PATENT LICENSE AGREEMENT

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Exhibit 10.15

NATIONAL INSTITUTES OF HEALTH

CENTERS FOR DISEASE CONTROL

PATENT LICENSE AGREEMENT -- EXCLUSIVE

COVER PAGE

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For Office of Technology Transfer/NIH internal use only:

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Patent License Number: L-135-94

Serial Numbers of Licensed Patents: USPA SN 07/861,249

SN 08/065,618

Licensee: MediChem Research, Inc.

CRADA Number (if applicable):

Additional Remarks:

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This Patent License Agreement, hereinafter referred to as the "Agreement,"

consists of this Cover Page, an attached Agreement, a Signature Page, Appendix A

(Patent or Patent Application), Appendix B (Fields of Use and Territory),

Appendix C (Royalties), Appendix D (Modifications), and Appendix E (Benchmarks).

This Cover Page serves to identify the Parties to this Agreement:

1) The National Institutes of Health ("NIB") or the Centers for

Disease Control ("CDC"), hereinafter singly or collectively

referred to as "PES," agencies of the United States Public Health

Service within the Department of Health and Human Services

("DHHS"); and

2) The person, corporation, or institution identified above and/or on

the Signature Page, having offices at the address indicated on the

Signature Page, hereinafter referred to as "Licensee."

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PHS PATENT LICENSE AGREEMENT-EXCLUSIVE

PHS and Licensee agree as follows:

1. BACKGROUND

1.01 In the course of conducting biomedical and behavioral research,

PHS investigators made inventions that may have commercial

applicability.

1.02 By assignment of rights from PHS employees and other inventors,

DHHS, on behalf of the United States Government, owns intellectual

property rights claimed in any United States and foreign patent

applications or patents corresponding to the assigned inventions.

DHHS also owns any tangible embodiments of these inventions

actually reduced to practice by PHS.

1.03 The Assistant Secretary for Health of DHHS has delegated to PHS

the authority to enter into this Agreement for the licensing of

rights to these inventions under 35 U.S.C. Sections 200-212, the

Federal Technology Transfer Act of 1986, 15 U.S.C. Section 3710a,

and/or the regulations governing the licensing of Government-owned

inventions, 37 CFR Part 404.

1.04 PHS desires to transfer these inventions to the private sector

through commercialization licenses to facilitate the commercial

development of products and processes for public use and benefit.

1.05 Licensee desires to acquire commercialization rights to certain of

these inventions in order to develop processes, methods, or

marketable products for public use and benefit.

2. DEFINITIONS

2.01 "Licensed Patent Rights" shall mean:

a) U.S. patent applications and patents listed in Appendix A,

all divisions and continuations of these applications, all

patents issuing from such applications, divisions, and

continuations, and any reissues, reexaminations, and

extensions of all such patents;

b) to the extent that the following contain one or more claims

directed to the invention or inventions claimed in a)

above: i) continuations-in-part of a) above; ii) all

divisions and continuations of these continuations-in-part;

iii) all patents issuing from such continuations-in-part,

divisions, and continuations; and iv) any reissues,

reexaminations, and extensions of all such patents;

c) to the extent that the following contain one or more claims

directed to the invention or inventions claimed in a)

above:

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all counterpart foreign applications and patents to a) and

b) above, including those listed in Appendix A.

Licensed Patent Rights shall not include b) or c) above to

the extent that they contain one or more claims directed to

new matter which is not the subject matter of a claim in a)

above.

2.02 "Licensed Product(s)" means tangible materials which, in the

course of manufacture, use, or sale would, in the absence of this

Agreement, infringe one or more claims of the Licensed Patent

Rights that have not been held invalid or unenforceable by an

unappealed or unappealable judgement of a court of competent

jurisdiction.

2.03 "Licensed Process(es)" means processes which, in the course of

being practiced would, in the absence of this Agreement, infringe

one or more claims of the Licensed Patent Rights that have not

been held invalid or unenforceable by an unappealed or

unappealable judgment of a court of competent jurisdiction.

2.04 "Licensed Territory" means the geographical area identified in

Appendix B.

2.05 "Net Sales" means the total gross receipts for sales of Licensed

Products or practice of Licensed Processes by or on behalf of

Licensee or its sublicensees, and from leasing, renting, or

otherwise making Licensed Products available to others without

sale or other dispositions, whether invoiced or not, less returns

and allowances actually granted, packing costs, insurance costs,

freight out, taxes or excise duties imposed on the transaction (if

separately invoiced), and wholesaler and cash discounts in amounts

customary in the trade. No deductions shall be made for

commissions paid to individuals, whether they be with independent

sales agencies or regularly employed by Licensee, or sublicensees,

and on its payroll, or for the cost of collections.

