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                                                                 Exhibit 10.15

                              EMPLOYMENT AGREEMENT

                  This Employment Agreement (the "Agreement") is entered into
by and between Versicor Inc., a Delaware corporation (the "Company"), and
Dinesh V. Patel, Ph.D. (the "Executive"), as of the 28th day of July 2000.

                  WHEREAS, the Board of Directors of the Company (the
"Board") has determined that it is in the best interests of the Company and
its stockholders to assure that the Company will have the continued service
of the Executive, and the Board therefore desires to provide the Executive
with compensation and benefits arrangements that satisfy the expectations of
the Executive and that are competitive with those of other corporations; and

                  WHEREAS, the Board also desires to assure that the
Executive's services will be available notwithstanding the possibility,
threat or occurrence of a Change of Control (as defined below) of the
Company, and the Board believes it is imperative to diminish the inevitable
distraction of the Executive by virtue of the personal uncertainties and
risks created by a pending or threatened Change of Control and to encourage
the Executive's full attention and dedication to the Company in the event of
any threatened or pending Change of Control.

                  NOW, THEREFORE, for good and valuable consideration, the
receipt and sufficiency of which is hereby acknowledged, the parties hereto,
intending to be legally bound, do hereby agree as follows:

I.       EMPLOYMENT PERIOD.

                  The Company hereby agrees to continue the Executive in its
employ, and the Executive hereby agrees to remain in the employ of the
Company subject to the terms and conditions of this Agreement, for the period
commencing on the date the Securities and Exchange Commission declares
effective the Company's Form S-1 ("Effective Date") and ending on the third
anniversary of such date (the "Employment Period"); provided, however, that
commencing on the date one year after the Effective Date, and on each annual
anniversary of the Effective Date (such date and each annual anniversary
thereof shall be hereinafter referred to as the "Renewal Date"), unless
previously terminated, the Employment Period shall be automatically extended
so as to terminate three years from such Renewal Date, unless at least 60
days prior to the Renewal Date the Company shall give notice to the Executive
that the Employment Period shall not be so extended.

II.      DUTIES.

                  A.       During the Employment Period, the Executive shall
serve as Vice President, Drug Discovery of the Company, and shall have such
other duties and responsibilities as the Board of Directors of the Company
shall determine from time to time.

                  B.       During the Employment Period, the Executive agrees
to devote substantially all of his time, energy and ability to the business
of the Company. Nothing herein shall prevent the Executive, upon approval of
the Board of Directors of the Company, from serving as a director or trustee
of other corporations or businesses that are not in competition

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with the business of the Company or in competition with any present or future
affiliate of the Company, provided such service does not materially interfere
with the Executive's duties hereunder.

III.     COMPENSATION.

                  A.       BASE SALARY. The Company will pay to the Executive
a base salary at the rate of $205,119 per year. Such salary shall be earned
monthly and shall be payable in periodic installments no less frequently than
monthly in accordance with the Company's customary practices. Amounts payable
shall be reduced by standard withholding and other authorized deductions. The
Company will review the Executive's salary at least annually. The Company may
in its discretion increase the Executive's salary but it may not reduce it
during the term of this Agreement. Any increase in the Executive's salary
shall not serve to limit or reduce any other obligation to the Executive
under this Agreement.

                  B.       ANNUAL BONUS, INCENTIVE, SAVINGS AND RETIREMENT
PLANS. The Executive shall be entitled to participate in all annual bonus,
incentive, stock incentive, savings and retirement plans, defined
contribution plans, practices, policies and programs applicable generally to
other executives of the Company.

                  C.       WELFARE BENEFIT PLANS. The Executive and/or his
family, as the case may be, shall be eligible for participation in and shall
receive all benefits under welfare benefit plans, practices, policies and
programs provided by the Company (including, without limitation, medical,
prescription, dental, disability, salary continuance, executive life, group
life, accidental death and travel accident insurance plans and programs) to
the extent such plan, practices, and programs are applicable generally to
executives of the Company.

