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                                                                  EXHIBIT 10.79

                              [COMPANY LETTERHEAD]



January 16, 2001

Mr. Emile Loria
31 rue du Dr Jean Arlaud
31500 Toulouse, France


RE: EMPLOYMENT TERMS

Dear Emile:

EPIMMUNE INC. (the "Company") is pleased to offer you the position of President
and Chief Executive Officer, pursuant to the terms of this letter agreement
("Agreement") and contingent upon obtaining satisfactory approval of your right
to work in the United States.

1.      BOARD OF DIRECTORS

The Company agrees that it will nominate you as a member of the Board of
Directors and recommend that you be elected as a member of the Board of
Directors following your acceptance of this Agreement and prior to commencement
of employment with the Company. In the event, however, that you are unable for
any reason to commence employment within six (6) months of the date of this
Agreement, you agree that you shall immediately resign your position as a member
of the Board of Directors.

2.      DUTIES

Upon commencement of employment, you will be expected to do and perform all
services, acts or things necessary or advisable to manage and conduct the
business of the Company, including those duties normally associated with the
position of President and Chief Executive Officer. You will report to the
Company's Board of Directors, unless otherwise assigned by the Company. You will
work at our facility located in San Diego, California.

3.      BASE SALARY/BENEFITS

Upon commencement of employment, your base salary will be three hundred thousand
dollars (US$300,000) per year, less payroll deductions and all required
withholdings. Your base salary shall be prorated for any partial year of
employment on the basis of a 365-day fiscal year. You will be paid in regular
periodic payments in accordance with Company policy, but in no event less
frequent than semi-monthly. You will also be eligible for the standard Company
benefits, including medical insurance, vacation, sick leave and holidays.
Details about these benefit plans


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are available for your review. The Company may modify your compensation and
benefits from time to time as it deems necessary.

4.      LOYAL AND CONSCIENTIOUS PERFORMANCE

During your employment with the Company, you agree that you shall devote your
full business energies, interests, abilities and productive time to the proper
and efficient performance of your duties to the Company; provided that, you
shall not be precluded from engaging in civic, charitable or religious
activities or from serving on Boards of Directors of companies or organizations
which do not present any conflict of interest with the Company or effect your
performance of duties for the Company.

5.      BONUS

In addition to your base salary following commencement of employment, you will
be eligible to earn a performance bonus ("Bonus") equal to two percent (2%) of
any proceeds received by the Company from any public or private equity financing
completed by the Company during the first twelve (12) months of your employment.
In the event that you become eligible for this Bonus, you may elect to receive
the Bonus as either (i) a cash payment or (ii) a number of shares of the equity
security sold in the financing equal to the amount of the Bonus divided by the
per share price at which the equity was sold or (iii) any combination of cash
and stock you choose. Bonus payments will be awarded within a reasonable period
of time following the receipt of financing proceeds.

6.      RELOCATION

Upon commencement of employment, the Company agrees that it will provide you
with the following payments and reimbursements ("Relocation Benefits"):

        (a) Actual and reasonable cost of moving household goods from France to
San Diego, California;

        (b) Actual and reasonable temporary furnished living accommodations in
San Diego for up to six months;

        (c) Actual and reasonable automobile rental costs in San Diego for up to
six months;

        (d) Actual and reasonable cost of up to three trips for you and your
family to and from France as necessary to facilitate a smooth relocation
transition.

The Company also agrees that it will pay you US$60,000, less applicable
deductions and withholdings, to assist you with your relocation to San Diego,
California (the "Relocation Payment"). The Relocation Payment shall be a lump
sum payment that may be used by you in your sole discretion for expenses
associated with your move, including real estate brokerage fees and closing
costs. If you remain with the Company for twelve months from the date on which
your employment begins, you shall have no obligation to repay the Relocation
Payment. If you



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resign or the Company terminates you for Cause (as herein defined) within twelve
months of the date on which your employment begins, you agree to repay to the
Company 50% of the Relocation Payment. In the event that you become obligated to
repay 50% of the Relocation Payment, you agree that the Company may deduct such
amount from your final paycheck.

Reimbursements and payments to you under this section may be reported as
compensation to you and may be subject to state and/or federal taxation. If you
have questions regarding the tax implications, you should consult with your own
tax advisor.

