the disclosing party.

         Notwithstanding the foregoing, prior to execution of this Agreement,
WLV and INX shall agree upon the substance of information that can be used to
describe the terms of this transaction, and WLV and INX may disclose such
information, as modified by mutual written agreement from time to time, without
the other party's consent.

         5.7      Transfer of Materials. In the performance of the Development
Collaboration Plan either party (the "Supplier") may provide biological
materials, reagents or other materials ("Material") to the other party (the
"Recipient").

                  (a)      Transferred Material is the sole property of the
Supplier and is made available to the Recipient for the sole purpose of the
Development Collaboration Plan. The transfer of Material does not transfer
ownership of the Material to the Recipient. Recipient agrees to return all
unused Material at the conclusion of the authorized activity and further agrees
not to use the Material for any unauthorized purposes.

                  (b)      EACH RECIPIENT ACKNOWLEDGES THAT ANY MATERIALS
DELIVERED TO IT UNDER THIS AGREEMENT ARE EXPERIMENTAL IN NATURE. EACH SUPPLIER
MAKES NO REPRESENTATIONS AND EXTENDS NO WARRANTIES OF ANY KIND, EITHER EXPRESS
OR IMPLIED, WITH RESPECT TO THE MATERIALS. THERE ARE NO EXPRESS OR IMPLIED
WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. THE SUPPLY OF
MATERIAL IS NOT A REPRESENTATION THAT USE OF THE MATERIALS WILL NOT INFRINGE ANY
PATENT, COPYRIGHT, TRADE SECRET, TRADEMARK OR OTHER RIGHTS OF THIRD PARTIES.

                  (c)      each Recipient assumes all liability for damages
which may arise from the Recipient's use, storage, disposal or transfer of the
Materials. Supplier shall not be liable to the Recipient for any loss, claim, or
demand made by the Recipient, or made

                                       15
<PAGE>

against the Recipient by any other party, due to or arising from the use or
transfer of the Material by the Recipient, except when caused solely by the
gross negligence or improper intentional acts of the Supplier. The Material is
to be used only by a qualified investigator and will not be administered to a
human.

ARTICLE 6 - PUBLICATION

         6.1      Notice of Publication. During the term of this Agreement, INX
and WLV each acknowledge the other party's interest in publishing certain of its
results to obtain recognition within the scientific community and to advance the
state of scientific knowledge. Each party also recognizes the mutual interest in
obtaining valid patent protection and protecting business interests.
Consequently, either party, its employees or consultants wishing to make a
publication (including any oral disclosure, and written abstracts thereof
submitted for publication, made without obligation of confidentiality) relating
to work performed by such party as part of the Development Collaboration Program
(the "Publishing Party") shall transmit to the other party (the "Reviewing
Party") a copy of the proposed written publication at least thirty (30) days
prior to submission for publication, or an outline of such oral disclosure,
including abstracts thereof, at least thirty (30) days prior to presentation.
The Reviewing Party shall have the right

                  (a)      to propose reasonable modifications to the
publication for patent or other commercial reasons,

                  (b)      to request a reasonable delay in publication in order
to protect patentable information, and

                  (c)      to prohibit such publication in order to protect
Confidential Information, including patentable information or trade secret
information, consistent with the confidentiality obligations of Article 5 above.

ARTICLE 7 - INVENTIONS AND PATENTS

         7.1      Ownership Of Inventions. Ownership of Inventions shall be
determined by inventorship, which in turn shall be determined in accordance with
U.S. patent law. The entire right and title in all INX Inventions, and any
patent applications or patents based thereon, shall be owned solely by INX. The
entire right and title in all Inventions made by WLV, and any patent
applications or patents based thereon, shall be owned solely by WLV. The entire
right and title in all Joint Patent Rights and Joint Inventions, and any patent
applications or patents based thereon, shall be owned jointly by WLV and INX.

         7.2      Disclosure of Inventions. Each party promptly shall disclose
to the other party the making, conception or reduction to practice of Inventions
by employees or others acting on behalf of such party in the performance of the
Development Collaboration Plan. INX and WLV each hereby represent that all
employees and other Persons acting on its behalf in performing its obligations
under this Agreement shall be obligated under a binding written agreement to
assign to it, or as it shall direct, all Inventions made or developed by such
employees or other Persons.

                                       16
<PAGE>

         7.3      Grant-back to WLV Inventions. In the event that an Invention
made by WLV, utilizing INX Confidential Information or Know-How, represents an
improvement to the MSCRAMM technology of INX, then WLV shall grant to INX a
nonrevocable, fully paid-up nonexclusive license, with ability to sublicense, to
any patent rights of WLV regarding such Invention, in all fields other than the
Field of this Agreement. WLV shall also grant to INX an exclusive option to
negotiate the terms of an exclusive license to such Invention, such option to
expire six (6) months from the date of disclosure to INX of the Invention.