                  D.       EXPENSES. The Executive shall be entitled to
receive prompt reimbursement for all reasonable employment expenses incurred
by him in accordance with the policies, practices and procedures as in effect
generally with respect to other executives of the Company.

                  E.       FRINGE BENEFITS. The Executive shall be entitled
to fringe benefits in accordance with the plans, practices, programs and
policies as in effect generally with respect to other executives of the
Company.

                  F.       VACATION. The Executive shall be entitled to paid
vacation time in accordance with the plans, policies, programs and practices
as in effect with respect to other executives of the Company.

                  G.       PLAN AMENDMENTS. The Company reserves the right to
modify, suspend or discontinue any and all of its executive plans, practices,
policies and programs at any time without recourse by the Executive so long
as such action is taken generally with respect to other similarly situated
executives and does not single out the Executive.

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IV.      TERMINATION.

                  A.       DEATH OR DISABILITY. The Executive's employment
shall terminate automatically upon the Executive's death. If the Company
determines in good faith that a Disability of the Executive has occurred (as
Disability is defined below), it may give to the Executive written notice in
accordance with Section XIV of its intention to terminate the Executive's
employment. In such event, the Executive's employment with the Company shall
terminate effective on the 30th day after receipt of such notice by the
Executive (the "Disability Effective Date"), provided that, within the 30
days after such receipt, the Executive shall not have returned to full-time
performance of his duties. For purposes of this Agreement, "Disability" shall
mean the absence of the Executive from his duties with the Company on a
full-time basis (1) for a period of three consecutive months as a result of
incapacity due to mental or physical illness that is determined to be total
and permanent by a physician selected by the Company or its insurers and
acceptable to the Executive or his legal representative (such agreement as to
acceptability not to be withheld unreasonably) or (2) for shorter periods
aggregating 180 or more business days in any twelve (12) month period.
"Incapacity" as used herein shall be limited only to such Disability which
substantially prevents the Company from availing itself of the services of
the Executive or substantially impairs the Executive's ability to perform
services to the standard reasonably expected by the Company for the
Executive's office.

                  B.       CAUSE, ETC. The Company also may at any time,
before or after a Change in Control, terminate the Executive's employment for
"Cause." For purposes of this Agreement, "Cause" shall mean that the Company,
acting in good faith based upon the information then known to the Company,
determines that the Executive has: (1) repeatedly failed to perform in a
material respect his obligations under the Agreement without proper reason
and has not cured such failure in a reasonable time after receiving notice
from the Company, (2) willfully engaged in illegal conduct or gross
misconduct that is materially injurious to the Company, or (3) breached the
provisions of Section VI (Confidential Information) of this Agreement.
Section VI will continue in effect in the event that the Executive's
employment is terminated for Cause.

                  For purposes of this provision, no act or failure to act,
on the part of the Executive, shall be considered "willful" unless it is
done, or omitted to be done, by the Executive in bad faith or without
reasonable belief that the Executive's action or omission was in the best
interests of the Company. Any act, or failure to act, based upon authority
given pursuant to a resolution duly adopted by the Board or upon the
instructions of the Chief Executive Officer or a senior officer of the
Company or based upon the advice of counsel for the Company shall be
conclusively presumed to be done, or omitted to be done, by the Executive in
good faith and in the best interests of the Company. No termination of the
Executive for Cause will be effective unless adopted pursuant to a resolution
duly adopted by the affirmative vote of not less than a majority of the
entire membership of the Board at a meeting of the Board called and held for
such purpose, and communicated to the Executive by written notice that
explains the basis on which Cause has been found.

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                  C.       OBLIGATIONS OF THE COMPANY UPON TERMINATION.

                  1.       DEATH OR DISABILITY. If the Executive's employment
is terminated by reason of the Executive's Death or Disability, this
Agreement shall not be subject to any further extension pursuant to Section I
hereof.