7.      STOCK

Upon your election to the Board of Directors, the Company will sell to you, and
you agree to purchase, shares of common stock in an amount equal to 10% of the
outstanding shares of common stock on a fully diluted basis (including
conversion of Preferred Stock and exercise of currently outstanding Stock
Options), at a price equal to the fair market value of such stock on the date of
purchase (as determined by the closing price of such stock as reported on an
established stock exchange and as reported in The Wall Street Journal or such
other source as determined by the Board) (the "Shares"). The Shares shall be
subject to the terms of a restricted stock purchase agreement containing a
repurchase option in favor of the Company. The repurchase option will lapse
ratably each day over a four-year period beginning with your purchase date
provided that you remain in the continuous service of the Company. You agree to
pay for the Shares with a promissory note, secured by the Shares and payable in
four years from the date of purchase (the "Note"). With respect to each
indivisible share of stock under the Shares purchased with the proceeds of the
Note, you shall be personally liable for repayment of 50% of the amounts due
under the Note, and shall not be personally liable for repayment of the
remaining 50% of the amounts due under the Note. If you accept this Agreement,
you agree and understand that in connection with purchasing the Shares you will
be required to sign certain documents including, but not limited to, a
promissory note, stock pledge agreement, restricted stock purchase agreement,
joint escrow instructions and assignment separate from certificate.

8.      TERMINATION

The Company may terminate your employment at any time and for any or no reason,
with or without Cause (as defined herein) or advance notice by giving you
written notice of such termination. Similarly, you may terminate your employment
with the Company at any time at your election, in your sole discretion, for any
or no reason upon thirty (30) days notice to the Company, during which time you
shall provide reasonable transition assistance to the Company.

Notwithstanding the at-will nature of the employment relationship, if the
Company terminates your employment without Cause (as defined herein) or if you
resign from the Company for Good Reason (as defined herein), then upon your
furnishing to the Company an executed release and waiver of claims (a form of
which is attached hereto as Exhibit A): 1) you shall be entitled to receive
severance payments in the form of continuation of your base salary in effect at
the time of your termination, subject to standard payroll deductions and
withholdings, for twelve (12) months (the "Severance Period"). If you
voluntarily resign without Good Reason (as defined herein) or your employment is
terminated for Cause (as defined herein), all compensation and



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benefits will cease immediately and you will receive no additional payments from
the Company other than your accrued base salary and accrued and unused vacation
benefits earned through the date of your termination.

For purposes of this Agreement, "Cause" shall mean (i) willful misconduct by you
including, but not limited to, dishonesty which materially and adversely
reflects upon your ability to perform your duties for the Company, (ii) your
conviction of, or the entry of a pleading of guilty or nolo contendere by you
to, any crime involving moral turpitude or any felony, (iii) fraud, embezzlement
or theft against the Company, (iv) a material breach by you of any material
provision of the Proprietary Information and Inventions Agreement between you
and the Company (a copy of which is attached hereto as Exhibit B), or (v) your
willful and habitual failure to attend to your duties as assigned by the Board
of Directors or officers of the Company to whom you report and, in the case of
clauses (iv) and (v) above, which breach, misconduct or non-performance is not
cured by you within thirty (30) days after you receive written notice from the
Company of such breach, misconduct or non-performance.

For purposes of this Agreement, "Good Reason" shall mean termination by you of
your employment with the Company upon not less than thirty (30) days' prior
written notice to the Company (to allow the Company to remedy any basis for Good
Reason termination) as a result of (i) a substantial diminution in the scope of
your duties and authority within the Company which results in the assignment of
duties and responsibilities of materially lesser status, dignity and character
than your duties and responsibilities on the date of execution of this
Agreement, which is not the result of your failure to attend to and/or
successfully complete your duties and responsibilities, (ii) any reduction in
your base salary as initially set forth herein or as may be increased from time
to time, or (iii) relocation of your office, without your consent, to a location
that is more than thirty (30) miles from the Company's current corporate
headquarters.

9.      CHANGE IN CONTROL

If your employment is terminated by the Company or its successor Company without
Cause (as defined herein) or if you resign from the Company for Good Reason (as
defined herein) following a Change in Control (as defined herein), then upon
your furnishing to the Company an executed release and waiver of claims (a form
of which is attached hereto as Exhibit A): (i) the vesting of the Shares will be
immediately accelerated such that one hundred percent (100%) of the Shares will
be vested as of the Effective Date of the release and waiver attached hereto as
Exhibit A, and (ii) you will receive a lump sum payment equivalent to one year
of base salary, less applicable deductions and withholdings.

