STOCK PURCHASE AGREEMENT

         THIS STOCK  PURCHASE  AGREEMENT  dated as of  September  15,  1995 (the
"Agreement"),  is entered  into  between  THE  IMMUNE  RESPONSE  CORPORATION,  a
Delaware corporation (the "Company"),  having a place of business at 5935 Darwin
Court, Carlsbad, California 92008, U.S.A., and TRINITY MEDICAL GROUP, CO., LTD.,
a Thai  limited  company (the  "Investor"),  having a place of business at 425/5
Silom No. 7, Silom Road,  Bangkok 10500,  Thailand.  The parties hereby agree as
follows:

         1. Purchase and Sale of Shares.

            1.1 Sale and  Issuance  of Shares.  On the terms and  subject to the
conditions of the Agreement,  the Investor shall purchase, and the Company shall
sell and issue to the Investor, the following number of shares (the "Shares") of
the Company's Common Stock on the following dates (each, a "Closing Date"),  for
the purchase price of US$15.00 per share (the "Purchase Price") :

            1.1.1 333,334  shares on April 30, 1996 (the "First Closing Date") ;
and

            1.1.2 333,333  shares on the date (the "Second  Closing Date") which
is thirty (30) days after the date on which the  Investor  receives the required
marketing  approval  from the  governing  health  authority  of Thailand for the
Product; and

            1.1.3 333,333 shares on the date (the "Third Closing Date") which is
thirty  (30) days after the date on which the  Investor  receives  the  required
factory  establishment  license,  or other required  approval from the governing
health  authority of Thailand to manufacture  the Product in Thailand,  provided
that the parties have entered into a mutually acceptable  manufacturing  license
agreement  pursuant  to  the  provisions  of  Section  5.4 of  the  License  and
Collaboration Agreement.


            1.2 Condition Precedent to the First Closing.  The obligation of the
Investor to Purchase the Shares on the First  Closing Date shall be  conditioned
upon the Company  submitting  to the  Investor,  on or before the First  Closing
Date, evidence certified by a duly authorized  representative of the Company and
reasonably  satisfactory to the Investor that the Company has the legal right to
commence a Phase 3 clinical trial of the Product in the United States.


            1.3  Closings.  Each such purchase and sale of the Shares shall take
place on the applicable Closing Date, at such time and place (outside the United
States) as the  Company and the  Investor  mutually  agree upon,  verbally or in
writing  (which times and places each are  designated as a  "Closing").  At each
Closing,  the Company shall  deliver to the Investor a certificate  representing
the Shares which the Investor is purchasing on such date against  payment of the
Purchase  Price  therefor.  The  Investor  shall  make each such  payment to the
Company  by a bank wire in same day funds in the  amount of the  Purchase  Price
payable to the Company's order.

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            1.4 Collateral  for Purchase Price on First Closing.  The Investor's
obligation to pay the Purchase  Price on the First Closing Date shall be secured
by an  irrevocable  letter of credit  (the  "Letter of Credit")  satisfying  the
following  conditions:  (a) the issuing bank shall be Bangkok  Metropolitan Bank
Public  Company  Limited;  (b) the account party shall be the Investor;  (c) the
sole  beneficiary  shall be the Company;  (d) the principal  amount shall not be
less than  US$5,000,000;  (e) the  maturity  date  shall be not prior to May 15,
1996; (f) either (i) the beneficiary  shall have the right to present the Letter
of Credit  for draw at a branch of  Bangkok  Metropolitan  Bank  Public  Company
Limited  located in the  United  States,  or (ii) the Letter of Credit  shall be
confirmed  by a  United  States  bank  located  in the  United  States,  and the
beneficiary  shall have the right to present  the Letter of Credit for draw at a
branch of the confirming  bank located in the United  States;  (g) the Letter of
Credit shall be payable in United States dollars in immediately available funds;
(h) the Letter of Credit shall not be amended  without the prior express written
consent of the  beneficiary;  (i) the  Letter of Credit  shall be subject to the
Uniform  Customs and Practices for  Documentary  Credits;  and (j) the Letter of
Credit shall be in form and content reasonably acceptable to the Company and the
only condition of payment shall be the presentation of

      Any  statement   purportedly  signed  by  an  officer  of  the
      Beneficiary, stating that Trinity Medical Group, Co., Ltd. has
      failed to make  payment  of the  purchase  price  owing to the
      Beneficiary  on April 30, 1996,  pursuant to the provisions of
      the Stock Purchase  Agreement dated as of September ___, 1995,
      between the Beneficiary and Trinity Medical Group, Co., Ltd.



