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                                                                   EXHIBIT 10.63
 
                               September 6, 1996
 
Mr. John H. Timoney
Senior Vice President
Applied Bioscience International Inc.
117 Leabrook Lane
Princeton, New Jersey 08540
 
Dear John:
 
     APPLIED BIOSCIENCE INTERNATIONAL INC. ("APBI" or the "Company") considers
the continuing maintenance of a sound and vital management to be essential to
protecting and enhancing the best interests of the Company and its shareholders.
In this connection, the Company recognizes that, as is the case with many
publicly held corporations, the uncertainty and questions which a potential
change of control may raise among management may result in the departure or
distraction of management personnel to the detriment of the Company and its
shareholders. The Company further recognizes that in your role as a Senior Vice
President of the Company and an officer of APBI Investor Relations, Inc., you
will have increased duties and responsibilities in responding to a change of
control. Accordingly, the Company's Board of Directors has determined that given
the pending merger agreement between the Company and a wholly-owned subsidiary
of Pharmaceutical Product Development, Inc., it is imperative that the Company
and the Board of Directors be able to rely upon you to remain in your position
and to provide advice, if requested, as to the best interests of the Company.
 
     In order to induce you to remain in the employ of the Company and to
provide the Company with additional flexibility regarding your employment, this
letter agreement sets forth the terms of your continued employment and the
severance benefits which the Company agrees will be provided to you in the event
of your termination of full-time employment following a "change in control of
the Company" (as defined in Section 2 hereof) or under the circumstances
described below.
 
     1.  NON-RENEWAL OF EXISTING EMPLOYMENT AGREEMENT; TERMS OF CONTINUED
EMPLOYMENT.  (a) You acknowledge and agree that your existing employment
agreement will not be renewed by the Company on September 6, 1996. Thereafter,
you will continue to be employed by the Company as a Senior Vice President at an
annual salary of $180,000, but you shall be considered an "at-will" employee of
the Company for purposes of full-time employment with the Company. You will be
subject to the direction of the Chief Executive Officer of the Company and will
perform such duties as may be assigned to you by the Chief Executive Officer of
the Company, consistent with your position as a Senior Vice President of the
Company. Your services will be performed primarily at the offices of the Company
in Princeton, New Jersey, or such other location as you and the Company may
mutually agree. You will not be obligated to relocate your personal residence in
connection with the perform of your duties hereunder. You will be entitled to
the severance payments set forth in Section 3 upon your termination of your
full-time employment, subject to the provisions of Section 3.
 
     (b) Upon termination of your full-time employment with the Company, you
will be employed by the Company as a part-time employee pursuant to the terms of
the April 30, 1993 extension letter between you and the Company (the "Extension
Letter"), a copy of which is attached hereto as Exhibit A. The "Extension
Period" as defined in Section 2 of the Extension Letter shall commence as of the
last day of your full-time employment with the Company.
 
     2. CHANGE IN CONTROL.  For purposes of this Agreement, a "change in control
of the Company" shall mean a change in control of a nature that would be
required to be reported in response to Item 6(e) of Schedule 14A of Regulation
14A promulgated under the Securities Exchange Act of 1934, as amended ("Exchange
Act"); provided that, without limitation, such a change in control shall be
deemed to have occurred if any "person" (as such term is used in Sections 13(d)
and 14(d)(2) of the Exchange Act) is or
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becomes the beneficial owner, directly or indirectly, of securities of the
Company representing fifty percent (50%) or more of the combined voting power of
the Company's then outstanding securities.
 