                  2.       CAUSE, ETC. If the Executive's employment is
terminated by the Company pursuant to Section IV-B, this Agreement shall
terminate without further obligations to the Executive other than for (a)
payment of the sum of the Executive's annual base salary through the date of
termination and any accrued vacation pay to the extent not theretofore paid,
which shall be paid to the Executive or his estate or beneficiary, as
applicable, in a lump sum in cash within 30 days of the Date of Termination;
(b) payment of any compensation previously earned and deferred by the
Executive (together with any accrued interest or earnings thereon), which
shall be paid to the Executive or his estate or beneficiary at the times
provided in, and pursuant to terms of, the plan or agreement under which such
compensation was deferred; and (c) payment to the Executive or his estate or
beneficiary, as applicable, any amounts due pursuant to the terms of any
applicable welfare benefit plans. The payments described in clauses (a) and
(b) shall hereinafter be referred to as the "Accrued Obligations." If it is
subsequently determined that the Company did not have the right to terminate
the Executive under Section IV-B, then the Company's decision to terminate
shall be deemed to have been made under Section IV-C-3 and the amounts
payable thereunder shall be the only amounts the Executive may receive for
his termination.

                  3.       OTHER. If the Company breaches this Agreement by
terminating the Executive's employment other than pursuant to Sections IV-A
or IV-B, the Company shall pay to the Executive by cashier's check
immediately upon the Executive's termination of employment with the Company
an amount equal to three times the sum of (1) the amount of the highest
annual base salary paid to the Executive during the three most recent
calendar years ending prior to the year in which the Change in Control occurs
and (2) the amount of the highest bonus (or bonuses) paid to the Executive
for any calendar year ending prior to the year in which the Change in Control
occurs. This payment shall be in addition to the timely payment of the
Accrued Obligations. The Executive shall have no duty to mitigate damages and
none of the payments provided in this Section IV-C-3 shall be reduced by any
amounts earned or received by Executive from a third party at any time.

                  4.       EXCLUSIVE REMEDY. The Executive agrees that the
payments contemplated by this Agreement shall constitute the exclusive and
sole remedy for any termination of his employment and the Executive covenants
not to assert or pursue any other remedies, at law or in equity, with respect
to any termination of employment.

                  D.       NOTICE OF TERMINATION. Any termination by the
Company for Cause, or by the Executive for Good Reason, shall be communicated
by Notice of Termination to the other party hereto given in accordance with
Section XIV of this Agreement. For purposes of this Agreement, a "Notice of
Termination" means a written notice which (1) indicates the specific
termination provision in this Agreement relied upon, (2) to the extent
applicable, sets forth in reasonable detail the facts and circumstances
claimed to provide a basis for termination of the Executive's employment
under the provision so indicated and (3) if the Date of Termination (as

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defined below) is other than the date of receipt of such notice, specifies
the termination date (which date shall be not more than thirty days after the
giving of such notice). The failure by the Executive or the Company to set
forth in the Notice of Termination any fact or circumstance which contributes
to a showing of Good Reason or Cause shall not waive any right of the
Executive or the Company, respectively, hereunder or preclude the Executive
or the Company, respectively, from asserting such fact or circumstance in
enforcing the Executive's or the Company's rights hereunder.

                  E.       DATE OF TERMINATION. "Date of Termination" means
(1) if the Executive's employment is terminated by the Company for Cause, or
by the Executive for Good Reason, the date of receipt of the Notice of
Termination or any later date specified therein, as the case may be, (2) if
the Executive's employment is terminated by the Company other than for Cause
or Disability, the Date of Termination shall be the date on which the Company
notifies the Executive of such termination and (3) if the Executive's
employment is terminated by reason of Death or Disability, the Date of
Termination shall be the date of death of the Executive or the Disability
Effective Date, as the case may be.