         7.4      Option Rights to INX Inventions. INX shall grant to WLV an
exclusive option to negotiate the terms of a nonexclusive or exclusive license,
at WLV's election, to any patent rights of INX regarding INX Inventions or INX
ownership interest in Joint Inventions, outside the Field of this Agreement to
the extent it does not involve the stimulation of antibody titer in plasma
donors whose plasma is collected for the purpose of developing and
commercializing products containing plasma derived immunoglobulin. Such
exclusive option shall expire three (3) months from the date of disclosure of
such INX Invention to WLV.

         7.5      Cooperation Outside the Field. During the term of this
Agreement and prior to regulatory approval of a Licensed Product, if INX desires
to use the licensed Product to stimulate antibody titer in plasma donors whose
plasma is collected for the purpose of developing and commercializing products
containing plasma derived immunoglobulin then WLV will cooperate with INX, to
the extent it is commercially feasible and does not hinder the efforts of WLV to
commercialize or market Licensed Products in the Field.

         7.6      Patent Prosecution and Maintenance.

         (a)      INX shall be responsible for and shall control the
preparation, filing, prosecution, grant and maintenance (collectively "Patent
Management") of all INX Patent Rights, using patent counsel reasonably
acceptable to WLV. Whenever reasonably feasible INX shall consult with WLV as to
the preparation, filing, prosecution, and maintenance of all INX Patent Rights
reasonably prior to any deadline or action with the United States Patent &
Trademark Office or any foreign patent office and whenever reasonably feasible
shall furnish WLV with drafts of relevant documents reasonably in advance of
consultation. WLV shall have the right to review and comment on such patent
applications and prosecution documents prior to filing in the United States and
abroad. INX and WLV agree to cooperate with each other during the patent
application and prosecution process by executing papers and providing
assistance, data, information, and research records. INX and WLV also agree to
cooperate in the event the extension of any patent term is sought under 35
U.S.C. 156 (Patent Term Restoration). These cooperation provisions shall survive
the termination or expiration of this Agreement. Failure of INX to afford WLV
prior consultation and review of documents shall not constitute material breach
of this Agreement.

         (b)      WLV shall reimburse INX for fifty percent (50%) of its
expenses incurred

                                       17
<PAGE>

after the Effective Date in connection with such Patent Management of INX Patent
Rights. In the event that WLV elects not to reimburse INX for expenses
associated with filing, prosecuting or maintaining a given patent application or
patent in a particular country, then such patent application or patent in that
country only shall not be part of the INX Patents Rights and no license is
granted to WLV under such patent application or patent in that country pursuant
to this Agreement.

         (c)      if INX elects not to file for patent protection in a
particular country including the United States, or if INX elects not to continue
with the prosecution or maintenance of a given patent or patent application or
claim within an application, then WLV may request that INX proceed and INX
hereby agrees to do so. One hundred percent (100%) of expenses incurred by INX
in connection with proceeding in accordance with such request shall be
reimbursed by WLV and the patent will be owned by INX and licensed to WLV under
this agreement.

         (d)      at its own expense WLV shall be responsible for and shall
control the preparation, filing, prosecution, grant and maintenance of all
applications regarding WLV Inventions.

         (e)      the parties shall determine the most appropriate method for
the preparation, filing, prosecution, grant, and maintenance of Joint Inventions
and Joint Patent Rights, and the parties shall equally share the expenses.

         7.7      Prior Art. Each party shall cooperate with the other to the
extent reasonably possible to ensure that all known prior art that is material
to the examination of a Joint Patent Right is brought to the attention of the
other party and the U.S. Patent and Trademark Office.

         7.8      Enforcement of Patent Rights. Upon learning of any Third Party
infringement or threatened infringement of any Patent Right in the Field, INX or
WLV, as the case may be, promptly shall provide notice to the other party in
writing of the fact and shall supply the other party with all evidence possessed
by the notifying party pertaining to and establishing such infringement. Each
party shall provide to the other any facts which may affect the validity, scope
or enforceability of any Patent Right of which either party becomes aware. INX
shall have the right, at its expense, to determine the appropriate course of
action to enforce its Patent Rights or otherwise abate the infringement thereof,
to determine whether to take (or refrain from taking) appropriate action to
enforce its Patent Rights, and to control any litigation or other enforcement
action and to enter into, or permit, the settlement of any such litigation or
other enforcement action, and retain any damages or recovery in any such action
with respect to its Patent Rights, and in good faith the party controlling such
litigation shall consider the interests of the other party, if any, in so doing.
In the event the INX elects in writing not to take action to enforce its Patent
Rights, WLV may do so at its own expense controlling the litigation and
retaining any damages or recovery (less any royalties owed on damages won as a
result of lost sales), provided that no patent claims outside the Field are put
at issue in such litigation and further provided that INX may participate in
such litigation at it own expense. WLV shall

                                       18
<PAGE>

take no action to compel INX either to initiate or to join in any such suit for
patent infringement. At WLV's request, INX shall initiate or join in any such
suit if necessary to avoid dismissal of the suit; in such event, WLV shall
reimburse INX for its reasonable attorney's fees and costs.

