<PAGE>
                                                                  Exhibit 10.20



This Agreement made this      day of February 1997, at Montreal, Quebec.


AMONG:                                  CLINTRIALS BIORESEARCH LTD., a
                                        corporation incorporated under the laws
                                        of Quebec ("ClinTrials");


AND:                                    BIO-RESEARCH LABORATORIES LTD., a
                                        corporation incorporated under the laws
                                        of Quebec ("BioResearch");


AND:                                    NORAH K. TAYLOR, chartered accountant,
                                        residing and domiciled in the district
                                        of Montreal, province of Quebec (the
                                        "Custodian").

            WHEREAS Bio-Research established an employee benefit plan (the
"Plan") for certain of its employees by way of an agreement dated December 30,
1983;

            WHEREAS the Custodian is the current custodian of the Plan;

            WHEREAS substantially all of the assets of Bio-Research were
acquired by ClinTrials effective July 24, 1996 and the participants in the Plan
ceased to work for Bio-Research and commenced to work for ClinTrials as at that
date;

NOW THEREFORE THE PARTIES HERETO AGREE AS FOLLOWS:

1.          Bio-Research and ClinTrials hereby acknowledge and agree that Bio
Research has assigned and transferred to ClinTrials, and ClinTrials has accepted
and assumed from Bio-Research, all rights, responsibilities, and obligations of
the employer in regard to the Plan, the whole pursuant to that certain General
Conveyance of Assets made as of July 24, 1996 by and among ClinTrials,
Bio-Research and ClinTrials Research Inc., a copy of which is attached hereto.
For greater certainty, the parties hereto acknowledge that Connaught BioSciences
Inc. (formerly CDC Life Sciences Inc.) is not, and has not been since December
1989, a participating employer in the Plan.

2.          The previous Schedule A to the Plan, listing the participants
therein, is repealed and replaced by the attached Schedule A.

3.          All other provisions of the Plan remain unchanged.

4.          The preamble shall form a part of this agreement as if recited
herein at length.
<PAGE>
                                      -2-


5.          Les parties aux presentes ont exigees que cette convention soit
redigee en anglais; the parties hereto have required that this agreement be
written in English.

IN WITNESS WHEREOF, the parties have signed, this      day of February, 1997.



                                        CLINTRIALS BIORESEARCH LTD.


                                        Per: /s/ W. O'Neil
                                            ------------------------------



                                        BIO-RESEARCH LABORATORIES LTD.



                                        Per: /s/ M. Ankcorn
                                            ------------------------------



                                        PwC



                                        /s/ Norah K. Taylor
                                        ---------------------------------
                                        NORAH K. TAYLOR
<PAGE>
MEMORANDUM OF AGREEMENT entered into at Montreal, the 30th day of December, 1983


AMONGST:                                CDC LIFE SCIENCES INC., a corporation
                                        duly constituted according to law,
                                        having an office and place of business
                                        in the City of Toronto, Province of
                                        Ontario, herein acting and represented
                                        by MICHAEL ANKCORN, one of its
                                        directors, duly authorized as he so
                                        declares (hereinafter called "CDC")


AND:                                    BIO-RESEARCH LABORATORIES INC., a
                                        corporation duly constituted according
                                        to law, having an office and place of
                                        business in the Town of Senneville,
                                        Province of Quebec, herein acting and
                                        represented by MICHAEL ANKCORN, its
                                        president, duly authorized as he so
                                        declares (hereinafter called the
                                        "Laboratories")

                                        (CDC and Laboratories are sometimes
                                        hereinafter called the "Employers")


AND:                                    STUART H. COBBETT, advocate, residing at
                                        422 Roslyn Avenue, Westmount, Quebec,
                                        H3Y 2T5 (hereinafter called the
                                        "Custodian")


            WHEREAS the Employers wish to create an Employee Benefit Plan, as
such expression is defined in the Income Tax Act of Canada, for the benefit of
certain of their employees;


            NOW THEREFORE THE PARTIES HERETO AGREE AS FOLLOWS:


1.          Definitions

            As used in this agreement, the following words and phrases shall
have the meanings set forth below:

      a)    "Contributions" shall mean the contributions made from time to time
            by the Employers or either one of them to the Custodian, pursuant to
            this agreement, for the account of one or more Employees;

      b)    "Distribution Date" with respect to any particular Employee shall
            mean the earliest of:
<PAGE>
                                                                              2.

            i)    the date on which such Employee ceases to be an employee of
                  the Employers or either one of them;

            ii)   the date of the death of such Employee; or

            iii)  such other date prior to the dates stipulated in subparagraphs
                  i) or ii) above as the Custodian, in his sole and absolute
                  discretion, may determine.