For purposes of this Agreement, "Change in Control" is defined as follows: (i) a
dissolution or liquidation of the Company; (ii) a sale or other disposition of
all or substantially all of the assets of the Company; (iii) a merger or
consolidation in which the Company is not the surviving corporation and in which
beneficial ownership of securities of the Company representing at least fifty
percent (50%) of the combined voting power entitled to vote in the election of
Directors has changed; (iv) an acquisition by any person, entity or group within
the meaning of Section 13(d) or 14(d) of the Securities Exchange Act, or any
comparable successor provisions (excluding any employee benefit plan, or related
trust, sponsored or maintained by the Company or subsidiary of



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the Company or other entity controlled by the Company) of the beneficial
ownership (within the meaning of Rule 13d-3 promulgated under the Exchange Act,
or comparable successor rule) of securities of the Company representing at least
fifty percent (50%) of the combined voting power entitled to vote in the
election of Directors.

In the event that any payments and other benefits provided for in this Agreement
or otherwise payable to you (the "Benefits") would (i) constitute "parachute
payments" within the meaning of Section 280G of the Internal Revenue Code of
1986, as amended (the "Code"), and (ii) but for this subsection would be subject
to the excise tax imposed by Section 4999 of the Code (the "Excise Tax"), then,
the Benefits to which you are entitled pursuant to this Agreement shall be
either:

        (a) Provided to you in full, or

        (b) Provided to you at such lesser extent that would result in no
portion of the Benefits being subject to the Excise Tax,

whichever of the foregoing amounts, when taking into account applicable federal,
state, local and foreign income and employment taxes, the Excise Tax, and any
other applicable taxes, results in the receipt by you, on an after tax basis, of
the greatest amount of the Benefits, notwithstanding that all or some portion of
the Benefits may be taxable under the Excise Tax. Unless you and the Company
otherwise agree in writing, any determination required under this subsection
shall be made in writing in good faith by an accountant selected by you. In the
event of a reduction of the Benefits under this Agreement, you shall be given
the choice of which of the Benefits to reduce. For purposes of making the
calculations required by this subsection, the accountant that you select may
make reasonable assumptions and approximations concerning applicable taxes and
may rely on reasonable, good faith interpretations concerning the application of
the Code, and other applicable legal authority. You and the Company shall
furnish your accountant such information and documents as he may reasonably
request in order to make a determination under this subsection.

Any payment and benefits received by you upon a Change in Control shall be in
lieu of any other severance payment to you, including the severance payment
provided in subsection 7 herein. In the event that you become entitled to
payment and benefits upon a Change in Control, the Company shall have no further
obligation to pay you any base salary, bonus or other compensation or benefits
under this Agreement, except for benefits due to you (or your dependents) under
the terms of your benefit plans.

10.     COMPANY POLICY

As a Company employee, you will be expected to abide by Company rules and
regulations and acknowledge in writing that you have read the Company's Employee
Handbook, which further will govern the terms and conditions of your employment.
The Company's Employee Handbook may be modified from time to time at the sole
discretion of the Company.

11.     PROPRIETARY INFORMATION AND INVENTIONS AGREEMENT

As a condition of employment, you will be required to sign and comply with the
Proprietary Information and Inventions Agreement attached hereto as Exhibit B,
which prohibits unauthorized use or disclosure of the Company's proprietary
information, among other things.



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In your work for the Company, you will be expected not to use or disclose any
confidential information, including trade secrets, of any former employer or
other person to whom you have an obligation of confidentiality. Rather, you will
be expected to use only that information which is generally known and used by
persons with training and experience comparable to your own, which is common
knowledge in the industry or otherwise legally in the public domain, or which is
otherwise provided or developed by the Company. During our discussions about
your proposed job duties, you assured us that you would be able to perform those
duties within the guidelines just described. Accordingly, you agree that you
will not bring onto Company premises any unpublished documents or property
belonging to any former employer or other person to whom you have an obligation
of confidentiality.

12.     ENTIRE AGREEMENT

This Agreement, together with your Proprietary Information and Inventions
Agreement and the stock documents referred to herein, forms the complete and
exclusive statement of the terms of your employment with the Company. The
employment terms in this Agreement supersede any other agreements or promises
made to you by anyone, whether oral or written.