         7.9      Defense of Declaratory Judgment Actions. In the event that a
declaratory judgment action alleging invalidity or non-infringement of any of
the Patent Rights shall be brought against WLV or raised by way of counterclaim
or affirmative defense in an infringement suit brought by WLV under Paragraph
7.8, WLV may: (a) defend the suit in its own name, at its own expense, and on
its own behalf for presumably Valid Claims in the Patent Rights in the Field
provided that no claims outside the Field are put at issue in such litigation;
(b) in any such suit, ultimately enjoin infringement and collect for its use,
damages, profits, and awards of whatever nature recoverable for such
infringement; and (c) settle any claim or suit for declaratory judgment
involving the Patent Rights and collect for its use all monies recovered from
such settlement; provided, however, that INX shall have the first right to take
such actions and shall have a continuing right to intervene in such suit,
subject to WLV's right to control the defense of such suit. If INX does not
notify WLV of its intent to respond to the legal action within a reasonable
time, WLV will be free to do so. WLV shall take no action to compel INX to join
in any such declaratory judgment action; however, if INX is deemed to be a
necessary party to such suit, WLV shall reimburse INX for its reasonable
attorney's fees and costs.

         7.10     Enforcement of Joint Patent Rights. The parties shall
determine the appropriate course of action to enforce the Joint Patent Rights or
otherwise abate the infringement thereof, to determine whether to take (or
refrain from taking) appropriate action to enforce such Joint Patent Rights, and
shall determine, on a case by case basis, which party should control any
litigation or other enforcement action and to enter into, or permit, the
settlement of any such litigation or other enforcement action with respect to
the Joint Patent Rights, and in good faith the party controlling such litigation
shall consult with the other party and shall consider the interests of the other
party, if any, in so doing. If a party elects to enforce Joint Patent Rights by
itself it may do so at its own expense and retain for itself all damages or
recovery in such action. The parties may agree to jointly enforce Joint Patent
Rights, share costs and expenses, and share in any damages or recovery.

         7.11     Defense of Infringement Suits Against WLV. WLV shall promptly
notify INX in writing of any allegation, claim or suit by a Third Party that the
activity of WLV in connection with the performance of this Agreement infringes
or may infringe the intellectual property rights of such Third Party. WLV shall
have full control of the defense and resolution of such allegation, claim or
suit. Such control shall include negotiations with the Third Party, selection
and supervision of counsel, defense of suits (or the filing of a declaratory
judgment action by WLV) or other proceedings, and settlement of such allegation,
claim or suit, which may include WLV's taking a license from said Third Party.
All costs and expenses, including attorney's fees, incurred in the course of
resolving such allegation, claim or suit shall be the responsibility of WLV. In
the event that WLV is permanently enjoined from making, using or selling a
Licensed Product in a given

                                       19
<PAGE>

jurisdiction, then that injunction shall not constitute a breach of WLV's
obligations under Section 2.14 and shall not constitute a basis for termination
by INX of this Agreement under Section 8.1.3.

ARTICLE 8 - TERM AND TERMINATION

         8.0      Term. The term of this Agreement shall be from the last
signature date below until the expiration of all INX Patent Rights

         8.1      Termination For Cause. Either party may terminate this
Agreement and the license granted herein, at its option, upon the occurrence of
any of the following:

         8.1.1    The other party:

                  (a)      seeks the liquidation, reorganization, dissolution or
winding up of itself (other than dissolution or winding up for the purposes of
reconstruction or amalgamation),

                  (b)      applies for or consent to the appointment of, or the
taking of possession by, a receiver, custodian, trustee or liquidator of itself
or of all or substantially all of its assets,

                  (c)      makes a general assignment for the benefit of its
creditors,

                  (d)      commences a voluntary case under the Bankruptcy Code,

                  (e)      files a petition seeking to take advantage of any
other law relating to bankruptcy, insolvency, reorganization, winding-up or
composition or readjustment of debts, or

                  (f)      adopt any resolution of its Board of Directors or
stockholders for the purpose of effecting any of the foregoing; or

         8.1.2    A proceeding or case shall be commenced without the
application or consent of the other party and such proceeding or case shall
continues undismissed, or an order, judgment or decree approving or ordering any
of the following is entered and continues unstayed in effect, for a period of
ninety (90) days from and after the date service of process is effected upon the
other party, seeking

                  (a)      its liquidation, reorganization, dissolution or
winding up, or the composition or readjustment of all or substantially all of
its debts,

                  (b)      the appointment of a trustee, receiver, custodian,
liquidator or the like of itself or of all or substantially all of its assets,
or

                  (c)      similar relief under any law relating to bankruptcy,
insolvency, reorganization, winding up or composition or readjustment of debts;
or

         8.1.3    Upon or after the material breach of any material provision of
this Agreement, if the breaching party has not cured such breach within sixty
(60) days after notice thereof from the other party. Failure to make any
payments due within the sixty (60) day period shall be a material breach of a
material provision of this Agreement.

