Document:

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                                                                  EXHIBIT 10.139

                       THIRD AMENDMENT TO LOAN AGREEMENT

          THIS THIRD AMENDMENT TO LOAN AGREEMENT (this "Amendment") is made as
of the 11th day of November, 1999, by and among PHARMACEUTICAL PRODUCT
DEVELOPMENT, INC., a North Carolina corporation (together with its successors,
the "Borrower"); PPD DEVELOPMENT, INC., (the "Guarantor"); and WACHOVIA BANK,
N.A., a national banking association (together with its endorsees, successors
and assigns, the "Bank").

                               R E C I T A L S:
                               ---------------

          The Borrower, the Guarantor and the Bank are parties to a certain Loan
Agreement dated as of August 7, 1997, as amended pursuant to an Amendment to
Loan Agreement dated as of August 6, 1998 and a Second Amendment to Loan
Agreement dated as of January 30, 1999 (the "Loan Agreement").

          Capitalized terms used in this Amendment which are not otherwise
defined in this Amendment shall have the respective meanings assigned to them in
the Loan Agreement.

          The Borrower has requested certain modifications to the Loan Agreement
and the Bank is willing to modify the Loan Agreement subject to the terms,
provisions and conditions set forth in this Amendment.

          NOW, THEREFORE, in consideration of the Recitals, the mutual promises
herein contained and other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the Borrower, the Guarantor and
the Bank, intending to be legally bound hereby, agree as follows:

          SECTION 1.  Recitals.  The Recitals are incorporated herein by
                      --------
reference and shall be deemed to be a part of this Amendment.

          SECTION 2.  Amendments.  Effective from and after August 5, 1999, the
                      ----------
Loan Agreement is hereby amended as follows:

          2.1  Extension of Termination Date. The Termination Date is hereby
               -----------------------------
extended to August 3, 2000.

          2.2  Section 2.3 is hereby amended and restated to read in its
entirety as follows:

          2.3  Interest Rate. Loans outstanding hereunder shall bear interest at
               -------------
a per annum rate equal to (i) the LIBOR Rate plus the Applicable Margin or (ii)
                                             ----
the Base Rate plus the
              ----
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Applicable Margin, as the Borrower may elect; provided that after the occurrence
and during the continuance of an Event of Default, the principal and, to the
extent permitted by law, interest on the Loans and any other amounts owing
hereunder shall bear interest, payable on demand, at a rate equal to the Base
Rate plus three percent (3%). Interest will be payable in arrears on each
Interest Payment Date. As used herein, the term "Applicable Margin" shall mean,
for any day, an amount equal to: (1) five eighths of one percent (0.625%) on
each day that the aggregate principal amount of all Loans outstanding on such
day shall be less than the amount equal to fifty percent (50%) of the Commitment
on such day; and (2) eight hundred twenty-five thousandths of one percent
(.825%) on each day that the aggregate principal amount of all Loans outstanding
on such day is equal to or greater than the amount equal to fifty percent (50%)
of the Commitment on such day. For purposes of determining the Applicable Margin
for any day, a change in the principal amount of all outstanding Loans shall be
effective on the date of such change.

          2.4 In Section 6.9 subsections (f) and (g) are re-lettered as (g) and
(h), respectively, and a new subsection (f) is hereby added to Section 6.9 of
the Loan Agreement to read as follows:

          (f) Investments in and to ADoctorInYourHouse.com in an aggregate
     principal amount (on a cost basis) not to exceed $5,000,000 at any time;

          SECTION 3.  Conditions to Effectiveness.  The effectiveness of this
                      ---------------------------
Amendment and the obligations of the Bank hereunder are subject to receipt by
the Bank of the following:

          (a) an original Amendment, duly executed by the Borrower and the
     Guarantor;

          (b) a certificate of incumbency satisfactory to the Bank, certifying
     as to the names, true signatures and incumbency of the officer or officers
     of the Borrower and the Guarantor authorized to execute and deliver this
     Amendment;

          (c) such other documents or items as the Bank or its counsel may
     reasonably request.