The  Investor  shall  deliver the Letter of Credit to the Company not later than
sixty (60) days after the date of the Agreement. The Company's obligations under
the Agreement are conditioned upon its receipt of the Letter of Credit.

            1.5 Definitions. The following terms, as used herein, shall have the
following meanings:

            "Affiliate" shall mean, with respect to any Person, any other Person
which  directly or indirectly  controls,  is  controlled  by, or is under common
control with,  such Person.  A Person shall be regarded as in control of another
Person if it owns,  or directly or indirectly  controls,  at least forty percent
(40%) of the voting stock or other ownership interest of the other Person, or if
it directly or  indirectly  possesses the power to direct or cause the direction
of the management and policies of the other Person by any means whatsoever.

            "Common Stock" shall mean the Common Stock,  par value US$0.0025 per
share of the Company.

            "License  and  Collaboration  Agreement"  shall mean the License and
Collaboration Agreement dated as of the date hereof, between the Company and the
Investor (as the same may be amended or restated from time to time).

            "Material  Adverse Effect" shall mean, with respect to any Person, a
material  adverse effect on the condition  (financial or  otherwise),  business,
assets,  results of  operations  of such Person and, in the case of the Company,
the Subsidiaries taken as a

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<PAGE>

whole.

            "1934  Act"  shall  mean the  Securities  Exchange  Act of 1934,  as
amended, and the rules and regulations promulgated thereunder.

            "1933 Act" shall mean the  Securities  Act of 1933, as amended,  and
the rules and regulations promulgated thereunder.

            "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.

            "Product" shall mean a certain  immunotherapeutic product which uses
inactivated  human   immunodeficiency  virus  depleted  of  its  gp120  envelope
administered in Incomplete Freund's Adjuvant.

            "Subsidiaries" shall mean TargeTech, Inc., and I. R. C. Inc.

         2.  Representations  and Warranties of the Company.  The Company hereby
represents and warrants to the Investor that:

            2.1 Organization, Good Standing and Qualification.  The Company is a
corporation duly organized, validly existing and in good standing under the laws
of the State of Delaware and has all requisite  corporate power and authority to
carry on its  business  as now  conducted.  The  Company  is duly  qualified  to
transact  business  and is in good  standing in each  jurisdiction  in which the
failure so to qualify would have a Material Adverse Effect.

            2.2 Authorization.  All corporate action on the part of the Company,
its officers,  directors and stockholders  necessary for (a) the  authorization,
execution and delivery of the Agreement,  (b) the performance of all obligations
of the Company hereunder,  and (c) the  authorization,  issuance (or reservation
for  issuance)  and delivery of the Shares being sold  hereunder,  to the extent
that the foregoing requires performance on or prior to a Closing, has been taken
or will be taken on or prior to such Closing, and the Agreement  constitutes the
valid and legally  binding  obligation of the Company,  enforceable  against the
Company in accordance with its terms.

            2.3 Valid Issuance of Shares. The Shares which is being purchased by
the Investor  hereunder,  when issued, sold and delivered in accordance with the
terms hereof, for the consideration  expressed herein,  will be duly and validly
issued, fully paid and nonassessable and, based in part upon the representations
of the  Investor  in the  Agreement,  will be  issued  in  compliance  with  all
applicable  federal and state securities laws.

            2.4 Governmental Consents.  The execution,  delivery and performance
by the Company of the Agreement require no action by or in respect of, or filing
with,  any  governmental  body,  agency,  or official  other than (a)  post-sale
filings  pursuant to applicable  state and federal  securities  laws,  which the
Company  undertakes to file within the applicable  time periods and (b) any such
action  or  filing  as to  which  the  failure  to make  or  obtain  would  not,
individually or in the aggregate, have a Material Adverse Effect.