         8.2      Termination Without Cause. WLV may terminate this Agreement at
any time without cause upon (a) six months written notice, and (b) upon payment
of any

                                       20
<PAGE>

balance due for the full annual license and development support fee for the
calendar year in which such six month notice period expires, and (c) upon
payment of any support fees in excess of [ *** ] budgeted in the Development
Collaboration Plan for the calendar year in which such six month notice period
expires.

         8.3      Effect of Expiration and Termination. Expiration or
termination of this Agreement shall not relieve the parties of any obligation
accruing prior to such expiration or termination. The provisions of Articles 3,
5, 6, Sections 7.1, 7.2, 7.3 and 7.10 of Article 7 and Article 9 shall survive
the expiration or termination of this Agreement. Upon termination WLV shall, at
the election of INX, either sell or destroy any Licensed Product not sold as of
the termination date. The royalty provided herein shall be paid on any permitted
post-termination sales.

         8.4      Survival of Sublicenses. Upon termination of this Agreement
without cause, no existing sublicenses granted by WLV shall be affected by such
termination, and all such sublicenses shall remain in effect according to their
terms and shall be converted to direct sublicenses (to a sole exclusive
sublicense if there is only one sublicensee, or to co-exclusive sublicenses if
there are two or more sublicensees). INX shall continue to be entitled to
payments under such sublicenses pursuant to Article 2 above.

ARTICLE 9 - INDEMNIFICATION

         9.1      Indemnity. Each party shall indemnify and hold harmless, and
hereby forever releases and discharges, the other party, its successors,
Affiliates and sublicensees, from and against all claims, demands, liabilities,
damages and expenses, including reasonable attorneys' fees and costs
(collectively "Liabilities") arising directly out of

                  (a)      the breach of any material provision of this
Agreement by the indemnifying party, or

                  (b)      the negligence, recklessness or intentional acts or
omissions of the indemnifying party in complying with its obligations under this
Agreement.

         9.2      WLV Indemnification WLV hereby indemnifies and agrees to
defend and to hold INX, its successors and Affiliates, and any licensors of INX
harmless from and against all claims, Liabilities, losses and expenses
(collectively "Losses") arising out of or in connection with WLV's manufacture,
use, lease, import or sale of Licensed Product. This indemnification shall not
extend to Losses due to the negligent or willful misconduct of INX, its
successors or Affiliates.

         9.3      Procedure. A party (the "Indemnitee") that intends to claim
indemnification under this Article 9 shall promptly notify the other party (the
"Indemnitor") of any Liability or action in respect of which the Indemnitee
intends to claim such indemnification, and the Indemnitor shall have the right
to participate in, and, to the extent the Indemnitor so desires, jointly with
any other Indemnitor similarly noticed, to assume the defense thereof with
counsel selected by the Indemnitor; provided, however, that an Indemnitee shall
have the right to retain its own counsel, with the fees and expenses to be paid
by the Indemnitor,

                                       21
<PAGE>

if representation of such Indemnitee by the counsel retained by the Indemnitor
would be inappropriate due to actual or potential differing interests between
such Indemnitee and any other party represented by such counsel in such
proceedings. The indemnity obligations under this Article 9 shall not apply to
amounts paid in settlement of any loss, claim, damage, liability or action if
such settlement is effected without the consent of the Indemnitor, which consent
shall not be unreasonably withheld. The failure to deliver notice to the
Indemnitor within a reasonable time after the commencement of any such action,
if prejudicial to its ability to defend such action, shall relieve such
Indemnitor of any liability to the Indemnitee under this Article 9, but the
omission to so deliver notice to the Indemnitor will not relieve it of any
liability that it may have to any Indemnitee otherwise than under this Article
9. The Indemnitee, its employees and agents, shall cooperate fully with the
Indemnitor and its legal representatives in the investigation of any action,
claim or liability covered by this indemnification.

ARTICLE 10 - BREACH

         10.1     Breach. In the event that either party is in material breach
of any of its obligations, representations or warranties under this Agreement
which remains uncured sixty (60) days following written notice of such breach,
then in addition to any other rights or remedies set forth herein or provided by
law, the breaching party shall be liable to the nonbreaching party for actual
damages (including reasonable attorneys' fees) incurred by the nonbreaching
party directly as a result of the material breach.

