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                                                                   Exhibit 10.92
                                            ***TEXT OMITTED AND FILED SEPARATELY
                                                CONFIDENTIAL TREATMENT REQUESTED
                                          UNDER 17 C.F.R. SECTIONS 200.80(b)(4),
                                                            200.83 AND 240.24b-2

                         NON-EXCLUSIVE LICENSE AGREEMENT

       THIS NON-EXCLUSIVE LICENSE AGREEMENT (the "Agreement") is entered into as
of August 17, 2001 (the "Effective Date"), by and between EPIMMUNE INC., a
corporation organized under the laws of the State of Delaware, having offices at
5820 Nancy Ridge Drive, San Diego, California 92121 ("Epimmune"), and BIOSITE
INCORPORATED, a company organized under the laws of the State of Delaware,
having offices at 11030 Roselle Street, Suite D, San Diego, California 92121
("Biosite"). Epimmune and Biosite may each be referred to herein individually as
a "Party" and collectively as the "Parties."

       WHEREAS, Epimmune has developed and owns the PADRE(R) (defined below)
technology; and

       WHEREAS, Biosite wishes to obtain, and Epimmune is willing to grant, a
non-exclusive license under the Licensed Technology (as defined below) on the
terms and subject to the conditions set forth herein.

       NOW, THEREFORE, in consideration of the mutual covenants and promises
hereinafter set forth, the Parties hereby agree as follows:

                                    ARTICLE 1

                                   DEFINITIONS

       1.1 "AFFILIATE" shall mean any corporation or other entity which
controls, is controlled by, or is under common control with, another corporation
or entity. A corporation or other entity shall be regarded as in control of
another corporation or entity if it owns or directly or indirectly controls more
than fifty percent (50%) of the voting securities or other ownership interest of
the other corporation or entity.

       1.2 "CONFIDENTIAL INFORMATION" shall mean any confidential or proprietary
information of a Party or its Affiliate, including information related to the
Licensed Technology, and any other information relating to any compound,
research project, work in process, future development, scientific, engineering,
manufacturing, marketing, business plan, financial or personnel matter relating
to such Party or its Affiliate, its present or future products, sales,
suppliers, customers, employees, investors or business, whether in oral,
written, graphic or electronic form, including, without limitation, trade
secrets, processes, formulae, data and know-how, improvements, inventions,
techniques, biological materials, marketing plans, strategies, forecasts and
customer and contact lists; in each case which is marked, identified as or
otherwise acknowledged to be confidential at the time of disclosure to the other
party.

       1.3 "CONTROL" shall mean possession of the ability to grant a license or
sublicense as provided for herein without violating the terms of any agreement
or other arrangement with any Third Party.

       1.4 "FIELD" shall mean [...***...].

       1.5 "KNOW-HOW" shall mean all inventions, discoveries, materials,
technology, trade secrets, data, processes, techniques, procedures,
compositions, devices, methods, formulas, protocols and information, or other
know-how, whether or not patentable, which (i) are Controlled by Epimmune as of
the Effective Date or during the Term, (ii) are not generally known, and (iii)
relate to PADRE(R), its manufacture or use, or PADRE(R) Improvements (defined in
Section 5.1(b)).

       1.6 "LICENSED TECHNOLOGY" shall mean, to the extent necessary or useful
for research, development, manufacture, use, sale or import of Products, all
Patent Rights and Know-How.

       1.7 "PADRE(R)" shall mean a peptide capable of binding antigen binding
sites on major histocompatibility complex (MHC) molecules encoded by
substantially all alleles of a DR locus, including, without


                                               *CONFIDENTIAL TREATMENT REQUESTED
<PAGE>

limitation, a composition comprising a peptide recited in the claims of United
States Patent Application Serial No. 08/121,101 filed September 14, 1993 and any
patent applications, U.S., international and foreign, that derive priority from
such patent application, such as continuing applications (including, without
limitation, any continuations, continuations-in-part or divisionals thereof) and
any patents issuing therefrom. Such peptides are also referred to as pan DR
binding peptides and include, without limitation, AKXVAAWTLKAAA (using the
single letter designation for amino acids), wherein X is cyclohexylalanine or
phenylalanine, and other peptides claimed and/or disclosed in the patent
applications described in this Section 1.7.