The effectiveness of this Amendment and the obligations of the Bank hereunder
are further subject to the condition that no Event of Default or event or
condition which with notice or lapse of time, or both, would constitute an Event
of Default under the Loan Agreement, as hereby amended, shall have occurred and
be continuing, and the representations and warranties contained in Section 5 of
the Loan Agreement, as amended herein, are true on and as of the date hereof.

          SECTION 4.  No Other Amendment.  Except for the amendments set forth
                      ------------------
above, the Loan Agreement shall remain unchanged and in full force and effect.
This Amendment is not intended to effect, nor shall it be construed as, a
novation.  The Loan Agreement and this Amendment shall be construed together as
a single agreement.  Nothing

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herein contained shall waive, annul, alter, limit, diminish, vary or affect any
provision, condition, covenant or agreement contained in the Loan Agreement,
except as herein amended, nor affect or impair any rights, powers or remedies
under the Loan Agreement as hereby amended. The Bank does hereby reserve all of
its rights and remedies against all parties who may be or may hereafter become
secondarily liable for the repayment of the Loan. The Borrower and the Guarantor
promise and agree to perform all of the requirements, conditions, agreements and
obligations under the terms of the Loan Agreement, as hereby amended, the Loan
Agreement, as amended, being hereby ratified and affirmed. The Borrower and
Guarantor hereby expressly agree that the Loan Agreement, as amended, is in full
force and effect and confirm that they have no set off, counterclaim or defense
with respect to the Loan Agreement, the Loan, the Note, the Guaranty contained
in the Loan Agreement or the Guaranteed Obligations.

          SECTION 5.  Representations and Warranties.  The Borrower and the
                      ------------------------------
Guarantor hereby represent and warrant to the Bank as follows:

          (a) No Event of Default or event or condition which with notice or
     lapse or time, or both, would constitute an Event of Default under the Loan
     Agreement, as hereby amended, has occurred and is continuing on the date
     hereof.

          (b) The representations and warranties contained in Section 5 of the
     Loan Agreement, as amended herein, are true on and as of the date of this
     Amendment.

          (c) This Amendment has been duly authorized, validly executed and
     delivered by one or more authorized officers of the Borrower and the
     Guarantor, and constitutes the legal, valid and binding obligation of the
     Borrower and Guarantor enforceable against them in accordance with its
     terms.

          (d) The execution and delivery of this Amendment and the Borrower's
     and the Guarantor's performance hereunder do not and will not require the
     consent or approval of any regulatory authority or governmental authority
     or agency having jurisdiction over the Borrower or the Guarantor, nor be in
     contravention of or in conflict with the Articles of Incorporation or
     Bylaws of the Borrower or the Guarantor, or the provision of any statute,
     or any judgment, order or indenture, instrument, agreement or undertaking
     to which the Borrower or the Guarantor is party or by which the Borrower's
     or the Guarantor's assets or properties are or may become bound.

          SECTION 6.  Counterparts.  This Amendment may be executed in
                      ------------
counterparts, each of which shall be deemed to be an original and all of which,
taken together, shall constitute one and the same agreement.

          SECTION 7.  Governing Law.  This Amendment shall be deemed to be made
                      -------------
pursuant to the laws of the State of North Carolina with respect to agreements
made and to be

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performed wholly in the State of North Carolina and shall be construed,
interpreted, performed and enforced in accordance therewith.

          SECTION 8.  Costs and Expenses.  The Borrower shall pay any and all
                      ------------------
out-of-pocket expenses in connection with the preparation, execution and
delivery of this Amendment, including, without limitation, the fees and expenses
of the Bank's counsel in connection therewith.

          SECTION 9.  Entire Agreement.  This Amendment contains the entire
                      ----------------
agreement of the parties with respect to the subject matter hereof, and there
are no representations, inducements or other provisions among the parties
regarding such subject matter other than those expressed herein in writing.  All
changes, additions or deletions to this Amendment must be in writing and signed
by all parties.