ARTICLE 11 - FORCE MAJEURE

         11.1     Force Majeure. Neither party shall be held liable or
responsible to the other party nor be deemed to have defaulted under or breached
this Agreement for failure or delay in fulfilling or performing any term of this
Agreement when such failure or delay is caused by or results from causes beyond
the reasonable control of the affected party (hereinafter, A Force Majeure
event). For purposes of this Agreement, a Force Majeure event includes, but is
not limited to, earthquake, fire, floods, embargoes, war, acts of war (whether
war be declared or not), insurrections, riots, civil commotions, strikes,
lockouts or other labor disturbances, acts of God or acts, omissions or delays
in acting by any governmental authority (including regulatory and advisory
bodies) or the other party. Upon the occurrence of any Force Majeure event, the
affected party shall give written notice of such event to the other party and
shall use reasonable efforts to

overcome such Force Majeure event. Performance, however, shall not be excused
for a period greater than six (6) months. Performance shall not be excused where
failure to perform results from failure to comply with FDA rules and
regulations.

ARTICLE 12 - ASSIGNMENT

                                       22
<PAGE>

         12.1     Assignment. This Agreement may not be assigned or otherwise
transferred, nor, except as expressly provided hereunder, may any right or
obligations hereunder be assigned or transferred by either party without the
consent of the other party, which consent shall not be unreasonably withheld.
Either party may, however, without such consent, assign this Agreement and its
rights and delegate its obligations hereunder to an Affiliate or in connection
with the transfer or sale of all or substantially all of its business relating
to this Agreement, including, but not limited to, assignment to an Affiliate, or
in the event of its merger or consolidation or change in control or similar
transaction. Any permitted assignee shall assume in writing all obligations of
its assignor under this Agreement.

ARTICLE 13 - SEVERABILITY

         13.1     Severability. Each party hereby agrees that it does not intend
to violate any public policy, statutory or common laws, rules, regulations,
treaty or decision of any government agency or executive body thereof of any
country or co-unity or association of countries. Should one or more provisions
of this Agreement be or become invalid, the parties hereto shall substitute, by
mutual consent, valid provisions for such invalid provisions which valid
provisions in their economic effect are sufficiently similar to the invalid
provisions that it can be reasonably assumed that the parties would have entered
into this Agreement with such provisions. In case such provisions cannot be
agreed upon, the invalidity of one or several provisions of this Agreement shall
not affect the validity of this Agreement as a whole, unless the invalid
provisions are of such essential importance to this Agreement that it is to be
reasonably assumed that the parties would not have entered into this Agreement
without the invalid provisions.

ARTICLE 14 - MISCELLANEOUS

         14.1     Notices. Any consent, notice or report required or permitted
to be given or made under this Agreement by one of the parties hereto to the
other shall be in writing, delivered personally, or by facsimile and promptly
confirmed by personal delivery, U.S. first class mail or courier, postage
prepaid (where applicable), addressed to such other party at its address
indicated below, or to such other address as the addressee shall have last
furnished in writing to the addressor and (except as otherwise provided in this
Agreement) shall be effective upon receipt by the addressee. A party may change
its address by giving written notice to the other party.

If to Inhibitex, Inc.:
Inhibitex, Inc.
8995 Westside Parkway, Suite 150
Alpharetta, GA 30004
Attention: President
Telefax: 678 336 2612

                                       23
<PAGE>

If to WLV:

Notices only:                           All other communications, invoices and
                                        payments:
WLV-Lederle Vaccines                    WLV-Lederle Vaccines
c/o Wyeth-Ayerst Laboratories           401 North Middletown Road
280 King of Prussia Road                Pearl River, NY 10965
Radnor, PA 19087                        Attention: Director, Technology Affairs
Attention: President                    Telefax: (845) 732-2825
Telefax: 610-989-5700

         14.2     Applicable Law. This Agreement is deemed to have been executed
in and shall be governed by and construed in accordance with the laws of the
State of Georgia, except for questions regarding patents, which shall be
resolved in the courts having jurisdiction over the patents in question and in
accordance with the laws applicable to such patents.

         14.3     Dispute Resolution. The parties agree that in the event a
business or technical dispute arises under this Agreement, they will attempt to
resolve such disputes through their negotiations before pursuing litigation Both
parties hereby commit themselves to use the negotiating and problem solving
talents of their business or technical people, as appropriate, to work toward a
pragmatic resolution of the dispute

         14.4     Export Control. WLV shall be responsible for compliance with
the United States Export Administration Act of 1979, as amended, the Federal
Food, Drug and Cosmetic Act, and other applicable export and re-export laws,
their rules and regulations with respect to the export from the United States
and re-export of any technology or Licensed Products developed under this
Agreement. INX shall provide reasonable assistance to WLV as necessary in any
actions associated with such compliance, including obtaining any applicable
validated or general license from the United States Department Of Commerce, the
United States Food and Drug Administration or any other agency or department of
the United States Government, as required.