       1.8 "PADRE(R) CONSTRUCT" shall mean any biological construct comprised of
PADRE(R) fused or linked to another molecule or complex of molecules or DNA
encoding PADRE(R) fused to DNA encoding a polypeptide.

       1.9 "PATENT RIGHTS" shall mean all patents and patent applications,
including provisional applications, and all patents issuing thereon (including
utility, model and design patents and certificates of invention), together with
all reissue patents, patents of addition, divisions, renewals, continuations,
continuations-in-part, continued prosecution applications, requests for
continued examination, substitutions, additions, extensions or restorations (by
existing or future extension or restoration mechanisms, including, without
limitation, supplemental protection certificates), registrations, confirmations,
reexaminations and foreign counterparts of any of the foregoing, which (i) are
Controlled by Epimmune as of the Effective Date or during the Term, and (ii)
relate to PADRE(R) or PADRE(R) Improvements (defined in Section 5.1(b))
including, without limitation, the patents and patent applications listed on
Appendix I.

       1.10 "PRODUCT" shall mean any product, other than a vaccine, comprising
or derived directly or indirectly from an antibody or a fragment thereof that is
induced by immunization of animals with an antigen formulated with or comprised
of a PADRE(R) Construct.

       1.11 "SUBLICENSEE" shall mean any Affiliate of Biosite or any Third Party
to which Biosite has granted a sublicense pursuant to Section 2.2.

       1.12 "THIRD PARTY" shall mean any entity other than Epimmune or Biosite
or an Affiliate of Epimmune or Biosite.

                                    ARTICLE 2

                                GRANT OF LICENSE

       2.1 LICENSE. Subject to the terms and conditions of this Agreement,
Epimmune hereby grants to Biosite a non-exclusive, non-transferable (except in
accordance with Section 8.1), irrevocable (except in accordance with Section
7.2), [...***...], worldwide license, with the right to grant sublicenses in
accordance with Section 2.2, under the Licensed Technology: (i) to make, have
made and use PADRE(R) as part of a PADRE(R) Construct solely for the purpose of
generating antibodies in connection with the research and development of
Products for use in the Field, and (ii) to make, have made, use, offer for sale,
sell, have sold and import Products for use in the Field. Nothing herein shall
be construed as granting Biosite the right to use, sell, have sold, make, have
made, import or otherwise transfer or commercialize: (i) PADRE(R) as a component
of any pharmaceutical product, or (ii) any therapeutic vaccines or prophylactic
vaccines using PADRE(R).

       2.2 SUBLICENSING RIGHTS.

              (a) Biosite shall have the right to grant sublicenses under the
rights granted in Section 2.1(i) solely to its Affiliates. Biosite may not
sublicense such rights to any Third Party, provided, however, that Biosite may
permit collaborators of Biosite to prepare immunogens and/or conduct
immunizations using PADRE(R) Constructs, and to transfer such immunogens or
immunized animals or tissues or RNA extracted therefrom to Biosite for use to
generate antibodies in connection with the research and development off Products
for use in the Field. Biosite shall have the right to grant sublicenses under
the rights granted to it under Section 2.1(ii) to its Affiliates or to any Third
Party to which Biosite licenses rights to or transfers one or more Products,
subject to the


                                               *CONFIDENTIAL TREATMENT REQUESTED


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<PAGE>

terms and conditions of this Agreement. Biosite shall provide written notice to
Epimmune of any such sublicense within thirty (30) days after execution thereof.

              (b) Any sublicense granted by Biosite under this Agreement shall
be subject and subordinate to, and consistent with, the terms and conditions of
this Agreement. Biosite shall notify any Sublicensee of all rights and
obligations of Biosite under this Agreement applicable to such Sublicensee,
including, without limitation, Article 4.

              (c) If this Agreement terminates for any reason, any Sublicensee
shall automatically become a direct licensee of Epimmune with respect to the
rights originally sublicensed to it by Biosite, provided such Sublicensee did
not cause the termination of this Agreement and such Sublicensee agrees to
comply with all of the terms of this Agreement and assume the responsibilities
of Biosite hereunder, including, without limitation, the making of payments and
reports directly to Epimmune and the remedying of any breach by Biosite of this
Agreement, to the extent reasonably practicable.