13.     GOVERNING LAW

This Agreement will be governed by and construed according to the laws of the
State of California. You hereby expressly consent to the personal jurisdiction
of the state and federal courts located in San Diego, California for any lawsuit
filed there against you by the Company arising from or related to this
Agreement.

14.     SUCCESSORS AND ASSIGNS.

This Agreement will be binding upon your heirs, executors, administrators and
other legal representatives and will be for the benefit of the Company, its
successors, and its assigns.

As required by law, this offer is subject to satisfactory proof of your right to
work in the United States. Please sign and date this Agreement, and return it to
me by January 19, 2001, if you wish to accept employment with the Company under
the terms described above. If you accept our offer, we will expect you to
commence employment promptly upon receipt of authorization to work in the United
States. In the event that you are unable to begin work with the Company for any
reason after six (6) months from the date of the Agreement, the Agreement shall
become void and of no further force and effect, unless otherwise agreed to in
writing by you and the Company.




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We look forward to your favorable reply and to a productive and enjoyable work
relationship.

Sincerely,


/s/ Howard E. Greene, Jr.
----------------------------------
HOWARD E. GREENE, JR.
CHAIRMAN OF THE BOARD OF DIRECTORS


Accepted:


/s/ Emile Loria
----------------------------------
EMILE LORIA


January 16, 2001
----------------------------------
Date


Attachment:   Exhibit A:  Waiver and Release
              Exhibit B.  Proprietary Information and Inventions Agreement



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                                    EXHIBIT A

                          RELEASE AND WAIVER OF CLAIMS


        In consideration of the payments and other benefits set forth in the
Agreement dated ___________, to which this form is attached, I, EMILE LORIA,
hereby furnish EPIMMUNE INC. (the "Company"), with the following release and
waiver ("Release and Waiver").

        I hereby release, and forever discharge the Company, its officers,
directors, agents, employees, stockholders, successors, assigns affiliates and
Benefit Plans, of and from any and all claims, liabilities, demands, causes of
action, costs, expenses, attorneys' fees, damages, indemnities and obligations
of every kind and nature, in law, equity, or otherwise, known and unknown,
suspected and unsuspected, disclosed and undisclosed, arising at any time prior
to and including my employment Termination Date, including, but not limited to
any claims relating to my employment and the termination of my employment,
including but not limited to, claims pursuant to any federal, state or local law
relating to employment, including, but not limited to, discrimination claims,
claims under the California Fair Employment and Housing Act, and the Federal Age
Discrimination in Employment Act of 1967, as amended ("ADEA"), or claims for
wrongful termination, breach of the covenant of good faith, contract claims,
tort claims, and wage or benefit claims, including but not limited to, claims
for salary, bonuses, commissions, stock, stock options, vacation pay, fringe
benefits, severance pay or any form of compensation.

        I also acknowledge that I have read and understand Section 1542 of the
California Civil Code which reads as follows: "A GENERAL RELEASE DOES NOT EXTEND
TO CLAIMS WHICH THE CREDITOR DOES NOT KNOW OR SUSPECT TO EXIST IN HIS FAVOR AT
THE TIME OF EXECUTING THE RELEASE, WHICH IF KNOWN BY HIM MUST HAVE MATERIALLY
AFFECTED HIS SETTLEMENT WITH THE DEBTOR." I hereby expressly waive and
relinquish all rights and benefits under that section and any law of any
jurisdiction of similar effect with respect to any claims I may have against the
Company.

        I acknowledge that, among other rights, I am waiving and releasing any
rights I may have under ADEA, that this Release and Waiver is knowing and
voluntary, and that the consideration given for this Release and Waiver is in
addition to anything of value to which I was already entitled as an executive of
the Company. I further acknowledge that I have been advised, as required by the
Older Workers Benefit Protection Act, that: (a) the Release and Waiver granted
herein does not relate to claims which may arise after this Release and Waiver
is executed; (b) I have the right to consult with an attorney prior to executing
this Release and Waiver (although I may choose voluntarily not to do so); and if
I am over 40 years of age upon execution of this Release and Waiver: (c) I have
twenty-one (21) days from the date of termination of my employment with the
Company in which to consider this Release and Waiver (although I may choose
voluntarily to execute this Release and Waiver earlier); (d) I have seven (7)
days following the execution of this Release and Waiver to revoke my consent to
this Release and Waiver; and (e) this Release and Waiver shall not be effective
until the seven (7) day revocation period has expired.