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<PAGE>

            2.5 SEC Filings; Financial Statements.

            2.5.1 The  Company  has  delivered  to the  Investor  (a) the annual
report on Form 10-K for its fiscal year ended 1994, (b) its quarterly  report on
Form 10-Q for its fiscal  quarters  ended March 31, 1995 and June 30, 1995,  (c)
its  proxy or  information  statement  relating  to the  annual  meeting  of the
stockholders  of the  Company  held on June 14,  1995,  and (d) all of its other
reports,  statements,  schedules  and  registration  statements  filed  with the
Securities and Exchange Commission (the "SEC") since December 31, 1994.

            2.5.2 As of its filing  date,  each such report or  statement  filed
pursuant to the 1934 Act did not contain any untrue statement of a material fact
or omit to state any material  fact  necessary  in order to make the  statements
made therein,  in the light of the circumstances under which they were made, not
misleading.

            2.5.3 The audited  consolidated  financial  statement  and unaudited
consolidated  interim financial  statement of the Company included in its annual
report on Form  10-K and the  quarterly  reports  on Form  10-Q  referred  to in
Section 2.5.1 fairly present,  in conformity with generally accepted  accounting
principles applied on a consistent basis, the consolidated financial position of
the Company and its consolidated  subsidiaries as of the dates thereof and their
consolidated  results of  operations  and changes in financial  position for the
periods then ended.

            2.6 The  Company  has not  offered  the  Shares to any person in the
United States,  any identifiable group of U. S. citizens abroad, or to any U. S.
Person (as defined in Regulation S promulgated under the 1933 Act by the SEC for
offers and sales of securities occurring outside the United States (" Regulation
S")).

            2.7 At the time the buy order was originated, the Company reasonably
believed the Investor was outside the United States and was not a U. S. Person.

            2.8 The Company reasonably  believes that the sale of Shares has not
been  prearranged  with a buyer in the United  States.

            2.9 The  Company  has not engaged nor is it aware that any party has
engaged,  and the Company will not engage, in any "directed selling efforts" (as
defined in Regulation  S) in the United  States with respect to the Shares.  The
Company  has not taken nor is it aware that  anyone has taken,  and the  Company
will not take directly or  indirectly,  or cause anyone to take, any action that
constituted or  constitutes,  was designed to constitute or reasonably  might be
expected to cause or result in stabilization or manipulation of the market price
for the  Common  Stock.

            2.10 The Company (a) is a "domestic issuer" and a "reporting issuer"
(as such terms are defined in Rule 902 of  Regulation  S), and (b) has filed all
material  required  to be filed by it pursuant  to the  requirements  of Section
13(a) or of 15(d) the 1934 Act for at least the twelve (12)  months  immediately
preceding  the date  hereof.  The Common  Stock  trades on the  Nasdaq  National
Market.

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<PAGE>

            3. Representations and Warranties of the Investor.  The Agreement is
made with the  Investor  in  reliance  upon the  Investor's  representation  and
warranties to the Company,  which by such Investor's  execution of the Agreement
the Investor hereby confirms, that:

            3.1 Reliance on  Representations.  The Investor has been advised and
acknowledges  (a) that the Shares have not been and will not be registered under
the 1933  Act,  the  securities  laws of any state of the  United  States or the
securities  laws of any other  country;  and (b) that in issuing and selling the
Shares to the Investor  pursuant  hereto,  the Company is relying upon the "safe
harbor" provided by Regulation S.

            3.2  Organization  and Existence.  The Investor is a limited company
duly organized, validly existing and in good standing under the laws of Thailand
and  has  all  corporate   powers  and  all  material   governmental   licenses,
authorizations,  permits,  consents  and  approvals  required  to  carry  on its
business as now conducted, except for those licenses,  authorizations,  permits,
consents and  approvals the absence of which would not,  individually  or in the
aggregate, have a Material Adverse Effect.

            3.3   Corporate   Authorization.   This   execution,   delivery  and
performance by the Investor of the Agreement are within the corporate  powers of
the Investor and have been duly authorized by all necessary  corporate action on
the part of the  Investor.  The  Agreement  constitutes  its valid  and  legally
binding obligation, enforceable in accordance with its terms.

            3.4  Governmental  Authorization.  Except for the approval  from the
Bank of  Thailand  (" BOT")  for the  remittance  to the  Company  of the  funds
representing  the Purchase Price for the Shares  purchased at each Closing,  the
execution,  delivery and performance by the Investor of the Agreement require no
action by or in respect of, or filing with,  any  governmental  body,  agency or
official other than any such action or filing as to which the failure to make or
obtain would not,  individually  or in the  aggregate,  have a Material  Adverse
Effect.