       2.3 DISCLOSURE OF LICENSED TECHNOLOGY. Within [...***...], Epimmune shall
disclose and transfer to Biosite all Know-How in existence as of [...***...],
and the practice thereof in accordance with the license granted under Section
2.1.

       2.4 [...***...]

                                    ARTICLE 3

                               PAYMENT OBLIGATIONS

       3.1 LICENSE FEE. In consideration for the license granted hereunder,
Biosite agrees to pay to Epimmune [...***...].

       3.2 LATE PAYMENT. In the event that any payment of the license fee under
Section 3.1, or part thereof, is not made when due, the payment, or part
thereof, shall accrue interest from the date due at the rate of [...***...];
provided, however, that in no event shall such rate exceed the maximum legal
annual interest rate. The payment of such interest shall not limit Epimmune from
exercising any other rights it may have as a consequence of the lateness of such
payment.

                                    ARTICLE 4

                                 CONFIDENTIALITY

       4.1 CONFIDENTIALITY. During the Term and for a period of [...***...]
thereafter, Epimmune will maintain in confidence all Confidential Information
disclosed by Biosite or its Affiliates hereunder, and Biosite will maintain in
confidence all Confidential Information disclosed by Epimmune or its Affiliates
hereunder. Neither Party will use, disclose or grant use of such Confidential
Information except as expressly authorized by this Agreement. To the extent that
disclosure is authorized by this Agreement, the disclosing Party will obtain
prior agreement from its employees, agents, consultants and Sublicensees to whom
disclosure is to be made to hold in confidence and not make use of such
information for any purpose other than those permitted by this Agreement. Each
Party will use at least the same standard of care as it uses to protect its own
Confidential Information to obligate such employees, agents, consultants and
Sublicensees not to disclose or make any unauthorized use of such Confidential
Information. Each Party will promptly notify the other upon discovery of any
unauthorized use or disclosure of the Confidential Information.

       4.2 EXCEPTIONS. The obligations of confidentiality contained in Section
4.1 will not apply to the extent that it can be established by the receiving
Party by competent written proof that such Confidential Information:

              (a) is now, or hereafter becomes, through no act or failure to act
on the part of the receiving


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Party, generally known or available to the public;

              (b) is known by the receiving Party at the time of receiving such
information or is developed by receiving Party thereafter in the course of work
entirely independent of and without reference to any Confidential Information
disclosed by the disclosing Party, in each case, as evidenced by its records; or

              (c) is hereafter furnished to the receiving Party by a Third
Party, as a matter of right and without restriction on disclosure, which Third
Party is not under an obligation of confidentiality to the disclosing Party.

       4.3 AUTHORIZED DISCLOSURE. Each Party may disclose the Confidential
Information of the other Party to the extent such disclosure (a) is the subject
of a written permission to disclose provided by such other Party, or (b) is
reasonably necessary in filing or prosecuting patent applications, prosecuting
or defending litigation or complying with applicable governmental regulations,
including, but not limited to the conduct by Biosite of any clinical trials or
registration of any Product, provided that if such Party is required to make any
such disclosure of such Confidential Information it will give reasonable advance
notice to the other Party of such disclosure requirement with an opportunity to
review and revise the proposed disclosure and, except to the extent
inappropriate in the case of patent applications, will use reasonable efforts to
secure confidential treatment of such information required to be disclosed.

       4.4 PRESS RELEASE. Except as otherwise provided in Section 4.3 above,
neither party shall disclose any terms or conditions of this Agreement to any
Third Party without the prior consent of the other party. Notwithstanding the
foregoing, the Parties agree that a press release announcing the matters covered
by this Agreement in substantially the form attached hereto as Appendix II will
be issued, and either Party may publicize the existence and general subject
matter of this Agreement consistent with such press release without the other
Party's approval.

                                    ARTICLE 5

                          INTELLECTUAL PROPERTY RIGHTS

       5.1 OWNERSHIP OF INVENTIONS.

              (a) Inventorship of inventions shall be determined in accordance
with the rules of inventorship under United States patent law.

