Document:

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                                                                  EXHIBIT 10.141

                              SEVERANCE AGREEMENT

     THIS AGREEMENT, made this 17th day of December, 1999, by and between
Pharmaceutical Product Development, Inc. ("PPD") and Francis J. Casieri
("Employee").

     WHEREAS, Employee is a valued employee of PPD and in order to induce
Employee to remain in the employ of PPD, PPD desires to provide the severance
benefits hereinafter described in the event of a "Change in Control", as
hereinafter defined, of PPD.

     NOW, THEREFORE, it is agreed as follows:

     1.   Definitions
          -----------

          a.  "Change in Control" means a change of 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 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 becomes the beneficial owner, directly or indirectly, of
securities of PPD representing 50% or more of the combined voting power of PPD's
then outstanding securities.

          b.  "Constructive Termination" means a termination of Employee's
employment by PPD during the Covered Period initiated by Employee after (i) a
substantial diminution or alteration in the duties of Employee, (ii) a reduction
by PPD in Employee's base salary in effect on the date of the Change in Control,
or (iii) the relocation of Employee's primary work location to a location that
is more than twenty-five (25) miles from Employee's primary work location prior
to the Change in Control. Constructive Termination specifically does not include
termination of Employee by reason of death, Disability or retirement at or after
age 65. Employee shall give PPD written notice of a Constructive Termination,
which notice shall provide a brief description of the circumstances which
Employee asserts gives rise to a right of Constructive Termination, and PPD
shall have ten (10) days from receipt of said notice within which to remedy said
circumstances.

          c.  "Covered Period" means the time period commencing on the date of
and coincident with a Change of Control and ending one year thereafter.

          d.  "Disability" means the inability of Employee to perform his
assigned duties for PPD for a period of three (3) months due to Employee's
physical or mental illness as determined by a reputable medical doctor.

          e.  "PPD" means Pharmaceutical Product Development, Inc. and all of
its subsidiaries and affiliated entities.
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          f.  "Termination for Cause" means (i) an act or acts involving fraud,
embezzlement or theft from PPD, (ii) Employee's willful and repeated failure to
follow directions of the Board of Directors that continues for at least ten (10)
days following written notice of the Board of Directors of such failure to
follow directions, or (iii) termination for cause as defined in and made
pursuant to a then effective employment agreement, if any, between Employee and
PPD.

     2.   Compensation  Upon Change of Control.     If during the Covered Period
          -------------------------------------
(i) PPD terminates Employee's employment for reason other than Termination for
Cause or (ii)  Employee's employment is terminated by reason of Constructive
Termination, Employee shall be entitled to the following compensation and
benefits:

          a.  PPD shall pay Employee a lump sum equal to Employee's W-2
compensation for the twelve (12) months ending on the last day of the month
preceding the month of Employee's termination, said sum to be paid within ten
(10) days after Employee's termination of employment.

          b.  PPD shall pay Employee any bonus or deferred compensation (whether
in the form of cash, stock or otherwise) accrued but unpaid as of Employee's
termination, said sum to be paid within ten (10) days after Employee's
termination of employment.

          c.  For a period of one-year after Employee's termination of
employment with PPD, PPD shall continue to pay for and provide existing employee
welfare benefits which Employee is receiving as of the date of termination of
employment, including life insurance, health, medical, dental, vision and
wellness, accidental death and dismemberment and disability benefits; provided,
however, that PPD's obligations under this clause shall terminate from the date
that Employee first becomes eligible after termination of employment with PPD
for similar coverage under another employer's plan.

          d.  Notwithstanding anything to the contrary in any award agreement
for non-qualified stock options, (i) all unvested shares underlying PPD non-
qualified stock options granted more than six months prior to the date of
Employee's termination shall become fully vested as of the date of Employee's
termination, and (ii) Employee shall continue to be treated under each award
agreement as if he was an employee of PPD until the first to occur of (x) the
third anniversary of Employee's termination of employment, or (y) the expiration
of the exercise period provided for therein; provided, however, in the event of
Employee's death or his disability (as disability is defined in the award
agreement) after the date of Employee's termination of employment hereunder, the
time for exercise after death or such disability prescribed in the award
agreement shall apply. The provisions of this subsection shall also apply to any
and all substitute stock options granted to Employee in exchange for Employee's
PPD non-qualified stock options to which this subsection applies.