Date:                                            By: /s/ Emile Loria
                                                     --------------------------
                                                     EMILE LORIA


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                                    EXHIBIT B

                                  EPIMMUNE INC.

            EMPLOYEE PROPRIETARY INFORMATION AND INVENTIONS AGREEMENT



        In consideration of my employment or continued employment by EPIMMUNE
INC. (the "Company"), and the compensation now and hereafter paid to me, I
hereby agree as follows:

1.      NONDISCLOSURE

        1.1 RECOGNITION OF COMPANY'S RIGHTS; NONDISCLOSURE. At all times during
my employment and thereafter, I will hold in strictest confidence and will not
disclose, use, lecture upon or publish any of the Company's Proprietary
Information (defined below), except as such disclosure, use or publication may
be required in connection with my work for the Company, or unless an officer of
the Company expressly authorizes such in writing. I will obtain Company's
written approval before publishing or submitting for publication any material
(written, verbal, or otherwise) that relates to my work at Company and/or
incorporates any Proprietary Information. I hereby assign to the Company any
rights I may have or acquire in such Proprietary Information and recognize that
all Proprietary Information shall be the sole property of the Company and its
assigns.

        1.2 PROPRIETARY INFORMATION. The term "PROPRIETARY INFORMATION" shall
mean any and all confidential and/or proprietary knowledge, data or information
of the Company. By way of illustration but not limitation, "PROPRIETARY
INFORMATION" includes (a) trade secrets, inventions, mask works, ideas,
processes, formulas, source and object codes, data, programs, other works of
authorship, know-how, improvements, discoveries, developments, designs and
techniques (hereinafter collectively referred to as "INVENTIONS"); and (b)
information regarding plans for research, development, new products, marketing
and selling, business plans, budgets and unpublished financial statements,
licenses, prices and costs, suppliers and customers; and (c) information
regarding the skills and compensation of other employees of the Company.
Notwithstanding the foregoing, it is understood that, at all such times, I am
free to use information which is generally known in the trade or industry, which
is not gained as result of a breach of this Agreement, and my own, skill,
knowledge, know-how and experience to whatever extent and in whichever way I
wish.

        1.3 THIRD PARTY INFORMATION. I understand, in addition, that the Company
has received and in the future will receive from third parties confidential or
proprietary information ("THIRD PARTY INFORMATION") subject to a duty on the
Company's part to maintain the confidentiality of such information and to use it
only for certain limited purposes. During the term of my employment and
thereafter, I will hold Third Party Information in the strictest confidence and
will not disclose to anyone (other than Company personnel who need to know such
information in connection with their work for the Company) or use, except in
connection with my work for the Company, Third Party Information unless
expressly authorized by an officer of the Company in writing.

        1.4 NO IMPROPER USE OF INFORMATION OF PRIOR EMPLOYERS AND OTHERS. During
my employment by the Company I will not improperly use or



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disclose any confidential information or trade secrets, if any, of any former
employer or any other person to whom I have an obligation of confidentiality,
and I will not bring onto the premises of the Company any unpublished documents
or any property belonging to any former employer or any other person to whom I
have an obligation of confidentiality unless consented to in writing by that
former employer or person. I will use in the performance of my duties only
information which is generally known and used by persons with training and
experience comparable to my own, which is common knowledge in the industry or
otherwise legally in the public domain, or which is otherwise provided or
developed by the Company.

2.      ASSIGNMENT OF INVENTIONS.

        2.1 PROPRIETARY RIGHTS. The term "PROPRIETARY RIGHTS" shall mean all
trade secret, patent, copyright, mask work and other intellectual property
rights throughout the world.