          IN WITNESS WHEREOF, the parties hereto have caused their respective
duly authorized officers or representatives to execute and deliver this
Amendment as of the day and year first above written.

                                             BORROWER:

ATTEST:                                      PHARMACEUTICAL PRODUCT
                                             DEVELOPMENT, INC.

/s/ Fred B. Davenport, Jr.   Secretary       By: /s/ Rudy C. Howard
--------------------------                   ----------------------
                                             Title: CFO
[CORPORATE SEAL]

                                             BANK:

                                             WACHOVIA BANK, N.A.

                                             By: /s/ Keith Sherman
                                                 ----------------------
                                             Title: SVP
                                                    ---

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                                  GUARANTOR:

ATTEST:                                  PPD DEVELOPMENT, INC.

/s/ Fred B. Davenport, Jr.           By: /s/ Rudy C. Howard
------------------------                 -------------------
      Secretary                      Title:       CFO
      ---------                             ----------------
      [Corporate Seal]

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                                                                  EXHIBIT 10.140

                             EMPLOYMENT AGREEMENT
                             --------------------

          THIS EMPLOYMENT AGREEMENT (hereinafter the "Agreement"), made this
17th day of December, 1999 (the "Effective Date"), by and between PPD
Development Development, Inc., a Texas corporation (hereinafter "PPD Development
Development"), and Francis J. Casieri (hereinafter "Employee").

                                   RECITALS:

          A.  Employee desires employment upon the terms and conditions herein
stated.

          B.  PPD Development desires to employ Employee upon the terms and
conditions herein stated.

          C.  Employee and PPD Development desire to embody in writing the terms
and conditions of such employment in this Agreement.

          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 hereby
agree as follows:

          1.  Employment.  PPD Development hereby employs Employee and Employee
              ----------
hereby accepts such employment on a full time basis as Senior Vice President -
Global Business Development upon the terms and conditions hereinafter set forth.

          2.  Term.   The term of this Agreement shall be for one year,
              ----
beginning January 1, 2000  and ending December 31, 2000, unless sooner
terminated as provided herein.  Thereafter, this Agreement shall be
automatically renewed for successive one-year terms upon the terms and
conditions herein set forth except for (a) salary adjustments as provided for in
Section 9 below and (b) new bonus plans as provided in Section 3 below, unless
either party gives notice as herein provided to the other of said party's intent
not renew this Agreement not less than 60 days prior to the expiration of the
one-year term then in effect.

          3.  Salary.  For all services rendered by Employee under this
              ------
Agreement, PPD Development shall pay to employee an annual base salary of
$162,000 for the initial one-year term hereof.  During the initial one-year term
of this Agreement Employee shall also be entitled to a Quarterly Bonus if the
Businesses (as hereinafter defined) attain a certain level of Authorizations for
the applicable quarter, as set forth in Appendix I attached.  Each Quarterly
                                        ----------
Bonus to which Employee is entitled shall be paid within thirty (30) days after
its determination. Employee shall also be entitled to an annual bonus as
provided for in Appendix I attached, which annual bonus, if any, shall be paid
                ----------
to Employee at the same time annual bonuses, if any, for the initial one-year
term
<PAGE>

hereof are or would have been paid to other senior executives of PPD
Development. In addition, Employee shall be entitled to an award of non-
qualified stock options under the Pharmaceutical Product Development, Inc.
("PPD") Equity Compensation Plan if Authorizations for the Businesses attain
certain Annual Targets for the initial one-year term hereof as set forth in
Appendix I.  Any award of stock options for the initial one-year term shall have
----------
an exercise price equal to the NASDAQ closing price on December 31, 2000, and
shall contain such other terms and conditions, including a three-year linear
vesting schedule, as included in stock option awards generally for other senior
executives of PPD Development.  A new bonus plan shall be agreed upon by
Employee and PPD Development  for each  one-year renewal term of this Agreement.