              (b) Epimmune shall have sole ownership of all inventions,
discoveries, developments and improvements made, conceived or reduced to
practice in the course of activities conducted under this Agreement solely
pertaining to PADRE(R) or its manufacture or use, regardless of whether made
solely by employees and agents of Epimmune, solely by employees or agents of
Biosite or jointly by employees or agents of Epimmune and employees or agents of
Biosite ("PADRE(R) Improvements"), and all patent applications, patents and
other intellectual property rights directed to such PADRE(R) Improvements.
Biosite hereby irrevocably assigns to Epimmune all right, title and interest in
and to any such PADRE(R) Improvements and all patent applications, patents and
all other intellectual property rights directed to such PADRE(R) Improvements.
In the event that Biosite is legally unable to assign such rights to Epimmune,
then Biosite agrees either to waive the enforcement of such rights against
Epimmune and any sublicensees and assignees, or to grant Epimmune an exclusive,
irrevocable, perpetual, worldwide, fully-paid license, with right to sublicense
through multiple tiers of sublicense, to such rights.

              (c) Except as provided in Section 5.1(b), ownership of all
inventions, discoveries, developments and improvements conceived or reduced to
practice in the course of activities conducted under this Agreement, and all
patent applications, patents and other intellectual property rights directed to
such inventions, discoveries, developments and improvements, shall be determined
in accordance with inventorship (i.e., a Party shall solely own all such
inventions, discoveries, developments and improvements made solely by its
employees or agents, and the Parties shall jointly own all such inventions,
discoveries, developments and improvements made jointly by their respective
employees or agents). Each party shall have the right, subject to the provisions
of this


                                       4
<PAGE>

Agreement, to freely exploit, transfer, license or encumber its rights in any
jointly owned invention, discovery, development or improvement (or the patent
and other intellectual property rights therein) without the consent of, or
compensation or accounting to, the other party.

       5.2 FILING, PROSECUTION AND MAINTENANCE OF PATENTS AND PATENT
APPLICATIONS. Epimmune shall have the sole right to control the filing,
prosecution and maintenance of, all patent applications and patents included in
the Patent Rights, at Epimmune's expense. Epimmune shall keep Biosite advised of
the status of the actual and prospective patent filings included in the Patent
Rights, including, without limitation, the filing of any patent application or
grant of any patent, and Epimmune shall allow Biosite to provide input related
to any patent application included in the Patent Rights that is relevant to any
Product. As between the Parties, the Party that owns any patent applications and
patents arising in the course of activities conducted under this Agreement shall
have the sole right, at its own expense, to control, and the other Party shall
reasonably cooperate with such Party to facilitate, the filing, prosecution and
maintenance of such patent applications and patents. With respect to joint
patent applications or patents arising in the course of activities conducted
under this Agreement, if any, the Parties will share equally the control of and
expenses associated with the filing, prosecution and maintenance of such joint
patent applications or patents, unless a party disclaims ownership of any such
joint patent application or patent, in which case such party shall assign to the
other party all its right, title and interest in and to any such joint patent
application or patent, and such other party shall have the sole right to
control, file, prosecute and maintain any such joint patent application or
patent, in its sole discretion and at its sole expense.

       5.3 INFRINGEMENT ACTIONS.

              (a) Epimmune shall have the sole right, at its discretion, to
prosecute any and all infringements of any Patent Rights, whether inside or
outside the Field.

              (b) Biosite shall have the first right, in its sole discretion to
control at its own expense the defense of all charges of infringement by any
Third Party arising as a result of the development, manufacture, use or sale of
any Product by Biosite or any of its Sublicensees. Epimmune shall have the right
to be represented by counsel of its own selection, at its own expense, and shall
cooperate fully in the defense of such suit and furnish to Biosite all evidence
and assistance in its control. If Biosite declines to bring such action or
proceeding, then Epimmune shall have the right, at its discretion, to control at
its own expense the defense of such charges of infringement, and Biosite shall
have the right, at its own expense, to be represented in any such action by
counsel of its own choice.