V.       CHANGE IN CONTROL.

                  A.       CHANGE OF CONTROL PAYMENTS. Notwithstanding
anything to the contrary in this Agreement, if a Change in Control (as
defined below) of the Company occurs during the term of this Agreement, and
if within two years following such Change in Control either the Company
terminates the Executive's employment without Cause, or if the Executive
terminates his employment for Good Reason (as defined below), the Company
shall pay to the Executive by cashier's check immediately upon the
Executive's termination of employment with the Company an amount equal to two
times the sum of (1) the amount of the highest annual base salary paid to the
Executive during the two most recent calendar years ending prior to the year
in which the Change in Control occurs and (2) the amount of the highest bonus
(or bonuses) paid to the Executive for any calendar year ending prior to the
year in which the Change in Control occurs. This payment shall be in lieu of
the payment otherwise payable under Section IV-C-3(a), but shall be in
addition to the timely payment of the Accrued Obligations. In addition, the
Company shall continue to provide all benefits under the welfare benefit
plans as set forth in Section III-C until the earlier of (1) the Executive's
receipt of benefits substantially similar in scope and nature from another
employer or (2) three years after the most recent Renewal Date. The Executive
shall have no duty to mitigate damages and none of the payments provided in
this Section V-A shall be reduced by any amounts earned or received by the
Executive from a third party at any time. Notwithstanding anything to the
contrary in this Section V, if, in connection with a Change in Control
transaction, the Executive voluntarily enters a new written employment
agreement with the Company or its successor, the Executive may no longer rely
upon the provisions of this Section V.

                  B.       CERTAIN ADDITIONAL PAYMENTS.

                  1.       Notwithstanding anything in this Agreement to the
contrary and except as set forth below, in the event it shall be determined
that any payment or distribution by the Company or its affiliates to or for
the benefit of the Executive (whether paid or payable or distributed or
distributable pursuant to the terms of this Agreement or otherwise, but
determined

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without regard to any additional payments required under this Section V-B) (a
"Payment") would be subject to the excise tax imposed by Section 4999 of the
Internal Revenue Code or any interest or penalties are incurred by the
Executive with respect to such excise tax (such excise tax, together with any
such interest and penalties, are hereinafter collectively referred to as the
"Excise Tax"), then the Executive shall be entitled to receive an additional
payment (a "Gross-Up Payment") in an amount such that after payment by the
Executive of all taxes (including any interest or penalties imposed with
respect to such taxes), including, without limitation, any income taxes (and
any interest and penalties imposed with respect thereto) and Excise Tax
imposed upon the Gross-Up Payment, the Executive retains an amount of the
Gross-Up Payment equal to the Excise Tax imposed upon the Payments.
Notwithstanding the foregoing provisions of this Section V-B-1, if it shall
be determined that the Executive is entitled to a Gross-Up Payment, but that
the Payments do not exceed 110% of the greatest amount (the "Reduced Amount")
that could be paid to the Executive such that the receipt of Payments would
not give rise to any Excise Tax, then no Gross-Up Payment shall be made to
the Executive and the Payments, in the aggregate, shall be reduced to the
Reduced Amount.

                  2.       Subject to the provisions of Section V-B-3, all
determinations required to be made under this Section V-B, including whether
and when a Gross-Up Payment is required and the amount of such Gross-Up
Payment and the assumptions to be utilized in arriving at such determination,
shall be made by PricewaterhouseCoopers LLP or such other certified public
accounting firm as may be designated by the Executive (the "Accounting Firm")
which shall provide detailed supporting calculations both to the Company and
the Executive within 15 business days of the receipt of notice from the
Executive that there has been a Payment, or such earlier time as is requested
by the Company. In the event that the Accounting Firm is serving as
accountant or auditor for the individual, entity or group effecting the
Change of Control, the Executive shall appoint another nationally recognized
accounting firm to make the determinations required hereunder (which
accounting firm shall then be referred to as the Accounting Firm hereunder).
All fees and expenses of the Accounting Firm shall be borne solely by the
Company. Any Gross-Up Payment, as determined pursuant to this Section V-B,
shall be paid by the Company to the Executive within five days of the receipt
of the Accounting Firm's determination. Any determination by the Accounting
Firm shall be binding upon the Company and the Executive. As a result of the
uncertainty in the application of Section 4999 of the Code at the time of the
initial determination by the Accounting Firm hereunder, it is possible that
Gross-Up Payments that will not have been made by the Company should have
been made ("Underpayment"), consistent with the calculations required to be
made hereunder. In the event that the Company exhausts its remedies pursuant
to Section V-B-3 and the Executive thereafter is required to make a payment
of any Excise Tax, the Accounting Firm shall determine the amount of the
Underpayment that has occurred and any such Underpayment shall be promptly
paid by the Company to or for the benefit of the Executive.