2.06 "First Commercial Sale" means the initial transfer by or on behalf

of Licensee or its sublicensees of Licensed Products or the

initial practice of a Licensed Process by or on behalf of Licensee

or its sublicensees in exchange for cash or some equivalent to

which value can be assigned for the purpose of determining Net

Sales.

2.07 "Government" means the government of the United States of America.

2.08 "Licensed Fields of Use" means the fields of use identified in

Appendix B.

3. GRANT OF RIGHTS

3.01 PHS hereby grants and Licensee accepts, subject to the terms and

conditions of this Agreement, an exclusive license to Licensee

under the Licensed Patent Rights in the Licensed Territory to make

and have made, to use and have used, and to sell and have sold any

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Licensed Products in the Licensed Fields of Use and to practice

and have practiced any Licensed Processes in the Licensed Fields

of Use.

3.02 This Agreement confers no license or rights by implication,

estoppel, or otherwise under any patent applications or patents of

PHS other than Licensed Patent Rights regardless of whether such

patents are dominant or subordinate to Licensed Patent Rights.

4. SUBLICENSING

4.01 Upon written approval by PHS, which approval will not be

unreasonably withheld, Licensee may enter into sublicensing

agreements under the Licensed Patent Rights.

4.02 Licensee agrees that any sublicensee granted by it shall provide

that the obligations to PHS of Paragraphs 5.01-5.05, 8.01, 10.01,

10.02, 12.05, and 13.08-13.11 of this Agreement shall be binding

upon the sublicensee as if it were a party to this Agreement.

Licensee further agrees to attach copies of these Paragraphs to

all sublicense agreements.

4.03 Any sublicensee granted by Licensee shall provide for the

termination of the sublicense, or the conversion to a license

directly between such sublicensees and PHS, at the option of the

sublicensee, upon termination of this Agreement under Article 13.

Such conversion is subject to PHS approval and contingent upon

acceptance by the sublicensee of the remaining provisions of this

Agreement.

4.04 Licensee agrees to forward to PHS a copy of each fully executed

sublicense agreement postmarked within sixty (60) days of the

execution of such agreement.

5. STATUTORY AND PHS REQUIREMENTS AND RESERVED GOVERNMENT RIGHTS

5.01 PHS reserves on behalf of the Government an irrevocable,

nonexclusive, nontransferable, royalty-free license for the

practice of all inventions licensed under the Licensed Patent

Rights throughout the world by or on behalf of the Government and

on behalf of any foreign government or international organization

pursuant to any existing or future treaty or agreement to which

the Government is a signatory.

5.02 Licensee agrees that products used or sold in the United States

embodying Licensed Products or produced through use of Licensed

Processes shall be manufactured substantially in the United

States, unless a written waiver is obtained in advance from PHS.

5.03 Licensee acknowledges that PHS may enter into future Cooperative

Research and Development Agreements (CRADAs) under the Federal

Technology Transfer Act of 1986 that relate to the subject matter

of

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this Agreement. Licensee agrees not to unreasonably deny requests

for sublicense or cross-license rights from such future

collaborators with PHS when acquiring such derivative rights is

necessary in order to make a CRADA project feasible. Licensee may

request an opportunity to join as a party to the proposed CRADA.

5.04 DHHS has responsibility for funding basic biomedical research, for

funding medical treatment through programs such as Medicare and

Medicaid, for providing direct medical care and, more generally,

for protecting the health and safety of the public. Because of

these responsibilities, and the public investment in the research

that culminated in the Licensed Patent Rights, PHS may require

Licensee to submit documentation in confidence showing a

reasonable relationship between the pricing of a Licensed Product,

the public investment in that product, and the health and safety

needs of the public. This paragraph shall not restrict the right

of Licensee to price a Licensed Product or Licensed Process so as

to obtain a reasonable profit for its sale or use. This Paragraph

5.04 does not permit PHS to set or dictate prices for Licensed

Products or Licensed Processes.

5.05 In addition to the reserved license of Paragraph 5.01 above, PHS

reserves the right to grant nonexclusive licenses to make and to

use the inventions defined by the Licensed Patent Rights for

purposes of research involving the inventions themselves, and not

for purposes of commercial manufacture or in lieu of purchase if

the inventions are available as commercial products for research

purposes. The purpose of this research license is to encourage

basic research, whether conducted at an academic or corporate

facility. In order to safeguard the Licensed Patent Rights,

however, PHS shall consult with Licensee before granting to

commercial entities a research license or providing to them

research samples of the materials claimed in the Licensed Patent

Rights.