              (c) The party controlling the suit under Section 5.3(c) may not
settle the suit or otherwise consent to an adverse judgment in such suit, if
such settlement or judgment would diminish the rights or interests of the
non-controlling party, without the prior written consent of the non-controlling
party, which consent shall not be unreasonably withheld or delayed.

                                    ARTICLE 6

                     REPRESENTATIONS; WARRANTIES; COVENANTS

       6.1 CORPORATE POWER. Each Party hereby represents and warrants that it is
duly organized, validly existing and in good standing under the laws of the
state or jurisdiction of its incorporation or formation and has full corporate
power and authority to enter into this Agreement and to carry out the provisions
hereof.

       6.2 DUE AUTHORIZATION. Each Party hereby represents and warrants that it
is duly authorized to execute and deliver this Agreement and to perform its
obligations hereunder.

       6.3 BINDING AGREEMENT. Each Party hereby represents and warrants that
this Agreement is a legal and valid obligation binding upon it and is
enforceable in accordance with its terms, and that the execution, delivery and
performance of this Agreement by such Party does not conflict with any
agreement, instrument or understanding, oral or written, to which it is a party
or by which it may be bound, nor violate any law or regulation of any court,
governmental body or administrative or other agency having authority over it.


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<PAGE>

       6.4 EXISTING RIGHTS. Epimmune represents and warrants that, as of the
Effective Date, the Patent Rights are existing and, to the best of its
knowledge, are not invalid or unenforceable, in whole or in part.

       6.5 RIGHT AND TITLE. Epimmune represents and warrants that, as of the
Effective Date, to the best of its knowledge, it owns the sole right, title and
interest in and to the Licensed Technology.

       6.6 DISCLAIMER OF WARRANTIES. EXCEPT AS EXPRESSLY SET FORTH IN THIS
AGREEMENT, NEITHER PARTY MAKES ANY REPRESENTATION OR WARRANTY TO ANY OTHER PARTY
OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING, WITHOUT LIMITATION, ANY WARRANTY OF
TITLE, NON-INFRINGEMENT, MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.

       6.7 GOVERNMENTAL APPROVALS; COMPLIANCE WITH APPLICABLE LAWS. Biosite
shall be responsible for obtaining all necessary governmental approvals for the
conduct of any research and development of Products, including the conduct of
any clinical trials, at Biosite's expense. Biosite shall conduct such activities
in compliance with all applicable laws and regulations.

       6.8 INDEMNIFICATION.

              (a) Biosite hereby agrees to save, defend, indemnify and hold
harmless Epimmune and its officers, directors, employees, consultants and agents
from and against any and all losses, damages, liabilities, expenses and costs,
including reasonable legal expense and attorneys' fees ("Losses"), to which any
of them may become subject as a result of any claim, demand, action or
proceeding by any Third Party to the extent such Losses arise out of (i) the
research, development, manufacture, use or sale by Biosite or its Sublicensees
of Products, (ii) the conduct of any research and development by Biosite or its
Sublicensees, including, without limitation, clinical trials, conducted with
respect to the Products, (iii) a breach by Biosite of any of its representations
and warranties contained in this Article 6, (iv) any material breach by Biosite
of this Agreement, (v) any Product, or (vi) the gross negligence or willful
misconduct of Biosite or its Affiliates or Sublicensees in performance of this
Agreement, except to the extent such Losses result from the negligence or
willful misconduct of Epimmune. In the event a party entitled to indemnification
under this Section 6.8(a) seeks indemnification hereunder, it shall inform
Biosite of a claim as soon as reasonably practicable after it receives notice of
the claim, shall permit Biosite to assume direction and control of the defense
of the claim (including the right to settle the claim solely for monetary
consideration), and shall cooperate as requested (at the expense of Biosite) in
the defense of the claim.