        2.2 PRIOR INVENTIONS. Inventions, if any, patented or unpatented, which
I made prior to the commencement of my employment with the Company are excluded
from the scope of this Agreement. To preclude any possible uncertainty, I have
set forth on Exhibit B (Previous Inventions) attached hereto a complete list of
all Inventions that I have, alone or jointly with others, conceived, developed
or reduced to practice or caused to be conceived, developed or reduced to
practice prior to the commencement of my employment with the Company, that I
consider to be my property or the property of third parties and that I wish to
have excluded from the scope of this Agreement (collectively referred to as
"PRIOR INVENTIONS"). If disclosure of any such Prior Invention would cause me to
violate any prior confidentiality agreement, I understand that I am not to list
such Prior Inventions in Exhibit B but am only to disclose a cursory name for
each such invention, a listing of the party(ies) to whom it belongs and the fact
that full disclosure as to such inventions has not been made for that reason. A
space is provided on Exhibit B for such purpose. If no such disclosure is
attached, I represent that there are no Prior Inventions. If, in the course of
my employment with the Company, I incorporate a Prior Invention into a Company
product, process or machine, the Company is hereby granted and shall have a
nonexclusive, royalty-free, irrevocable, perpetual, worldwide license (with
rights to sublicense through multiple tiers of sublicensees) to make, have made,
modify, use and sell such Prior Invention. Notwithstanding the foregoing, I
agree that I will not incorporate, or permit to be incorporated, Prior
Inventions in any Company Inventions without the Company's prior written
consent.

        2.3 ASSIGNMENT OF INVENTIONS. Subject to Sections 2.4, and 2.6, I hereby
assign and agree to assign in the future (when any such Inventions or
Proprietary Rights are first reduced to practice or first fixed in a tangible
medium, as applicable) to the Company all my right, title and interest in and to
any and all Inventions (and all Proprietary Rights with respect thereto) whether
or not patentable or registrable under copyright or similar statutes, made or
conceived or reduced to practice or learned by me, either alone or jointly with
others, during the period of my employment with the Company. Inventions assigned
to the Company, or to a third party as directed by the Company pursuant to this
Section 2, are hereinafter referred to as "COMPANY INVENTIONS."



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        2.4 NONASSIGNABLE INVENTIONS. This Agreement does not apply to an
Invention which qualifies fully as a nonassignable Invention under Section 2870
of the California Labor Code (hereinafter "SECTION 2870"). I have reviewed the
notification on Exhibit A (Limited Exclusion Notification) and agree that my
signature acknowledges receipt of the notification.

        2.5 OBLIGATION TO KEEP COMPANY INFORMED. During the period of my
employment and for six (6) months after termination of my employment with the
Company, I will promptly disclose to the Company fully and in writing all
Inventions authored, conceived or reduced to practice by me, either alone or
jointly with others. In addition, I will promptly disclose to the Company all
patent applications filed by me or on my behalf within a year after termination
of employment. At the time of each such disclosure, I will advise the Company in
writing of any Inventions that I believe fully qualify for protection under
Section 2870; and I will at that time provide to the Company in writing all
evidence necessary to substantiate that belief. The Company will keep in
confidence and will not use for any purpose or disclose to third parties without
my consent any confidential information disclosed in writing to the Company
pursuant to this Agreement relating to Inventions that qualify fully for
protection under the provisions of Section 2870. I will preserve the
confidentiality of any Invention that does not fully qualify for protection
under Section 2870.

        2.6 GOVERNMENT OR THIRD PARTY. I also agree to assign all my right,
title and interest in and to any particular Company Invention to a third party,
including without limitation the United States, as directed by the Company.

        2.7 WORKS FOR HIRE. I acknowledge that all original works of authorship
which are made by me (solely or jointly with others) within the scope of my
employment and which are protectable by copyright are "works made for hire,"
pursuant to United States Copyright Act (17 U.S.C., Section 101).

        2.8 ENFORCEMENT OF PROPRIETARY RIGHTS. I will assist the Company in
every proper way to obtain, and from time to time enforce, United States and
foreign Proprietary Rights relating to Company Inventions in any and all
countries. To that end I will execute, verify and deliver such documents and
perform such other acts (including appearances as a witness) as the Company may
reasonably request for use in applying for, obtaining, perfecting, evidencing,
sustaining and enforcing such Proprietary Rights and the assignment thereof. In
addition, I will execute, verify and deliver assignments of such Proprietary
Rights to the Company or its designee. My obligation to assist the Company with
respect to Proprietary Rights relating to such Company Inventions in any and all
countries shall continue beyond the termination of my employment, but the
Company shall compensate me at a reasonable rate after my termination for the
time actually spent by me at the Company's request on such assistance.