                  3.       The Executive shall notify the Company in writing
of any claim by the Internal Revenue Service that, if successful, would
require the payment by the Company of the Gross-Up Payment. Such notification
shall be given as soon as practicable but no later than ten business days
after the Executive is informed in writing of such claim and shall apprise
the Company of the nature of such claim and the date on which such claim is
requested to be paid. The Executive shall not pay such claim prior to the
expiration of the 30-day period following the date on which it gives such
notice to the Company (or such shorter period ending on the date that

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any payment of taxes with respect to such claim is due). If the Company
notifies the Executive in writing prior to the expiration of such period that
it desires to contest such claim, the Executive shall:

                  (a)      give the Company any information reasonably
requested by the Company relating to such claim,

                  (b)      take such action in connection with contesting
such claim as the Company shall reasonably request in writing from time to
time, including, without limitation, accepting legal representation with
respect to such claim by an attorney reasonably selected by the Company,

                  (c)      cooperate with the Company in good faith in order
effectively to contest such claim, and

                  (d)      permit the Company to participate in any
proceedings relating to such claim;

                  provided, however, that the Company shall bear and pay
directly all costs and expenses (including additional interest and penalties)
incurred in connection with such contest and shall indemnify and hold the
Executive harmless, on an after-tax basis, for any Excise Tax or income tax
(including interest and penalties with respect thereto) imposed as a result
of such representation and payment of costs and expenses. Without limitation
on the foregoing provisions of this Section V-B-3, the Company shall control
all proceedings taken in connection with such contest and, at its sole
option, may pursue or forgo any and all administrative appeals, proceedings,
hearings and conferences with the taxing authority in respect of such claim
and may, at its sole option, either direct the Executive to pay the tax
claimed and sue for a refund or contest the claim in any permissible manner,
and the Executive agrees to prosecute such contest to a determination before
any administrative tribunal, in a court of initial jurisdiction and in one or
more appellate courts, as the Company shall determine; provided, however,
that if the Company directs the Executive to pay such claim and sue for a
refund, the Company shall advance the amount of such payment to the
Executive, on an interest-free basis and shall indemnify and hold the
Executive harmless, on an after-tax basis, from any Excise Tax or income tax
(including interest or penalties with respect thereto) imposed with respect
to such advance or with respect to any imputed income with respect to such
advance; and further provided that any extension of the statute of
limitations relating to payment of taxes for the taxable year of the
Executive with respect to which such contested amount is claimed to be due is
limited solely to such contested amount. Furthermore, the Company's control
of the contest shall be limited to issues with respect to which a Gross-Up
Payment would be payable hereunder and the Executive shall be entitled to
settle or contest, as the case may be, any other issue raised by the Internal
Revenue Service or any other taxing authority.

                  4.       If, after the receipt by the Executive of an
amount advanced by the Company pursuant to Section V-B-3, the Executive
becomes entitled to receive any refund with respect to such claim, the
Executive shall (subject to the Company's complying with the requirements of
Section V-B-3) promptly pay to the Company the amount of such refund
(together with any interest paid or credited thereon after taxes applicable
thereto). If, after the

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receipt by the Executive of an amount advanced by the Company pursuant to
Section V-B-3, a determination is made that the Executive shall not be
entitled to any refund with respect to such claim and the Company does not
notify the Executive in writing of its intent to contest such denial of
refund prior to the expiration of 30 days after such determination, then such
advance shall be forgiven and shall not be required to be repaid and the
amount of such advance shall offset, to the extent thereof, the amount of
Gross-Up Payment required to be paid.