     3. COMPENSATION UPON TERMINATION OF FULL-TIME EMPLOYMENT.  Upon your
involuntary termination of full-time employment by the Company (other than for
"cause" as defined herein) within three (3) months prior to a change in control,
or upon your voluntary or involuntary termination of full-time employment (other
than for "cause" as defined herein) within six (6) months following a change in
control, the Company shall make a lump sum payment to you equal to six (6)
months base salary, based upon the salary rate in effect for you as of the date
of your termination of full-time employment. This lump sum payment shall be made
no later than ten (10) days following the termination of your full-time
employment with the Company. In addition, you shall be entitled to receive
employer-provided health and dental benefits for six (6) months following your
termination of full-time employment. The six (6) months of employer-provided
benefits shall be counted against your eighteen (18) months of COBRA coverage.
The lump sum payment and benefits provided under this Agreement shall be in lieu
of any severance payment to which you may be entitled under an "employee benefit
plan" maintained by the Company or a subsidiary For purposes of this agreement,
"cause" shall mean an act or acts involving fraud, embezzlement or theft from
the Company, or your willful and repeated failure to follow the lawful
directions of the Board of Directors consistent with your position with the
Company that continues for at least ten (10) days following written notice from
the Board of Directors of such failure to follow such directions.
 
     4. LAPSE.  Should you voluntarily leave employment prior to a change in
control or if you are terminated for cause either prior to or after to a change
in control, this Agreement shall lapse and be of no other force and effect and
no compensation will be payable to you hereunder.
 
     5. SUCCESSORS; BINDING AGREEMENT.  (a) The Company will require any
successor (whether direct or indirect, by purchase, merger, consolidation or
otherwise) to all or substantially all of the business and/or assets of the
Company, to expressly assume and agree to perform this Agreement in the same
manner and to the same extent that the Company would be required to perform it
if no such succession had taken place.
 
     (b) This Agreement shall inure to the benefit of and be enforceable by your
personal or legal representatives, executors, administrators, successors, heirs,
distributees, devisees and legatees.
 
     6. NOTICE.  For the purposes of this Agreement, notices and all other
communications provided for in the Agreement shall be in writing and shall be
deemed to have been duly given when delivered or mailed by registered mail,
return receipt requested, postage prepaid, addressed to the respective addresses
set forth on the first page of this Agreement, provided that all notices to the
Company shall be directed to the attention of the Chief Executive Officer of the
Company with a copy of the Secretary of the Company, or to such other address as
either party may have furnished to the other in writing in accordance herewith,
except that notices of change of address shall be effective only upon receipt.
 
     7. MISCELLANEOUS.  No provisions of this Agreement may be modified, waived
or discharged unless such waiver, modification or discharge is agreed to in
writing signed by you and such officer as may be specifically designated by the
Board of Directors of the Company. No waiver by either party hereto at any time
of any breach by the party hereto of, or compliance with, any condition or
provision of this Agreement to be performed by such other party shall be deemed
a waiver of similar or dissimilar provisions or conditions at the same or at any
prior or subsequent time. No agreement or representations, oral or otherwise,
express or implied, with respect to the subject matter hereof have been made by
either party which are not set forth expressly in this Agreement. This Agreement
supersedes and replaces in its entirety that certain letter agreement between
the Company and you dated September 1, 1995. The validity, interpretation,
construction and performance of this Agreement shall be governed by the laws of
the State of Delaware.
 
     8. VALIDITY.  The invalidity or unenforceability of any provisions of this
Agreement shall not effect the validity or enforceability of any other provision
of this Agreement, which shall remain in full force and effect.
 
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     9. COUNTERPARTS.  This Agreement may be executed in one or more
counterparts, each of which shall be deemed to be an original but all of which
together will constitute one and the same instrument.
 
     If this letter correctly sets forth our agreement on the subject matter
hereof, kindly sign and return to the Company the enclosed copy of this letter
which will then constitute our agreement on this subject.
 
                                        Sincerely,
 
                                        APPLIED BIOSCIENCE INTERNATIONAL INC.
 
                                        By: /s/ KENNETH H. HARPER
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                                           Kenneth H. Harper
                                           Chief Executive Officer
 
AGREED TO THIS 6TH DAY OF
SEPTEMBER, 1996
 
By: /s/ JOHN H. TIMONEY
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    John H. Timoney

 
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