          4.  Duties.  Employee shall have overall responsibility for business
              ------
development  of (a) PPD Development and all of its subsidiaries as of the
Effective Date, except Pharmaco Investments, Inc., (b) PPD Global Ltd., (c)
Leicester Clinical Research Centre Ltd. and (d) Chelmsford Clinical Trials Unit
Ltd. (collectively, the "Businesses").  Employee's duties shall include but not
be limited to supervision of the Businesses' sales and bids and contracts
divisions.  Employee shall carry out his duties and responsibilities under the
general supervision of the Chief Executive Officer of PPD.  Employee shall
undertake such travel as may be required to perform the duties prescribed
herein.  During the term of this Agreement, Employee shall devote substantially
all of his working time, attention and energies to the business of PPD
Development.

          5.  Working Facilities.  PPD Development shall furnish Employee with
              ------------------
office space, equipment, technical, secretarial and clerical assistance and such
other facilities, services, support and supplies as may be reasonably needed to
perform the duties herein prescribed in an efficient and professional manner.

          6.  Non-Compete.  During the term of this Agreement, Employee hereby
              -----------
agrees that he shall not (a) become an officer, employee, director, agent,
representative, member, associate or consultant of or to a corporation,
partnership or other business entity or person, (b) directly or indirectly
acquire a proprietary interest in a corporation, partnership or other business
entity or person, or (c) directly or indirectly own any stock in a corporation
(other than a publicly traded corporation of which Employee owns less than five
percent (5%) of the outstanding stock) which is engaged in the business of
managing clinical research programs for pharmaceutical and medical products or
in any other business which is developed by PPD Development during the term of
this Agreement anywhere in the United States (whether or not such business is
physically located within the United States).  The parties agree that the
business and operations of PPD Development are national in scope.  For that
reason, the parties agree that a geographical limitation on the foregoing
covenant is not appropriate.

          7.  Termination.  Notwithstanding any other provision of this
              -----------
Agreement, PPD Development may terminate Employee's employment hereunder upon
the occurrence of any of the following events:

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               a.  Death of Employee.

               b.  A determination by the Chief Executive Officer of PPD, acting
in good faith but made in the sole discretion of the Chief Executive Officer,
that Employee has failed to substantially perform his duties under this
Agreement.

               c.  A determination by the Chief Executive Officer of PPD, acting
in good faith but made in the sole discretion of the Chief Executive Officer,
that Employee (i) has become physically or mentally incapacitated and is unable
to perform his duties under this Agreement as a result of such disability, which
inability continues for a period of sixty (60) consecutive calendar days, (ii)
has breached any of the material terms of this Agreement, including failure to
meet Quarterly Targets as set forth in Appendix I attached, (iii) has
                                       ----------
demonstrated gross negligence or willful misconduct in the execution of his
duties, or (iv) has been convicted of a felony.

          8.   Disclosure of Information. As a condition of employment, Employee
               -------------------------
shall abide by all of the terms of that certain Proprietary and Inventions
Agreement between Employee and PPD dated September 7, 1999.

          9.   Benefits.  During the term hereof, Employee shall be entitled to
               --------
participate in all benefits provided by PPD Development to its employees
generally, including but not limited to health insurance, disability insurance
and retirement plans, all of which are currently provided to employees of PPD
Development, subject to the eligibility requirements of any plan(s) establishing
same. Employee shall be subject to PPD Development's policies applicable to
other executive employees of PPD Development with respect to periodic reviews
and increases in salary, and shall be considered for and eligible to participate
in benefits, if any, provided generally by PPD Development to its executive
employees, including but not limited to issuance of stock options, cash bonuses,
etc., to the extent such stock options, bonuses, etc., are not otherwise
provided for herein (including in Appendix I), in connection with Employee's
                                  ----------
duties and performance as an executive employee. Employee shall be entitled to
four (4) weeks paid vacation during each year.