                  C.       DEFINITIONS.  For purposes of this Section V:

                  1.       A "Change in Control" of the Company means any of
the following:

                  (a)      Approval by the stockholders of the Company of the
dissolution or liquidation of the Company;

                  (b)      Approval by the stockholders of the Company of an
agreement to merge or consolidate, or otherwise reorganize, with or into one
or more entities that are not subsidiaries or other affiliates, as a result
of which less than 50% of the outstanding voting securities of the surviving
or resulting entity immediately after the reorganization are, or will be,
owned, directly or indirectly, by stockholders of the Company immediately
before such reorganization (assuming for purposes of such determination that
there is no change in the record ownership of the Company's securities from
the record date for such approval until such reorganization and that such
record owners hold no securities of the other parties to such reorganization,
but including in such determination any securities of the other parties to
such reorganization held by affiliates of the Company);

                  (c)      Approval by the stockholders of the Company of the
sale of substantially all of the Company's business and/or assets to a person
or entity which is not a subsidiary or other affiliate; or

                  (d)      Any "person" (as such term is used in Sections
13(d) and 14(d) of the Securities Exchange Act of 1934 (the "Exchange Act")
but excluding any person described in and satisfying the conditions of Rule
13d-1(b)(1) thereunder), becomes the "beneficial owner" (as defined in Rule
13d-3 under the Exchange Act), directly or indirectly, of securities of the
Company representing more than 40% of the combined voting power of the
Company's then outstanding securities entitled to then vote generally in the
election of directors of the Company; or

                  (e)      During any period not longer than two consecutive
years, individuals who at the beginning of such period constituted the Board
of Directors of the Company cease to constitute at least a majority thereof,
unless the election, or the nomination for election by the Corporation's
stockholders, of each new Board member was approved by a vote of at least
three-fourths of the Board members then still in office who were Board
members at the beginning of such period (including for these purposes, new
members whose election or nomination was so approved).

                  2.       "Good Reason" shall mean, without obtaining the
Executive's prior written consent thereto, (a) an adverse and significant
change in the Executive's position, duties, responsibilities, or status with
the Company, (b) a change in the Executive's office location to a

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point more than 35 miles from the Executive's office immediately prior to a
Change in Control; (c) the taking of any action by the Company to eliminate
benefit plans without providing substitutes which, in overall, provide a
substantially similar aggregate value of benefits, to reduce benefits
thereunder or to substantially diminish the aggregate value of incentive
awards or other fringe benefits, (d) any reduction in the Executive's base
salary, (e) any purported termination by the Company of the Executive's
employment other than as expressly permitted by this Agreement, or (f) any
breach of this Agreement by the Company. "Good Reason" shall also mean and
include, without limitation, any termination by the Executive of his
employment with the Company at any time within one year following a Change in
Control, whether with or without reason.

VI.      CONFIDENTIAL INFORMATION.

                  A.       The Executive shall hold in a fiduciary capacity
for the benefit of the Company all secret or confidential information,
knowledge or data relating to the Company or any of its affiliated companies,
and their respective businesses, which shall have been obtained by the
Executive during his employment by the Company and which shall not be or
become public knowledge (other than by acts by the Executive or his
representatives in violation of this Agreement). After termination of the
Executive's employment with the Company, he shall not, without the prior
written consent of the Company, or as may otherwise be required by law or
legal process, communicate or divulge any such information, knowledge or data
to anyone other than the Company and those designated by it; PROVIDED,
however, that the Executive will not be so bound if following a Change in
Control the Executive is terminated without Cause or if the Executive
terminates his employment for Good Reason.

                  B.       The Executive agrees that all lists, materials,
books, files, reports, correspondence, records, and other documents ("Company
material") used, prepared, or made available to the Executive, shall be and
shall remain the property of the Company. Upon the termination of employment
or the expiration of this Agreement, all Company materials shall be returned
immediately to the Company, and the Executive shall not make or retain any
copies thereof.

VII.     SUCCESSORS.

                  A.       This Agreement is personal to the Executive and
shall not, without the prior written consent of the Company, be assignable by
the Executive otherwise than by will or the laws of descent and distribution.
This Agreement shall inure to the benefit of and be enforceable by the
Executive's legal representatives.