              (b) Epimmune hereby agrees to save, defend, indemnify and hold
harmless Biosite and its respective officers, directors, employees, consultants
and agents from and against any and all Losses to which any of them may become
subject as a result of any claim, demand, action or proceeding by any Third
Party to the extent such Losses arise out of (i) a breach by Epimmune of any of
its representations and warranties contained in this Article 6, (ii) any
material breach by Epimmune of this Agreement, or (iii) the gross negligence or
willful misconduct of Epimmune or its Affiliates in performance of this
Agreement, except to the extent such Losses result from the negligence or
willful misconduct of Biosite. In the event a Party entitled to indemnification
under this Section 6.8(b) seeks indemnification hereunder, it shall inform
Epimmune of a claim as soon as reasonably practicable after it receives notice
of the claim, shall permit Epimmune to assume direction and control of the
defense of the claim (including the right to settle the claim solely for
monetary consideration), and shall cooperate as requested (at the expense of
Epimmune) in the defense of the claim.

                                    ARTICLE 7

                                TERM; TERMINATION

              7.1 TERM. This Agreement shall commence as of the Effective Date
and shall continue indefinitely, unless terminated as provided herein (the
"Term").

              7.2 TERMINATION. Biosite may terminate this Agreement at any time
by written notice to Epimmune. Epimmune may terminate this Agreement prior to
the expiration of the Term only if Biosite fails to make payment


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when due under Section 3.1, and such breach is not cured within [...***...]
after Epimmune provides Biosite with written notice thereof.

       7.3 BANKRUPTCY. In the event bankruptcy proceedings are instituted
against Epimmune or on Epimmune's behalf, then the Parties hereby acknowledge
and agree that Biosite may elect to retain its rights under this Agreement as
provided in 11 U.S.C. Section 365(n).

       7.4 EFFECT OF TERMINATION. Upon termination of this Agreement, all rights
under the Licensed Technology shall revert to Epimmune; provided, however, that
Biosite and its Sublicensees shall have the right to sell their inventory of
Products then on hand. Within thirty (30) days following the expiration or
termination of this Agreement, each Party shall return to the other Party, or
destroy, upon the written request of the other Party, any and all Confidential
Information of the other Party in its possession. Expiration or termination of
this Agreement shall not relieve the Parties of any obligation accruing prior to
such expiration or termination. The provisions of Sections 2.4, 6.6, 6.8 and 7.3
and Articles 1, 4, 5, and 8 shall survive termination or expiration of this
Agreement.

                                    ARTICLE 8

                                  MISCELLANEOUS

       8.1 ASSIGNMENT. Except as expressly provided hereunder, neither this
Agreement nor any rights or obligations hereunder may be assigned or otherwise
transferred by either Party without the prior written consent of the other Party
(which consent shall not be unreasonably withheld); provided, however, that
either Party may assign this Agreement and its rights and obligations hereunder
without the other Party's consent (a) with respect to Epimmune, in connection
with the transfer or sale to a Third Party of all or substantially all of the
business of Epimmune to which this Agreement relates, whether by merger, sale of
stock, sale of assets or otherwise, (b) with respect to Biosite, in connection
with the transfer or sale to a Third Party of all or substantially all of the
business of Biosite related to commercial in vitro diagnostic products to which
this Agreement relates, whether by merger, sale of stock, sale of assets or
otherwise, or (c) to any Affiliate. The rights and obligations of the parties
under this Agreement shall be binding upon and inure to the benefit of the
successors and permitted assigns of the parties. Any assignment not in
accordance with this Agreement shall be void.

       8.2 FORCE MAJEURE. No Party shall be held liable or responsible to any
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 (other
than non-payment) when such failure or delay is caused by or results from causes
beyond the reasonable control of the affected Party, including, without
limitation, fire, floods, earthquakes, natural disasters, embargoes, war, acts
of war (whether war be declared or not), insurrections, riots, civil commotions,
strikes, power outages, lockouts or other labor disturbances, acts of God or
acts, omissions or delays in acting by any governmental authority or any other
Party to this Agreement.

       8.3 GOVERNING LAW. This Agreement shall be governed by, and construed and
enforced solely and exclusively in accordance with, the laws of the State of
California, U.S.A., without regard to its choice of law provisions.