          10.  Expenses.  PPD Development shall pay all expenses of Employee
               --------
which are directly related to Employee's duties hereunder in accordance with
Company guidelines in effect from time to time.

          11.  Remedies.  In the event of Employee's actual or threatened breach
               --------
of the provisions of Section 6 of this Agreement, PPD Development shall be
entitled to a temporary restraining order and/or permanent injunction
restraining Employee from such breach.  Nothing herein shall be construed as
preventing PPD Development from pursuing any other available remedies for such
breach or threatened breach, including recovery of damages from Employee and
from any corporation, partnership or other business entity or person with which
the Employee has entered or attempted to enter into a relationship.

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          12.  Entire Agreement.  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 agreement in writing signed by the parties.

          13.  Waiver of Breach.  Waiver by either party of a breach of any
               ----------------
provision of this Agreement by the other party shall not operate as a waiver of
any subsequent breach by the other party.  No waiver shall be valid unless in
writing and signed by the party against whom the waiver is sought.

          14.  Severability.  If any portion of this Agreement shall be declared
               ------------
invalid by a court of competent jurisdiction, the remaining portion shall
continue in full force and effect as if this Agreement has been executed with
the invalid portion eliminated and this Agreement shall be so construed.

          15.  Benefit.  This Agreement shall inure to the benefit of and be
               -------
binding upon PPD Development, its successors and assigns, and Employee, his
heirs, successors, assigns and personal representatives.

          16.  Applicable Law.  This Agreement shall be governed by the laws of
               --------------
the State of North Carolina.

          17.  Assignment.  Neither party hereto may assign said party's rights
               ----------
or obligations hereunder without the prior written consent of the other.

          18.  Notice.  Any notice required or permitted hereunder shall be
               ------
delivered in person or mailed certified mail, return receipt requested, if to
either party  at PPD's principal office in Wilmington, North Carolina (and, in
addition as to Employee, at his last known residence address) and shall  be
deemed received when actually received.  Any notice from Employee to PPD
Development shall be addressed to the Chief Executive Officer of PPD.  Either
party hereto may change the notice address provided for herein upon ten (10)
days prior written notice to the other in the manner prescribed.

          19.  Arbitration.  Any dispute, controversy or claim arising out of or
               -----------
relating to this Agreement, including but not limited to any breach, or as to
its existence, validity, interpretation, performance or non-performance, or
damages, including claims in tort, shall be decided by a single neutral
arbitrator in Wilmington, North Carolina in binding arbitration pursuant to the
commercial Arbitration Rules of the American Arbitration Association then in
effect.  The parties to any such arbitration shall be limited to the parties to
this Agreement or any successor thereof.   The arbitration shall be conducted in
accordance with the procedural laws of the United States Federal Arbitration
Act, as amended.  The written decision of the arbitrator shall be final and
binding, and may be entered and enforced in any court of competent jurisdiction
and each party specifically acknowledges and agrees to waive any right to a jury
trial in any such

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<PAGE>

forum. Each party to the arbitration shall pay its fees and expenses, unless
otherwise determined by the arbitrator.

          20.  Amendment; Modification.  No amendment or modification of this
               -----------------------
Agreement and no waiver by any party of the breach of any covenant contained
herein shall be binding unless executed in writing by party against whom
enforcement of such amendment, modification or waiver is sought.

          21.  Counterparts.  This Agreement may be executed in multiple
               ------------
counterparts, each of which shall be deemed an original and all of which taken
together  shall constitute one and the same Agreement.

          22.  Descriptive Headings: Interpretation.  The descriptive headings
               ------------------------------------
in this Agreement are inserted for convenience of reference only and are not
intended to be part of or to affect the meaning or interpretation of this
Agreement.

          IN WITNESS WHEREOF, the parties have caused this Agreement to be
executed as of the date first hereinabove set forth.

                              PPD DEVELOPMENT, INC.

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

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

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