      c)    "Employees" shall mean the individuals listed in Schedule "A"
            hereto, as the same may be amended from time to time by way of
            supplemental agreement between the Employers and the Custodian, and
            who shall have signified their acceptance of the terms and
            conditions of this agreement; "Employee" shall mean anyone of such
            individuals;

      d)    "Employee's Pro Rata Share", with respect to any particular
            Employee, shall mean the amount of the Funds which bears the same
            proportion to the aggregate of the Funds as the Contributions
            allocated to the account of such Employee by the Custodian pursuant
            to articles 3.5 and 3.6 bears to the aggregate of the Contributions;

      e)    "Employee's Pro Rata Income", with respect to any particular
            Employee, shall mean that amount of the Net Annual Income which
            bears the same proportion to the aggregate Net Annual Income as the
            aggregate of the Contributions allocated to the account of such
            Employee by the Custodian hereof bears to the aggregate of the
            Contributions, subject however to article 4.2;

      f)    "Funds" shall mean all Contributions held by the Custodian pursuant
            to this agreement, and any property which the Custodian may purchase
            with or obtain in exchange or in replacement of the said
            Contributions or Funds, as well as property representing the same;

      g)    "Income" shall mean all the income received by the Custodian which
            arises or is derived from the Funds as well as all Income arising or
            derived from the investment of any such Income;

      h)    "Net Annual Income" shall mean the Income for a calendar year less
            all expenses incurred during such period in earning same, including
            expenses provided for hereunder;

      i)    "Plan" shall mean the Employee Benefit Plan constituted under this
            agreement;

      j)    "Specified Corporation" shall mean a corporation a majority of the
            voting shares of which are beneficially owned by an Employee;


2.          Purpose

2.1         This Plan is created for the sole purpose of benefiting the
Employees, in accordance with its terms. Save as may be expressly provided
herein, in no event shall any part
<PAGE>
                                                                              3.


of the Funds or the Income be paid to the Employers or be used for any purpose
whatsoever other than the exclusive benefit of the Employees.

2.2         The Plan constituted hereunder and the Contributions made by the
Employers are and remain irrevocable and for greater certainty, it is hereby
declared that the Employers have no right to intervene in the administration or
decisions of the Custodian hereunder. The Custodian shall hold such
Contributions and the Funds on behalf of the Employees.


3.          Contributions

3.1         The Employers or either one of them may, from time to time, make
Contributions to the Plan at such time, in such amount and in such manner as
they deem appropriate. Nothing herein contained shall be construed so as to
require an Employer to make arty Contributions.

3.2         All Contributions shall be made to the Custodian in lawful currency
of Canada, in cash or by cheque, and not in kind.

3.3         Contributions made to the Custodian shall be subject to the terms
and conditions herein set forth and held by him in accordance with such terms
and conditions.

3.4         Contributions may be made for the benefit of any one of the
Employees or such of them as the Employer making same shall specify in writing
to the Custodian at the time of making such Contribution(s).

3.5         The Custodian shall maintain a separate account in the name of each
Employee and shall credit all Contributions made for the benefit of the Employee
to his account.

3.6         Any Contribution made to the Custodian by an Employer, which is not
specified at such time as it is made to have been made for the benefit of one or
more of the Employees, shall be deemed to have been made for the benefit of all
the Employees and shall be allocated by the Custodian equally to the accounts of
all of them.


4.          Allocation and Payment of Benefits

4.1.        The Custodian shall invest and keep invested the Funds in accordance
with all the terms hereof. As of December 31 of each year, all Income for such
year shall be credited, and all expenses shall be charged, to the various
accounts maintained by the Custodian for the Employees. Subject to the
provisions of article 4.2, such credit and charges shall be made to each
Employee's account in accordance with the Employee's Pro Rata Share.

4.2         Notwithstanding the provisions of article 4.1, should the
Contributions allocated to the account of an Employee be used by the Custodian
to purchase shares of a Specified Corporation of the Employee, then the amount
of the Contributions used to purchase such shares shall be deducted from both
the Contributions allocated to such Employee's account and the aggregate of the
Contributions for purposes of calculating the Employee's Pro Rata Income.

4.3         The Custodian shall pay the Employee's Pro Rata Income determined in
accordance with the provisions of articles 4.1 and 4.2 above, in such manner as
he shall in his
<PAGE>
                                                                              4.


absolute discretion consider advisable from time to time, but in any event
before December 31 of any calendar year in which such Income is received.

4.4         Within one hundred and twenty (120) days (the "Distribution Period")
following the relevant Distribution Date, the Custodian shall make over,
transfer and deliver to an Employee or in the event of his death, to his legal
representatives, one half of the Employee's Pro Rata Share and the Employee's
Pro Rata Income to which he may be entitled, in full and complete ownership;
payment of the balance of the Employees's Pro Rata Share and (if any) of the
Employees's Pro Rata Income shall be made not later than the thirtieth business
day of the calendar year following the year in which the payment of the said
one-half was made. The Custodian shall have the right, in his sole and absolute
discretion, to pre-pay in whole or in part all or any amounts owing to the
Employee. Upon payment of all amounts to the Employee, the Custodian shall have
no further obligations to such Employee. Provided always, however, that in the
event of death of an Employee, the Distribution Period shall be extended, if
necessary, until 30 days following the date upon which the Custodian shall have
received all necessary clearances and/or certificates under relevant tax
(including succession duty) legislation.