            3.5  Non-Contravention.  The execution,  delivery and performance by
the Investor of the Agreement do not and will not (a) violate the  memorandum or
articles of  association  of the  Investor or (b) assuming  compliance  with the
matters   referred  to  in  Section  3.4,  violate  any  applicable  law,  rule,
regulation,  judgment, injunction, order or decree except, in the case of clause
(b), to the extent that any such  violation  would not,  individually  or in the
aggregate, have a Material Adverse Effect.

            3.6 Financing. The Investor has, or will have prior to each Closing,
sufficient  cash,  available  lines of credit or other  sources  of  immediately
available funds to enable it to make payment of the Purchase Price and any other
amounts to be paid by it hereunder on such Closing.

            3.7 The  Investor (a) is domiciled  and has its  principal  place of
business  outside  the United  States,  (b) is not a U. S. Person (as defined in
Regulation S), and (c) was not formed for the purpose of investing in securities
not registered under the 1933 Act. As used herein, the "United States" means and
includes the United States of America,  its  territories  and  possessions,  any
state of the United  States,  and the District of  Columbia.

            3.8 At the time of offering to the Investor and communication of the
Investor's  order to  purchase  the  Shares  and at the  time of the  Investor's
execution of the


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<PAGE>

Agreement,  the persons acting on the Investor's behalf in connection  therewith
were located outside the United States.

            3.9 No offer to purchase the Shares was made in the United States.

            3.10  All  subsequent  offers  and sale of the  Shares  will be made
outside the United States in compliance  with Rule 903 or Rule 904 of Regulation
S , pursuant to  registration of the Shares under the 1933 Act or pursuant to an
exemption from such registration. The Investor understands the conditions of the
exemption  from  registration  afforded  by  Section  4(l) of the  1933  Act and
acknowledges that there can be no assurance that will it be able to rely on such
exemption.  In any case, the Investor will not resell the Shares  purchased at a
Closing to U.S.  Persons or within the United  States until after the end of the
ninety (90) day period  commencing  on the Closing  Date for such  Closing  (the
"Restricted Period").  This ninety (90) day period is a fifty (50) day extension
of the forty (40) day period set forth in Regulation S.

            3.11 The Investor has not and,  during the Restricted  Period,  will
not (a) enter into any long-put option, short call option or short position with
respect  to shares of Common  Stock or engage in any other  transaction  in such
shares or in options or other  derivative  securities  relating thereto which is
intended to hedge the  Investor's  ownership  position  in the  shares;  and (b)
directly  or  indirectly  use the  Shares  to cover  or  otherwise  satisfy  its
obligations under any put option,  call option or short position with respect to
shares of Common  Stock.

            3.12 The purchase and sale of securities, whether as principal or as
agent, is a regular part of the ordinary business of the Investor.

            3.13 The Investor is  purchasing  the Shares for its own account for
investment purposes and not with a view toward distribution.

            3.14 The Investor is not a  "distributor"  (as defined in Regulation
S) or a "dealer" (as defined in the 1933 Act).

            3.15 The Investor has made its own  investigation of the Company and
its business  prospects  and of the risks  associated  with an investment in the
Shares and acknowledges  that no  representation or warranty with respect to the
Company's  business  prospects has been made in the Agreement by or on behalf of
the Company.

            3.16 In the event of  resale of the  Shares  during  the  Restricted
Period,  the Investor (a) shall provide  written  confirmation  or other written
notice to any distributor,  dealer or person receiving a selling concession, fee
or other  remuneration  with respect to the Shares stating that such  subsequent
purchaser is subject to the same  restrictions on offers and sales that apply to
the Investor,  and (b) shall require that any such  subsequent  purchaser  shall
provide  such  written  confirmation  or other  notice  upon  resale  during the
Restricted Period.