         14.5     Entire Agreement. This Agreement (together with Exhibits A, B
and C) constitutes the entire understanding of the parties with respect to the
subject matter hereof. All express or implied agreements and understandings,
either oral or written, heretofore made are expressly superseded by this
Agreement. This Agreement may be amended, or any term hereof modified, only by a
written instrument duly executed by both parties hereto.

         14.6     Headings. The captions to the several Articles and Sections
hereof are not a part of this Agreement, but are merely guides or labels to
assist in locating and reading the several Articles and Sections hereof.

         14.7     Independent Contractors. INX and WLV each acknowledge that
they shall be independent contractors and that the relationship between the two
parties shall not

                                       24
<PAGE>

constitute a partnership, joint venture or agency. Neither INX nor WLV shall
have the authority to make any statements, representations or commitments of any
kind, or to take any action, which shall be binding on the other party, without
the prior written consent of the other party to do so.

         14.8     Waiver. The waiver by either party hereto of any right
hereunder or the failure to perform or of a breach by the other party shall not
be deemed a waiver of any other right hereunder or of any other breach or
failure by said other party whether of a similar nature or otherwise.

         14.9     Hart-Scott-Rodino Filings. The parties will prepare and make
appropriate filings under Title II of the Hart-Scott-Rodino Antitrust
Improvements Act of 1976, as amended, and the rules promulgated thereunder (16
C.F.R. 801.1 et seq.) ("the Act") as soon as reasonably practicable. The parties
agree to cooperate in the antitrust clearance process and to furnish promptly to
the Federal Trade Commission and the Antitrust Division of the Department of
Justice any additional information reasonably requested by them in connection
with such filings. This Agreement shall bind the parties upon execution, but the
other provisions of this Agreement shall not become effective until the earlier
of (a) the waiting period provided by the Act shall have terminated or shall
have expired without any action by any government agency or challenge to the
termination, or (b) a determination has been made by WLV that a filing under the
Act is not necessary. In the event the expiration of the waiting period does not
occur within four (4) months after the Effective Date, the parties shall revert
to their status prior to signing this Agreement.

IN WITNESS WHEREOF, the parties have executed this Agreement to be effective as
of the Effective Date.

INHIBITEX, INC.

By:  /s/ Robert Schweiger
   ---------------------------------------
         Robert Schweiger

Title:   VP Business Development
Date:    8/2/01

AMERICAN HOME PRODUCTS CORPORATION
Wyeth-Ayerst Laboratories Division

By:  [ILLEGIBLE]
   ---------------------------------------
Title: President, Wyeth Vaccines and Nutrition
Date: 7/31/01

                                       25
<PAGE>

                                    EXHIBIT A

                      SPECIAL DEVELOPMENT PAYMENT SCHEDULE

<TABLE>
<CAPTION>
                                   Single          Second Single     Initial Multi-
                               Staphylococcal     Staphylococcal     Staphylococcal
Development                        Target             Target             Target
Achievement                        Vaccine            Vaccine            Vaccine
-----------------------------------------------------------------------------------
<S>                            <C>                <C>                <C>
Filing an IND                      [ *** ]           [ *** ]            [ *** ]
-----------------------------------------------------------------------------------
Entry into Phase II                [ *** ]           [ *** ]            [ *** ]
-----------------------------------------------------------------------------------
Entry into Phase III               [ *** ]           [ *** ]            [ *** ]
-----------------------------------------------------------------------------------
BLA filing                         [ *** ]           [ *** ]            [ *** ]
-----------------------------------------------------------------------------------
Licensed Product Approval          [ *** ]           [ *** ]            [ *** ]
-----------------------------------------------------------------------------------
</TABLE>

Special Development Explanation

The term Single Staphylococcal Target Vaccine refers to a vaccine addressing
either S. aureus or S. epidermidis, but not both. A Single Staphylococcal Target
Vaccine may involve multiple antigens and would not constitute a special
development payment requirement under the Second Single Staphylococcal Target
Vaccine.

Development Payments for the Initial Multi-Staphylococcal Target Vaccine would
only be triggered at any given level if that specific special development
achievement was first reached with a combination of S. aureus and S. epidermidis
vaccine.

As an illustration, if an IND and Phase II trial were initiated for a S. aureus
vaccine based on one or more antigens, special development payments of [ *** ]
would be payable at the IND filing and [ *** ] at the Entry into Phase II
trials. If, on a parallel basis similar trials for a S. epidermidis vaccine were
initiated, [ *** ] would be payable at the IND filing and [ *** ] at the Entry
into Phase II trials. If then the two vaccines were combined into a single Phase
III trial, a [ *** ] special development payment would be made payable upon
entry into that trial.