       8.4 LIMITATION OF LIABILITY. EXCEPT (A) TO THE EXTENT ANY AMOUNTS PAYABLE
UNDER ARTICLE 3 CONSTITUTE PROFIT, (B) FOR LIABILITY FOR BREACH OF ARTICLE 4 OR
(C) FOR ANY CLAIM (OUTSIDE OF THE SCOPE OF THIS AGREEMENT) OF INFRINGEMENT OF
THE LICENSED TECHNOLOGY, NEITHER PARTY SHALL BE LIABLE TO THE OTHER FOR ANY
SPECIAL, PUNITIVE, CONSEQUENTIAL, INCIDENTAL OR INDIRECT DAMAGES ARISING OUT OF
THIS AGREEMENT, HOWEVER CAUSED, UNDER ANY THEORY OF LIABILITY. NOTWITHSTANDING
THE FOREGOING, THE LIMITATIONS ON DAMAGES SET FORTH IN THIS SECTION 8.4 SHALL IN
NO WAY LIMIT A PARTY'S OBLIGATIONS TO MAKE INDEMNIFICATION PAYMENTS UNDER
SECTION 6.8.

       8.5 WAIVER. Except as specifically provided for herein, the waiver from
time to time by a Party of any right or failure to exercise any remedy shall not
operate or be construed as a continuing waiver of the same right or remedy or of
any other of such Party's rights or remedies provided under this Agreement.


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       8.6 SEVERABILITY. In case any provision of this Agreement shall be
invalid, illegal or unenforceable, the validity, legality and enforceability of
the remaining provisions shall not in any way be affected or impaired thereby.

       8.7 INDEPENDENT CONTRACTORS. It is expressly agreed that Epimmune and
Biosite shall be independent contractors and that the relationship among them
shall not constitute a partnership, joint venture or agency of any kind. No
Party shall have the authority to make any statements, representations or
commitments of any kind, or to take any action, which shall be binding on any
other Party, without the prior written consent of such other Party.

       8.8 NOTICES. All notices and other communications provided for hereunder
shall be in writing and shall be deemed to have been duly given upon the date of
receipt to the following addresses or facsimile numbers:

       If to Epimmune: EPIMMUNE INC.

       5820 Nancy Ridge Drive
       San Diego, CA  92121
       United States
       Attention: President
       Facsimile: (858) 860-2600

       If to Biosite: BIOSITE INCORPORATED

       11030 Roselle Street, Suite D
       San Diego, California  92121
       Attention: President
       Facsimile: (858) 623-1392

       With a copy to: Gray Cary Ware & Freidenrich LLP

       4365 Executive Drive, Suite 1600
       San Diego, California  92121
       Attention:  Mark R. Wicker
       Facsimile: (858) 677-1477

       Any Party may by like notice specify or change an address to which
notices and communications shall thereafter be sent.

       8.9 ENTIRE AGREEMENT; AMENDMENT. This Agreement (including Appendix I and
Appendix II attached hereto) sets forth all of the agreements and understandings
between the Parties with respect to the subject matter hereof, and supersedes
and terminates all prior and contemporaneous agreements and understandings
between the Parties with respect to the subject matter hereof. There are no
agreements or understandings with respect to the subject matter hereof, either
oral or written, between the Parties other than as set forth herein. Except as
expressly set forth in this Agreement, no subsequent amendment, modification or
addition to this Agreement shall be binding upon the Parties hereto unless
reduced to writing and signed by the respective authorized officers of Epimmune
and Biosite.

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

       8.11 COUNTERPARTS. This Agreement may be executed in two or more
counterparts, by facsimile, or both, each of which shall be deemed an original,
but all of which together shall constitute one and the same instrument.


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       IN WITNESS WHEREOF, the Parties have executed this Agreement as of the
date first set forth above.

EPIMMUNE INC.                           BIOSITE INCORPORATED

By: /s/ Robert De Vaere                 By: /s/ Kim D. Blickenstaff
    -----------------------------           ------------------------------
Name: Robert De Vaere                   Name: Kim D. Blickenstaff
     ----------------------------             ----------------------------
Title:  VP, Finance & CFO               Title: President and CEO
      ---------------------------              ---------------------------


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                                   APPENDIX I

[...***...]


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APPENDIX II

                              FORM OF PRESS RELEASE

[...***...]


                                               *CONFIDENTIAL TREATMENT REQUESTED


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