            3.17 Confidentiality.  The Investor hereby represents,  warrants and
covenants that it shall  maintain in  confidence,  and shall not use or disclose
without the prior written consent of the Company, any information  identified as
confidential  that is  furnished  to it by the  Company in  connection  with the
Agreement.  This obligation of confidentiality  shall not apply, however, to any
information (a) in the public domain through no  unauthorized  act or failure to
act by the Investor,  or (b) lawfully disclosed to the Investor by a third party
who possessed such information  without any obligation of  confidentiality.  The
Investor  further  covenants  that it shall

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<PAGE>

return to the Company all tangible  materials  containing such  information upon
request by the Company.  The Investor agrees that it will restrict access to the
Company's confidential  information among its officers,  directors and employees
to those persons with a need to use such information.

         4. Mutual Condition to each Closing.  The obligations of the Company to
sell,  and the Investor to purchase,  the Shares  under the  Agreement  are each
subject to the  satisfaction  or, to the extent legally  permissible,  waiver by
each such party at or prior to each Closing of the following condition:

            4.1 No  Prohibition.  There  shall not then be in  effect  any order
enjoining or restraining the  transactions  contemplated by the Agreement or the
License and  Collaboration  Agreement  and there shall not then be instituted or
pending  any  action  or  proceeding  before  any  federal  or  state  court  or
governmental   agency  or  other   regulatory   or   administrative   agency  or
instrumentality (a) challenging the acquisition of the Shares by the Investor or
otherwise  seeking to  restrain  or prohibit  consummation  of the  transactions
contemplated  by the  Agreement  or the License and  Collaboration  Agreement or
seeking to impose any material limitations on any provisions of the Agreement or
the License and Collaboration  Agreement;  or (b) except as contemplated herein,
seeking to impose limitations on the Investor's ability  effectively to exercise
full rights of ownership of the Shares.

         5.  Conditions  of the  Investor's  Obligations  at each  Closing.  The
obligations  of the Investor  under  Section 1.1 of the Agreement are subject to
the  fulfillment on or before each Closing of each of the following  conditions,
the waiver of which shall not be effective if such  Investor does not consent in
writing thereto:

            5.1   Representations   and  Warranties.   The  representations  and
warranties of the Company contained in Section 2 shall be true on and as of such
Closing with the same effect as though such  representations  and warranties had
been made on and as of such Closing.

            5.2 Performance.  The Company shall have performed and complied with
all agreements,  obligations and conditions  contained in the Agreement that are
required  to be  performed  or  complied  with by the  Company on or before such
Closing.

            5.3 Compliance Certificate. The President or a Vice President of the
Company shall deliver to such Investor at such Closing a certificate  certifying
that the  conditions  specified in Sections 5.1 and 5.2 have been  fulfilled and
stating  that there has been no Material  Adverse  Effect  since June 30,  1995,
other than  because of operating  losses and changes in the  ordinary  course of
business.

            5.4  Secretary's  Certificate.  The  Secretary of the Company  shall
deliver to the Investor at such Closing a certificate  certifying  that attached
thereto are true and complete copies of each of the following documents:

            5.4.1 Restated Certificate of Incorporation,  and all amendments and
certificates of designation thereto as in effect on the applicable Closing Date,
of the Company;

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<PAGE>

            5.4.2  Bylaws,  as  amended as in effect on the  applicable  Closing
Date, of the Company; and

            5.4.3 Copies of the  resolutions of the Company's Board of Directors
authorizing  execution  and  delivery  of the  Agreement  and  the  License  and
Collaboration Agreement and performance of the transactions  contemplated herein
and therein.

         6.  Conditions  of the  Company's  Obligations  at  each  Closing.  The
obligations  of the Company to the Investor  under the  Agreement are subject to
the fulfillment on or before each Closing-of each of the following conditions by
the Investor:

            6.1   Representations   and  Warranties.   The  representations  and
warranties of the Investor contained in Section 3 hereof shall be true on and as
of such  Closing  with  the same  effect  as  though  such  representations  and
warranties had been made on and as of such Closing.

            6.2 Performance. The Investor shall have performed and complied with
all agreements,  obligations and conditions  contained in the Agreement that are
required  to be  performed  or complied  with by the  Investor on or before such
Closing.

            6.3 Bank of Thailand Approval. The Investor shall have received from
the Bank of  Thailand  and  delivered  to the  Company  a copy of,  the  written
approval for the remittance of the funds representing the Purchase Price for the
Shares purchased on such Closing.