The maximum combined special development payments payable will not exceed
[ *** ].

                                       26
<PAGE>

                                    EXHIBIT B

                                INX PATENT RIGHTS

1.       "Polypeptides and Polynucleotides From Coagulase-Negative
         Staphylococci" U.S. provisional application 60/098,443 filed 8-31-98
         and refiled to add additional subject matter as 60/117,119 on 1-25-99.
         These provisional applications were converted to U.S. application
         09/386,962 filed August 31, 1999, and filed as PCT/US99/19728.
         (Licensed exclusively to INX by The Texas A&M University System (TAMUS)
         and BioResearch Ireland (BRI). TAMUS and BRI reserve the right to use
         this technology for noncommercial research and educational purposes.
         The U.S. Government holds certain rights under 37 CFR 410.14. No
         license is granted under any service mark or trademark of TAMUS. The
         name of TAMUS may not be used by WLV except to state that it is a
         sublicensee of TAMUS).

2.       "Multicomponent Vaccines"

         U.S. provisional Application 60/098,439 filed 8-31-98. This was
         converted to U.S. application 09/386,959 and PCT/US99/19727 on August
         31, 1999. (Licensed exclusively to INX by The Texas A&M University
         System (TAMUS) and Bioresearch Ireland (BRI). TAMUS and BRI reserve the
         right to use this technology for noncommercial research and educational
         purposes. The U.S. Government holds certain rights under 37 CFR 410.14.
         No license is granted under any service mark or trademark of TAMUS. The
         name of TAMUS may not be used by WLV except to state that it is a
         sublicensee of TAMUS).

3.       "Fibrinogen Binding Proteins From Staphylococcus aureus"

         U.S. provisional application filed 11-26-97 as 60/066,815 abandoned in
         favor of "Extracellular Matrix-Binding Proteins From Staphylococcus
         aureus to add additional information, filed 8-31-98 as 60/098,427
         converted 11-25-98 to 09/200,650. PCT /US98/25246 was filed 11-25-98.
         (Licensed exclusively to INX by The Texas A&M University System (TAMUS)
         and BioResearch Ireland (BRI). TAMUS and BRI reserve the right to use
         this technology for noncommercial research and educational purposes.
         The U.S. Government holds certain rights under 37 CFR 410.14. No
         license is granted under any service mark or trademark of TAMUS. The
         name of TAMUS may not be used by WLV except to state that it is a
         sublicensee of TAMUS).

4.       "Fibronectin Binding Protein Compositions and Methods of Use"

                                       27
<PAGE>

         U.S. provisional application filed 1-21-97 as 60/036,139, converted
         1-21-98 to 09/010,317; PCT filed 1-21-98 as PCT/US98/01222. (Licensed
         exclusively from TAMUS through the AM Fund I to INX. TAMUS reserves the
         right to use this technology for noncommercial research and education
         purposes. . The U.S. Government holds certain rights under 37 CFR
         410.14. No license is granted under any service mark or trademark of
         TAMUS. The name of TAMUS may not be used by WLV except to state that it
         is a sublicensee of TAMUS.)

5.       "Collagen Binding Protein Compositions and Methods of Use"

         U.S. provisional application 60/017,678 filed 5-16-96 converted 5-14-97
         to 08/856,253; PCT/US97/08210 filed 5-14-97. (Licensed exclusively from
         TAMUS through the AM Fund I to INX. TAMUS reserves the right to use
         this technology for noncommercial research and education purposes. The
         U.S. Government holds certain rights under 37 CFR 410.14. No license is
         granted under any service mark or trademark of TAMUS. The name of TAMUS
         may not be used by WLV except to state that it is a sublicensee of
         TAMUS.)

6.       "S. aureus Fibrinogen Binding Protein Gene"

         U.S. application 08/293,728 filed 8-22-94, issued as U.S. patent
         6,008,341 on 12-28-99; Div. App. 09/421,868 was filed 10-19-99 and
         another divisional application was filed 10-5-00. (Licensed exclusively
         to INX by BRI. BRI reserves the right to use this technology for
         noncommercial research and educational purposes.)

7.       "MHC II Analog From Staphylococcus aureus"

         U.S. application filed 5-24-94 as 08/248,021 and issued 7-15-1997 as
         U.S. patent 5,648,240. (Licensed exclusively from TAMUS through the AM
         Fund I to INX. TAMUS reserves the right to use this technology for
         noncommercial research and education purposes. The U.S. Government
         holds certain rights under 37 CFR 410.14. No license is granted under
         any service mark or trademark of TAMUS. The name of TAMUS may not be
         used by WLV except to state that it is a sublicensee of TAMUS.)