6. ROYALTIES AND REIMBURSEMENT

6.01 Licensee agrees to pay to PHS a noncreditable, nonrefundable

license issue royalty as set forth in Appendix C within thirty

(30) days from the date that this Agreement becomes effective.

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6.02 Licensee agrees to pay to PHS a nonrefundable minimum annual

royalty as set forth in Appendix C. The minimum annual royalty is

due and payable on January 1 of each calendar year and may be

credited against any earned royalties due for sales made in that

year. The minimum annual royalty due for the first calendar year

of this Agreement may be prorated according to the fraction of the

calendar year remaining between the Effective Date of this

Agreement and the next subsequent January 1.

6.03 Licensee agrees to pay PHS earned royalties as set forth in

Appendix C.

6.04 Licensee agrees to pay PHS benchmark royalties as set forth in

Appendix C.

6.05 A claim of a patent or patent application licensed under this

Agreement shall cease to fall within the Licensed Patent Rights

for the purpose of computing the minimum annual royalty and earned

royalty payments in any given country on the earliest of the dates

that a) the claim has been abandoned but not continued, b) the

patent expires, c) the patent is no longer maintained by the

Government, or d) all claims of the Licensed Patent Rights have

been held to be invalid or unenforceable by an unappealed or

unappealable decision of a court of competent jurisdiction or

administrative agency.

6.06 No multiple royalties shall be payable because any Licensed

Products or Licenced Processes are covered by more than one of the

Licensed Patent Rights.

6.07 On sales of Licensed Products by Licensee to sublicensees or

affiliated parties or on sales made in other than an arm's-length

transaction, the value of the Net Sales attributed under this

Article 6 to such a transaction shall be that which would have

been received in an arm's-length transaction, based on sales of

like quantity and quality products on or about the time of such

transaction.

6.08 As an additional royalty, Licensee agrees to pay PHS, within sixty

(60) days of PHS's submission of a statement and request for

payment, an amount equivalent to all reasonable expenses

previously incurred by PHS in the preparation, filing,

prosecution, and maintenance of Licensed Patent Rights. Licensee

further agrees to pay PHS annually, within sixty (60) days of

PHS's submission of a statement and request for payment, a royalty

amount equivalent to all such future patent expenses incurred

during the previous calendar year, as of the date the statement

and request for payment is sent by PHS to Licensee. Fifty percent

(50%) of the cumulative amount of such payments may be credited

against royalties due under Paragraph 6.03; however, the net

royalty payment in any calendar year may not be lower than the

minimum annual royalty specified in Appendix B. Licensee may elect

to surrender its rights in any country of the Licensed Territory

under any Licensed Patent Rights

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upon sixty (60) days' written notice to PHS and owe no payment

obligation under this paragraph for subsequent patent-related

expenses incurred in that country.

7. DOMESTIC AND FOREIGN PATENT FILING, PROSECUTION, AND MAINTENANCE

7.01 PHS agrees to take responsibility for, but to consult with the

Licensee in, the preparation, filing, prosecution, and maintenance

of any and all patent applications or patents included in the

Licensed Patent Rights and shall furnish copies of relevant

patent-related documents to Licensee.

7.02 Each party shall promptly inform the other as to all matters that

come to its attention that may affect the preparation, filing,

prosecution, or maintenance of the Licensed Patent Rights and

permit each other to provide comments and suggestions with respect

to the preparation, filing, and prosecution of Licensed Patent

Rights, which comments and suggestions shall be considered by the

other party.

8. RECORD KEEPING

8.01 Licensee agrees to keep accurate and correct records of Licensed

Products made, used, or sold and Licensed Processes practiced

under this Agreement appropriate to determine the amount of

royalties due PHS. Such records shall be retained for at least

five (5) years following a given reporting period. They shall be

available during normal business hours for inspection at the

expense of PHS by an accountant or other designated auditor

selected by PHS for the sole purpose of verifying reports and

payments hereunder. The accountant or auditor shall only disclose

to PHS information relating to the accuracy of reports and

payments made under this Agreement. If an inspection shows an

underreporting or underpayment in excess of five percent (5%) for

any twelve (12) month period, then Licensee shall reimburse PHS

for the cost of the inspection at the time Licensee pays the

unreported royalties, including any late charges as required by

Paragraph 7.06 of this Agreement. All payments required under this

Paragraph shall be due within thirty (30) days of the date PHS

provides Licensee notice of the payment due.