            6.4 Compliance Certificate. The President or a Vice President of the
Investor shall deliver to Company at such Closing a certificate  certifying that
the  conditions  specified in Sections 6.1, 6.2 and 6.3 have been  fulfilled and
stating  that there has been no Material  Adverse  Effect  since June 30,  1995,
other than  because of operating  losses and changes in the  ordinary  course of
business.

            6.5 Officer's  Certificate.  A duly authorized  executive officer of
the Investor  shall deliver to Company at such Closing a certificate  certifying
that  attached  thereto are true and  complete  copies of each of the  following
documents:

            6.5.1  Memorandum of  Association  and the  affidavit  issued by the
Ministry  of  Commerce  as in  effect on the  applicable  Closing  Date,  of the
Investor;

            6.5.2  Articles  of  Association,  as  amended  as in  effect on the
applicable Closing Date, of the Investor; and

            6.5.3 Copies of the resolutions of the Investor's Board of Directors
authorizing  execution  and  delivery  of the  Agreement  and  the  License  and
Collaboration Agreement and performance of the transactions  contemplated herein
and therein.

            6.6  Additional  Conditions.  The  Investor  shall  have  made  such
additional   representations   and  warranties  and  satisfied  such  additional
conditions precedent, and shall agree to such additional post-closing covenants,
as  reasonably  requested  by the Company  upon  advice of its legal  counsel to
comply  with  amendments  by the  applicable  governmental  authorities  to,  or

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<PAGE>

interpretations by the applicable governmental  authorities of, Regulation S (or
its successor) after the date of the Agreement.

         7. Termination.

            7.1 Grounds for Termination.  The Agreement may be terminated at any
time prior to the Third Closing Date:

            7.1.1 by mutual written agreement of the Company and the Investor;

            7.1.2 by either  the  Company or the  Investor  if the  License  and
Collaboration Agreement expires or is terminated for any reason; or

            7.1.3 by either the  Company or the  Investor  if there shall be any
applicable  law or  regulation  that  makes  consummation  of  the  transactions
contemplated  hereby illegal or otherwise  prohibited or if  consummation of the
transactions  contemplated  hereby would violate any nonappealable  final order,
decree  or  judgment  of  any  court  or  governmental   body  having  competent
jurisdiction.

            The party  desiring to terminate the Agreement  shall give notice of
such termination to the other party.

            7.2  Effect  of  Termination.  If the  Agreement  is  terminated  as
permitted by Section 7.1, termination shall be without liability of either party
(or  any  stockholder,   director,   officer,  employee,  agent,  consultant  or
representative of such party) to the other party to the Agreement; provided that
if such  termination  shall  result from the willful  failure of either party to
fulfill a condition to the  performance  of the  obligations of the other party,
failure to perform a covenant of the  Agreement or breach by either party hereto
of any  representation  or warranty or agreement  contained  herein,  such party
shall be fully liable for any and all damages  incurred or suffered by the other
party as a result of such failure or breach. The provisions of Sections 3.17 and
8.6 shall survive any termination hereof.

            8. Miscellaneous.

            8.1  Successors  and  Assigns.  The  terms  and  conditions  of  the
Agreement  shall  inure to the  benefit  of and be binding  upon the  respective
permitted  successors  and  assigns of the  parties.  Nothing in the  Agreement,
express or implied,  is intended to confer upon any party other than the parties
hereto  or  their  respective  successors  and  assigns  any  rights,  remedies,
obligations,  or  liabilities  under or by  reason of the  Agreement,  except as
expressly provided in the Agreement.

            8.2 Governing Law. The Agreement  shall be governed by and construed
in accordance  with the laws of the State of  California,  without regard to the
conflicts of law principles  thereof.  If a party  initiates any legal action or
other  proceeding for the  enforcement or  interpretation  of the Agreement,  or
because of a dispute  or an  alleged  default,  breach or  misrepresentation  in
connection  with the  Agreement  or the  rights or  obligations  of the  parties
hereunder,  the parties  consent to the exclusive  personal  jurisdiction of the
appropriate state or federal court located in San Francisco,  California,  U. S.
A., in such action or other proceeding.

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<PAGE>

            8.3  Counterparts.  The  Agreement  may be  executed  in two or more
counterparts,  each of  which  shall be  deemed  an  original,  but all of which
together shall constitute one and the same instrument.