                  B.       This Agreement shall inure to the benefit of and
be binding upon the Company and its successors and assigns and any such
successor or assignee shall be deemed substituted for the Company under the
terms of this Agreement for all purposes. As used herein, "successor" and
"assignee" shall include any person, firm, corporation or other business
entity which at any time, whether by purchase, merger or otherwise, directly
or indirectly acquires the stock of the Company or to which the Company
assigns this Agreement by operation of law or otherwise.

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VIII.    WAIVER.

                  No waiver of any breach of any term or provision of this
Agreement shall be construed to be, nor shall be, a waiver of any other
breach of this Agreement. No waiver shall be binding unless in writing and
signed by the party waiving the breach.

IX.      MODIFICATION.

                  This Agreement may not be amended or modified other than by
a written agreement executed by the Executive and the Company.

X.       SAVINGS CLAUSES.

                  A.       If any provision of this Agreement or the
application thereof is held invalid, the invalidity shall not affect other
provisions or applications of the Agreement which can be given effect without
the invalid provisions or applications and to this end the provisions of this
Agreement are declared to be severable.

                  B.       If any provision of this Agreement would, in the
written opinion of the Company's independent accountants, prevent or
substantially interfere with the Company's ability to receive pooling
treatment in any business combination, the offending provision will be deemed
severed from this Agreement and the other provisions of this Agreement shall
not be affected.

XI.      COMPLETE AGREEMENT.

                  This instrument constitutes and contains the entire
agreement and understanding concerning Executive's employment and other
subject matters addressed herein between the parties, and supersedes and
replaces all prior negotiations and all agreements proposed or otherwise,
whether written or oral, concerning the subject matter hereof. This is an
integrated agreement.

XII.     GOVERNING LAW.

                  This Agreement shall be deemed to have been executed and
delivered within the State of California, and the rights and obligations of
the parties hereunder shall be construed and enforced in accordance with, and
governed by, by the laws of the State of California without regard to
principles of conflict of laws.

XIII.    CONSTRUCTION.

                  The captions of this Agreement are not part of the
provisions hereof and shall have no force or effect.

XIV.     COMMUNICATIONS.

                  All notices, requests, demands and other communications
hereunder shall be in writing and shall be deemed to have been duly given if
delivered in person, by telecopy, telex or

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equivalent form of written telecommunication or if sent by registered or
certified mail, return receipt requested, postage prepaid, as follows:

      To Company:               Versicor Inc.
                                34790 Ardentech Ct.
                                Fremont, California  94555
                                Attention:  Corporate Secretary

      With copy to:             O'Melveny & Myers LLP
                                Embarcadero Center West
                                275 Battery Street, 26th Floor
                                San Francisco, California  94111
                                Attention:  Peter T. Healy

      To Executive:             Dinesh V. Patel, Ph.D.
                                45109 Cougar Circle
                                Fremont, California  94539

                  Either party may change the address at which notice shall
be given by written notice given in the above manner. All notices required or
permitted hereunder shall be deemed duly given and received on the date of
delivery, if delivered in person or by telex, telecopy or other written
telecommunication on a regular business day and within normal business hours
or on the fifth day next succeeding the date of mailing, if sent by certified
or registered mail.

XV.      EXECUTION.

                  This Agreement is being executed in one or more
counterparts, each of which shall be deemed an original, but all of which
together shall constitute one and the same instrument. Photographic copies of
such signed counterparts may be used in lieu of the originals for any purpose.

XVI.     LEGAL COUNSEL.

                  The Executive and the Company recognize that this is a
legally binding contract and acknowledge and agree that they have had the
opportunity to consult with legal counsel of their choice.

XVII.    SURVIVAL.

                  The provisions of this Agreement shall survive the term of
this Agreement to the extent necessary to accommodate full performance of all
such terms.

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

VERSICOR INC.:                           EXECUTIVE:

By:  /s/ George F. Horner III            By:  /s/ Dinesh V. Patel, Ph.D.
    -------------------------------          -------------------------------

Name:  George F. Horner III              Name:  Dinesh V. Patel, Ph.D.

Title:  President and CEO








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