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     3.   Miscellaneous.
          -------------

          a.  PPD 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 PPD, to expressly assume and agree to perform this
Agreement in the same manner and to the same extent that PPD would be required
to perform it if no succession had taken place.

          b.  This Agreement shall inure to the benefit of and be enforceable by
Employee's personal or legal representatives, executives, administrators,
successors, heirs, distributees, devisees and legatees.

          c.  For purposes of this Agreement, notices and all other
communications provided for in the Agreement shall be in writing and shall be
given (i) by certified mail, return receipt requested, postage prepaid, or (ii)
by recognized overnight carrier, and shall be deemed received when actually
received. Notices shall be addressed as follows:

          If to PPD:      Pharmaceutical Product Development, Inc.
                          3151 17th South Street
                          Wilmington, North Carolina  28412
                          Attention: Chief Executive Officer

          If to Employee: Francis J. Casieri

                          _____________________________

                          _____________________________

Either party hereto may change the notice address by giving notice thereof in
the same manner as provided for herein.

          d.  No waiver by either party hereto at any time of any breach by the
other party hereto of, or compliance with, any provision or condition of this
Agreement to be performed by such other party shall be deemed a subsequent
waiver of the same or similar provisions or conditions.

          e.  No agreements or representations, oral or otherwise, expressed or
implied, with respect to the subject matter hereof have been made by either
party which are not set forth expressly in this agreement, and this Agreement
supersedes and replaces in its entirety all prior agreements and
representations, expressed, implied,  oral or otherwise, made by PPD to or with
Employee.

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          f.  This Agreement shall be governed by and interpreted under the laws
of the State of North Carolina.

          g.  The invalidity or unenforceability of any provision of this
Agreement shall not affect the validity or enforceability of any other provision
of this Agreement.

          h.  This Agreement may be 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.

          i.   All legal expenses incurred by Employee in the successful
enforcement of any of the terms of this Agreement shall be paid by PPD.

     IN WITNESS WHEREOF, the parties have executed this Agreement effective the
date first hereinabove set forth.

                                        PHARMACEUTICAL PRODUCT
                                        DEVELOPMENT, INC.

                                        By: /s/ Fred N. Eshelman
                                            --------------------
                                        Name:  Fred N. Eshelman
                                        Title: Chief Executive Officer

                                        EMPLOYEE

                                             /s/ Francis J. Casieri     (SEAL)
                                        --------------------------------
                                        Name:  Francis J. Casieri

                                       4<PAGE>

                                                                  EXHIBIT 10.142

                      TERMINATION OF EMPLOYMENT AGREEMENT

     THIS  TERMINATION OF EMPLOYMENT AGREEMENT, made this 8th day of February,
2000, by and between Pharmaceutical Product Development, Inc. ("PPD"), and Rudy
C. Howard ("Employee").

     WHEREAS, PPD and Employee entered into that certain employment agreement
dated January 1, 1998 (the "Employment Agreement"); and

     WHEREAS, the parties desire to terminate the Employment Agreement pursuant
to the terms and conditions more specifically set forth herein.

     NOW, THEREFORE, in consideration of the mutual promises, covenants and
considerations contained herein, and other good and valuable consideration, the
receipt and sufficiency of which are hereby acknowledged, the parties agree as
follows:

     1.  Termination of Employment Agreement. The Employment Agreement shall be
         ------------------------------------
deemed terminated as of the close of business on February 8, 2000 (the
"Termination Date").

     2.  Rights and Obligations.  Neither party hereto shall have any further
         ----------------------
rights or obligations under the Employment Agreement, except (a) such rights and
obligations as shall have accrued prior to the Termination Date, and (b) such
rights and obligations which by the terms of the Employment Agreement survive
the Termination date.

     3.  Miscellaneous.
         -------------

          a.  This agreement constitutes the entire agreement between the
parties with respect to the subject matter hereof and may not be altered or
amended except by writing signed by the parties.

          b.  This agreement shall be governed by the laws of State of North
Carolina.

          c.  This agreement shall inure to the benefit of and be binding upon
PPD, its successors and assigns, and Employee, his heirs, successors, assigns
and personal representatives.
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     IN WITNESS WHEREOF, the parties have caused this agreement to be executed
as of the date first hereinabove set forth.

PHARMACEUTICAL PRODUCT DEVELOPMENT, INC.

By:  /s/ Fredric N. Eshelman
     -----------------------
Name:  Fredric N. Eshelman
Title: Chief Executive Officer

  /s/ Rudy C. Howard   (SEAL)
-----------------------
Rudy C. Howard

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