In the event the Company is unable for any reason, after reasonable effort, to
secure my signature on any document needed in connection with the actions
specified in the preceding paragraph, I hereby irrevocably designate and appoint
the Company and its duly authorized officers and agents as my agent and attorney
in fact, which appointment is coupled with an interest, to act for and in my
behalf to execute, verify and file any such documents and to do all other
lawfully permitted acts to further the purposes of the



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preceding paragraph with the same legal force and effect as if executed by me. I
hereby waive and quitclaim to the Company any and all claims, of any nature
whatsoever, which I now or may hereafter have for infringement of any
Proprietary Rights assigned hereunder to the Company.

        3. RECORDS. I agree to keep and maintain adequate and current records
(in the form of notes, sketches, drawings and in any other form that may be
required by the Company) of all Proprietary Information developed by me and all
Inventions made by me during the period of my employment at the Company, which
records shall be available to and remain the sole property of the Company at all
times.

        4. ADDITIONAL ACTIVITIES. I agree that during the period of my
employment by the Company I will not, without the Company's express written
consent, engage in any employment or business activity which is competitive
with, or would otherwise conflict with, my employment by the Company. I agree
further that for the period of my employment by the Company and for one (l) year
after the date of termination of my employment by the Company I will not induce
any employee of the Company to leave the employ of the Company.

        5. NO CONFLICTING OBLIGATION. I represent that my performance of all the
terms of this Agreement and as an employee of the Company does not and will not
breach any agreement to keep in confidence information acquired by me in
confidence or in trust prior to my employment by the Company. I have not entered
into, and I agree I will not enter into, any agreement either written or oral in
conflict herewith.

        6. RETURN OF COMPANY DOCUMENTS. When I leave the employ of the Company,
I will deliver to the Company any and all drawings, notes, memoranda,
specifications, devices, formulas, and documents, together with all copies
thereof, and any other material containing or disclosing any Company Inventions,
Third Party Information or Proprietary Information of the Company. I further
agree that any property situated on the Company's premises and owned by the
Company, including disks and other storage media, filing cabinets or other work
areas, is subject to inspection by Company personnel at any time with or without
notice. Prior to leaving, I will cooperate with the Company in completing and
signing the Company's termination statement.

        7. LEGAL AND EQUITABLE REMEDIES. Because my services are personal and
unique and because I may have access to and become acquainted with the
Proprietary Information of the Company, the Company shall have the right to
enforce this Agreement and any of its provisions by injunction, specific
performance or other equitable relief, without bond and without prejudice to any
other rights and remedies that the Company may have for a breach of this
Agreement.

        8. NOTICES. Any notices required or permitted hereunder shall be given
to the appropriate party at the address specified below or at such other address
as the party shall specify in writing. Such notice shall be deemed given upon
personal delivery to the appropriate address or if sent by certified or
registered mail, three (3) days after the date of mailing.

        9. NOTIFICATION OF NEW EMPLOYER. In the event that I leave the employ of
the Company, I hereby consent to the notification of my new employer of my
rights and obligations under this Agreement.



                                       4
<PAGE>   13

10.        GENERAL PROVISIONS.

           10.1 GOVERNING LAW; CONSENT TO PERSONAL JURISDICTION. This Agreement
will be governed by and construed according to the laws of the State of
California, as such laws are applied to agreements entered into and to be
performed entirely within California between California residents. I hereby
expressly consent to the personal jurisdiction of the state and federal courts
located in San Diego County, California for any lawsuit filed there against me
by Company arising from or related to this Agreement.

           10.2 SEVERABILITY. In case any one or more of the provisions
contained in this Agreement shall, for any reason, be held to be invalid,
illegal or unenforceable in any respect, such invalidity, illegality or
unenforceability shall not affect the other provisions of this Agreement, and
this Agreement shall be construed as if such invalid, illegal or unenforceable
provision had never been contained herein. If moreover, any one or more of the
provisions contained in this Agreement shall for any reason be held to be
excessively broad as to duration, geographical scope, activity or subject, it
shall be construed by limiting and reducing it, so as to be enforceable to the
extent compatible with the applicable law as it shall then appear.

           10.3 SUCCESSORS AND ASSIGNS. This Agreement will be binding upon my
heirs, executors, administrators and other legal representatives and will be for
the benefit of the Company, its successors, and its assigns.

           10.4 SURVIVAL. The provisions of this Agreement shall survive the
termination of my employment and the assignment of this Agreement by the Company
to any successor in interest or other assignee.

           10.5 EMPLOYMENT. I agree and understand that nothing in this
Agreement shall confer any right with respect to continuation of employment by
the Company, nor shall it interfere in any way with my right or the Company's
right to terminate my employment at any time, with or without cause.