9. REPORTS ON PROGRESS, BENCHMARKS, SALES, AND PAYMENTS

9.01 Prior to signing this Agreement, Licensee has provided to PHS a

written commercialization plan ("Commercial Development Plan")

under which Licenses intends to bring the subject matter of the

Licensed Patent Rights into commercial use. The Commercial

Development Plan is hereby incorporated by reference into this

Agreement. Based on this plan, performance benchmarks are

determined as specified in Appendix E ("Benchmarks").

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9.02 Licensee shall provide written annual reports on its product

development progress or efforts to commercialize under the

Commercial Development Plan for each of the Licensed Fields of Use

within sixty (60) days after December 31 of each calendar year.

These progress reports shall include, but not be limited to:

progress on research and development, status of applications for

regulatory approvals, manufacturing, sublicensing, marketing, and

sales during the preceding calendar year, as well as plans for the

present calendar year. If reported progress differs from that

projected in the Commercial Development Plan and Benchmarks,

Licensee shall explain the reasons for such differences. Licensee

may propose amendments in any such annual report to the Commercial

Development Plan, acceptance of which by PHS may not unreasonably

be denied. Licensee agrees to provide any additional data

reasonably required by PHS to evaluate Licensee's performance.

Licensee may amend the Benchmarks at any time upon written consent

by PHS. PHS shall not unreasonably withhold approval of any

request of Licensee to extend the time periods of this schedule if

such request is supported by a reasonable showing by Licensee of

diligence in its performance under the Commercial Development Plan

and toward bringing the Licensed Products to the point of

practical application as defined in 37 CFR 404.3(d). Licensee

shall amend the Commercial Development Plan and Benchmarks at the

request of PHS to address any Licensed Fields of Use not

specifically addressed in the plan originally submitted.

9.03 Licensee shall report to PHS the date of the First Commercial Sale

in each country in the Licensed Territory within thirty (30) days

of such occurrence.

9.04 Licensee shall submit to PHS within sixty (60) days after each

calendar half-year ending June 30 and December 31 a royalty report

setting forth for the preceding half-year period the amount of the

Licensed Products sold or Licensed Processes practiced by or on

behalf of Licensee in each country within the Licensed Territory,

the Net Sales, and the amount of royalty accordingly due. With

each such royalty report, Licensee shall submit payment of the

earned royalties due. If no earned royalties are due to PHS for

any reporting period, the written report shall so state. The

royalty report shall be certified as correct by an authorized

officer of Licensee and shall include a detailed listing of all

deductions made under Paragraph 2.05 to determine Net Sales made

under Article 6 to determine royalties due.

9.05 Licensee agrees to forward semi-annually to PHS a copy of such

reports received by Licensee from its sublicensees during the

preceding half-year period as shall be pertinent to a royalty

accounting to PHS by Licensee for activities under the sublicense.

9.06 Royalties due under Article 6 shall be paid in D.S. dollars. For

conversion of foreign currency to U.S. dollars, the conversion

rate shall be the rate quoted in The Wall Street Journal on the

day that the payment is due. All checks and bank drafts shall be

drawn on

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United States banks and shall be payable to NIH/Patent Licensing

at the address shown on the Signature Page below. Any loss of

exchange, value, taxes, or other expenses incurred in the transfer

or conversion to U.S. dollars shall be paid entirely by Licensee.

All royalty payments due under this Agreement shall be mailed to

the following address: NIH, P.O. Box 360120, Pittsburgh,

Pennsylvania 15251-6120. The royalty report required by paragraph

9.04 of this Agreement shall accompany each such payment and a

copy of such report shall also be mailed to PHS at its address for

notices indicated on the Signature Page of this Agreement.

9.07 Late charges will be applied to any overdue payments as required

by the U.S. Department of Treasury in the Treasury Fiscal

Requirements Manual, Section 8025.40. The payment of such late

charges shall not prevent PHS from exercising any other rights it

may have as a consequence of the lateness of any payment.

9.08 All plans and reports required by this Article 9 and marked

"confidential" by Licensee shall be treated by PHS as commercial

and financial information obtained from a person and as privileged

and confidential and, to the extent permitted by law, shall not be

subject to disclosure under the Freedom of Information Act, 5

U.S.C. Section 552.

10. PERFORMANCE

10.01 Licensee shall use its reasonable best eff