8.       "Fibronectin Binding Peptide"

         Filings: SE 90 2617 filed 8-10-90; U.S. 846,995 filed 6-8-92 now
         abandoned; U.S. 55,783 filed 5-3-93 now abandoned, U.S. 234,622 filed
         4-28-94 issued as U.S. patent 5,440,014 on 8-8-95. (Nonexclusively from
         Magnus Hook.)

9.       "Fibronectin Binding Protein As Well As Its Preparation"

         Filings: SE 89 1687 filed 5-11-89; U.S. 520,808 parent filed 5-9-90
         issued as U.S. patent 5,175,096 on 12-29-92; U.S. divisional 974,181
         filed 11-10-92 now abandoned; U.S. continuation 340,458 filed 11-14-94
         issued as U.S. patent 5,652,217, "Fibronectin Binding Protein" on
         7-29-97; U.S. divisional 725,492 filed on 10-4-96 issued as U.S. patent
         5,840,846, "Fibronectin Binding Protein As Well As Its Preparation" on
         11-24-98. (Nonexclusively from Magnus Hook.)

10.      "Fibronectin Binding Protein As Well As Its Preparation"

                                       28
<PAGE>

         Filings: SE 87 2272 filed 6-1-87; U.S. parent 201,028 filed 6-1-88 now
         abandoned; U.S. continuation 746,087 filed 8-12-91 now abandoned; U.S.
         continuation 937,817 filed 1-22-93 issued as U.S. patent 5,320,951 on
         6-14-94; U.S. divisional 259,000 filed 6-13-94 issued as U.S. patent
         5,571,514 "Fibronectin Binding Protein As Well As Its Preparation" on
         11-5-96; U.S. divisional 729,767 filed 10-7-96 issued as U.S. patent
         5,770,702 "Fibronectin Binding Protein As Well As Its Preparation" on
         6-23-98. (Nonexclusively from Magnus Hook.)

11.      "Collagen Binding Protein As Well As Its Preparation"

         U.S. application 861,804 filed 8-21-92 now abandoned; U.S. continuation
         447,031 filed 5-22-95 issued as U.S. patent 5,851,794 on 12-22 98.
         (Nonexclusively from Magnus Hook.)

12.      "Method for Prophylactic Treatment of the Colonization of a S. aureus
         Bacterial Strain By Cell Surface Protein With Fibronectin and
         Fibrinogen Binding Ability"

         Filings: SE 8402938 filed 5-30-84; U.S. parent 840,580 filed 1-21-86,
         now abandoned; U.S. continuation 801,593 filed 12-5-91 and issued as
         U.S. Patent 5,189,015 on 2-23-93. (Nonexclusively from Magnus Hook.)

13.      "Bacterial Cell surface Protein with Fibronectin, Fibrinogen, Collagen
         and Laminin Binding Ability, Process for the Manufacture of the Protein
         and Prophylactic Treatment"

         Filings: U.S. 06/840,580 filed as PCT/SE85/00227 on 5-30-85; U.S.
         continuation 07/801,593 filed 12-5-91, now U.S. Patent 5,189,015; U.S.
         divisional 07/977,151 filed 11-16-92; U.S. continuation 08/118,697
         filed 9-10-93 and issued as U.S. Patent 5,980,908 on 11-9-99.
         (Nonexclusively from Magnus Hook.)

                                       29
<PAGE>

                                    EXHIBIT C

                         DEVELOPMENT COLLABORATION PLAN

The below outlined plan for the initial development of a S. aureus nosocomial
vaccine will take approximately 18-24 months to accomplish. Three and one
quarter (3.25) FTE's per year during this period from Inhibitex are necessary
for timely execution of the plan. Inhibitex will:

         1.       Provide Wyeth Lederle Vaccines (WLV) with approximately 100 mg
                  of each recombinant 6X HIS-tag versions of M55 (CNA);
                  Clf41/Clf33 (ClfA), MAP24 (MAP)

         2.       Make CP5/CP8 glycoconjugates with MSCRAMMs

                  a.       QC antigenicity with specific polyclonal IgG and
                           specific monoclonal antibodies

                  b.       Immunogenicity (immunize mice and rabbits to evaluate
                           titers)

                  c.       Conduct in vivo efficacy studies with mouse
                           bacteremia model (test active and passive
                           immunization strategies)

                           i.       Strain characterization with respect to
                                    MSCRAMM profile and CP type

                  d.       Conduct in vitro opsonophagocytosis assays with HL-60
                           human cell line and analogous murine cell line

         3.       Revise expression vectors of MSCRAMMs to exclude HIS tag

         4.       Provide WLV with approximately 100 mg of recombinant 6X
                  HIS-tag versions of the A domain from SdrG and SdrH (S.
                  epidermidis antigens)

         5.       Adjuvant/formulation analysis of lead vaccine candidate(s)
                  will be initiated by WLV.

                                       30