           10.6 WAIVER. No waiver by the Company of any breach of this Agreement
shall be a waiver of any preceding or succeeding breach. No waiver by the
Company of any right under this Agreement shall be construed as a waiver of any
other right. The Company shall not be required to give notice to enforce strict
adherence to all terms of this Agreement.

           10.7 ENTIRE AGREEMENT. The obligations pursuant to Sections 1 and 2
of this Agreement shall apply to any time during which I was previously
employed, or am in the future employed, by the Company as a consultant if no
other agreement governs nondisclosure and assignment of inventions during such
period. This Agreement is the final, complete and exclusive agreement of the
parties with respect to the subject matter hereof and supersedes and merges all
prior discussions between us. No modification of or amendment to this Agreement,
nor any waiver of any rights under this Agreement, will be effective unless in
writing and signed by the party to be charged. Any subsequent change or changes
in my duties, salary or compensation will not affect the validity or scope of
this Agreement.

        This Agreement shall be effective as of the first day of my employment
with the Company, namely: _______________, 20__.




                                       5
<PAGE>   14

        I HAVE READ THIS AGREEMENT CAREFULLY AND UNDERSTAND ITS TERMS. I HAVE
COMPLETELY FILLED OUT EXHIBIT B TO THIS AGREEMENT.



Date: January 16, 2001
      --------------------------


/s/ Emile Loria
--------------------------------
(SIGNATURE)


Emile Loria
--------------------------------
(PRINTED NAME)


ACCEPTED AND AGREED TO:



EPIMMUNE INC.


By: /s/ Robert De Vaere
    ----------------------------

--------------------------------
Title:


--------------------------------
(Address)


--------------------------------
Dated:


--------------------------------
January 16, 2001



                                       6
<PAGE>   15

                                    EXHIBIT A

                         LIMITED EXCLUSION NOTIFICATION



        THIS IS TO NOTIFY you in accordance with Section 2872 of the California
Labor Code that the foregoing Agreement between you and the Company does not
require you to assign or offer to assign to the Company any invention that you
developed entirely on your own time without using the Company's equipment,
supplies, facilities or trade secret information except for those inventions
that either:

        1. Relate at the time of conception or reduction to practice of the
invention to the Company's business, or actual or demonstrably anticipated
research or development of the Company;

        2. Result from any work performed by you for the Company.

           To the extent a provision in the foregoing Agreement purports to
require you to assign an invention otherwise excluded from the preceding
paragraph, the provision is against the public policy of this state and is
unenforceable.

           This limited exclusion does not apply to any patent or invention
covered by a contract between the Company and the United States or any of its
agencies requiring full title to such patent or invention to be in the United
States.

        I ACKNOWLEDGE RECEIPT of a copy of this notification.


                                           By: /s/ Emile Loria
                                               --------------------------------
                                               (PRINTED NAME OF EMPLOYEE)


                                           Date:
                                                -------------------------------



WITNESSED BY:



-----------------------------------
(PRINTED NAME OF REPRESENTATIVE)


<PAGE>   16

                                    EXHIBIT B


TO:      EPIMMUNE INC.

FROM:    EMILE LORIA

DATE:
         --------------------

SUBJECT: PREVIOUS INVENTIONS


        1. Except as listed in Section 2 below, the following is a complete list
of all inventions or improvements relevant to the subject matter of my
employment by EPIMMUNE INC. (the "COMPANY") that have been made or conceived or
first reduced to practice by me alone or jointly with others prior to my
engagement by the Company:

        [ ]   No inventions or improvements.

        [ ]   See below:


              ------------------------------------------------------------------

              ------------------------------------------------------------------

              ------------------------------------------------------------------

        [ ]   Additional sheets attached.

        2. Due to a prior confidentiality agreement, I cannot complete the
disclosure under Section 1 above with respect to inventions or improvements
generally listed below, the proprietary rights and duty of confidentiality with
respect to which I owe to the following party(ies):


<TABLE>
<CAPTION>
       INVENTION OR IMPROVEMENT            PARTY(IES)            RELATIONSHIP
<S>                                        <C>                  <C>
1.
       ------------------------            ----------            ------------

2.
       ------------------------            ----------            ------------

3.
       ------------------------            ----------            ------------
</TABLE>


[ ]     Additional sheets attached.



                                        2