            8.4 Titles and  Subtitles.  The  titles  and  subtitles  used in the
Agreement  are  used  for  convenience  only  and  are not to be  considered  in
construing or interpreting the Agreement.

            8.5 Notices. Any consent,  notice or report required or permitted to
be or made  under the  Agreement  by a party to the other  shall be in  writing,
delivered  personally  or by  facsimile  (and  promptly  confirmed  by  personal
delivery,  air  mail  or   internationally-recognized   courier),  air  mail  or
internationally-recognized   courier,   postage   prepaid  (where   applicable),
addressed to the 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 the  Agreement)  shall be  effective  upon
receipt by the addressee.

If to
the Company:                        The Immune Response Corporation
                                    5935 Darwin Court
                                    Carlsbad, California 92008, U. S. A.
                                    Attention: Dennis J. Carlo, Ph. D.

with a copy to:                     Pillsbury Madison &Sutro
                                    235 Montgomery Street, 15th Floor
                                    San Francisco, California 94104, U.S.A.
                                    Attention: Thomas E. Sparks, Jr.

If to
the Investor:                       Trinity Medical Group, Co., Ltd.
                                    425/5 Silom No. 7
                                    Silom Road
                                    Bangkok 10500, Thailand
                                    Attention: Mr. Arun Churdboonchart

            8.6 Finders' Fee. Each party  represents that it neither is nor will
be  obligated  for any  finders'  fee or  commission  in  connection  with  this
transaction. The Investor agrees to indemnify and hold harmless the Company from
any liability for any commission or compensation in the nature of a finders' fee
(and the costs and  expenses of  defending  against  such  liability or asserted
liability) for which the Investor or any of its officers, partners, employees or
representatives is responsible.

            The Company  agrees to indemnify and hold harmless the Investor from
any liability for any commission or compensation in the nature of a finders' fee
(and the costs and  expenses of  defending  against  such  liability or asserted
liability)  for  which  the  Company  or  any  of  its  officers,  employees  or
representatives is responsible.

            8.7 Expenses.  Irrespective of whether any Closing is effected,  the
Company and the Investor shall pay their respective costs and expenses  incurred
with respect to the

                                      -10-
<PAGE>

negotiation, execution, delivery and performance of the Agreement. If any action
at law or in  equity is  necessary  to  enforce  or  interpret  the terms of the
Agreement, the prevailing party shall be entitled to reasonable attorneys' fees,
costs and necessary  disbursements in addition to any other relief to which such
party may be entitled.

            8.8 Amendments and Waivers. Any term of the Agreement may be amended
and the observance of any term of the Agreement may be waived (either  generally
or in a particular instance and either retroactively or prospectively),  only by
the mutual written  consent of the Company and the Investor.  Any,  amendment or
waiver  effected in accordance  with this  paragraph  shall be binding upon each
holder of any securities  purchased under the Agreement at the time outstanding,
each future holder of all such securities, and the Company.

            8.9 Severability.  If one or more provisions of the Agreement are he
to e unenforceable  under  applicable law, such provision shall be excluded from
the Agreement and the balance of the Agreement  shall be  interpreted as if such
provision  were so excluded  and shall be  enforceable  in  accordance  with its
terms.

            8.10  Entire   Agreement.   The   Agreement   and  the  License  and
Collaboration Agreement, together with their respective exhibits, constitute the
entire  agreement  between the parties with respect to the subject matter hereof
and thereof and supersede all prior agreements and understandings, both oral and
written,  between the parties  with  respect to the  subject  matter  hereof and
thereof. No representation,  inducement,  promise,  understanding,  condition or
warranty  not set forth herein or therein has been made or relied upon by either
party hereto.  Neither the  Agreement  nor any  provision  hereof is intended to
confer  upon any Person  other than the  parties  hereto any rights or  remedies
hereunder.

          IN WITNESS WHEREOF,  the parties have executed the Agreement as of the
date first above written.

                                                 THE IMMUNE RESPONSE CORPORATION


                                                 By: /s/ Dennis J. Carlo
                                                    ----------------------------
                                                 Title:  President and CEO
                                                       -------------------------


                                                 TRINITY MEDICAL GROUP, CO., LTD


                                                 By: /s/ Arun Churdboonchart
                                                    ----------------------------
                                                 Title:  President and CEO
                                                       -------------------------


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