4.5         Notwithstanding anything herein contained, the Custodian may, in his
sole and absolute discretion, at any time and from time to time before the
Distribution Date, pay to an Employee a part of the Employee's Pro Rata Share.

4.6         Notwithstanding anything herein contained, in the event that all or
any part of the Contributions allocated to the account of an Employee by the
Custodian shall have been used by the Custodian to purchase shares in the
capital stock of the Specified Corporation of the Employee, then, at the
Distribution Date, the Custodian may, in his sole and absolute discretion,
discharge the payment of all or any part of the Employee's Pro Rata Income by
delivery of such shares. For the purpose of this agreement, the amount allocated
to the value of such shares at any time, and from time to time, including at the
Distribution Date, shall be the subscription price for such shares, irrespective
of any increase or decrease in the actual or market value of such shares.

4.7         The Custodian may make any payment for any person under the age of
eighteen (18) years to a parent or guardian of such person or to anyone to whom
the Custodian in his absolute discretion considers it advisable to make such
payment, and the receipt of such person shall be sufficient discharge to the
Custodian.

4.8         The Funds, or any part thereof, as well as the Income, shall not be
liable to seizure for any debts or obligations of any nature whatever incurred
by an Employee; and an Employee's Pro Rata Share and Employee's Pro Rata Income
may not be validly assigned, anticipated or otherwise affected by any Employee.

4.9         Subject to the provisions hereof, an Employee's Pro Rata Share and
an Employee's Pro Rata Income are the property of the Employee and are "propres"
and personal to each Employee, without regard to his matrimonial regime or to
the matrimonial regime which may hereafter apply to any Employee and to any
spouse of the Employee and shall not form part of any community of property or
partnership of acquests.

4.10        The Funds may be held collectively for all the Employees, with no
physical division thereof until such time as distribution is actually made by
the Custodian or may be held individually, with physical division, as the
Custodian shall, in his sole and absolute discretion, deem appropriate.
<PAGE>
                                                                              5.


5.          Powers of Custodian

5.1         Without intending hereby to limit the powers and authority which he
would otherwise have by law, the Custodian shall have the following powers and
authority which he may exercise in his sole and absolute discretion whenever and
as often as he shall deem advisable until the final distribution of the Funds
and the Income in accordance with the provisions hereof, without application to
or approval by any court and without the consent of the Employers or the
Employees:

      a)    To be seized of, realize, receive and recover the whole of the Funds
            and, subject to the provisions of subparagraph (b) hereof, to sell,
            lease, alienate, exchange or otherwise dispose of or deal with, the
            whole or any part or parts of the Funds, in such manner and at such
            prices or in exchange for such property, moveable or immoveable, and
            upon such terms and conditions as the Custodian shall, in his sole
            and, absolute discretion, see fit and proper;

      b)    To invest, reinvest and exchange the Funds and/or any part or parts
            thereof in property and investments of the following types:

            (i)   investments of the kind described in article 981(0) of the
                  Quebec Civil Code; and/or

            (ii)  shares or other securities of a Specified Corporation.

            The Custodian shall not be held responsible for any loss that may
            result from any such investment made by him in good faith.

      c)    To borrow money from time to time, with or without interest, from
            any person, for the purposes of this Plan, and should the Custodian
            deem it necessary or advisable, without security or upon hypothecary
            or any other security on any of the Funds, whether moveable or
            immoveable, real or personal; to receive the money so borrowed and
            to deal with such monies as property forming part of the Funds and
            to repay the capital of the monies so borrowed, with interest
            thereon, as applicable, out of the Funds, at such time and on such
            terms as may be contained in any deed or agreement of loan;

      d)    To make such expenditures as the Custodian shall deem appropriate,
            in his sole and absolute discretion, in connection with the repair,
            improvement, building or re-building of any property, moveable or
            immoveable, real or personal, forming part of the Funds and to
            charge to the Funds such expenditures as the Custodian alone shall
            consider just and proper;

      e)    To compromise, settle, discharge, waive or renounce any claim or
            claims at any time due to or by the Custodian hereunder, for such
            consideration or without consideration and upon such terms and
            conditions as the Custodian alone may, in his sole and absolute
            discretion, deem advisable and proper;

      f)    To release any property, in whole or in part, on which any hypothec,
            mortgage, lien or other charge is held by the Custodian hereunder,
            for such consideration or without consideration, as the Custodian
            alone may, in his sole and absolute discretion, deem advisable and
            proper;
<PAGE>
                                                                              6.


      g)    To sign any and all deeds, documents and other instruments in
            writing, of any nature whatsoever, which may at any time and from
            time to time be necessary or expedient in and about the execution of
            this agreement and the administration of the Funds, and generally to
            act with the fullest powers in the execution and administration of
            this Fund and of the Funds;

      h)    To vote in person or by proxy upon the securities held by him and to
            delegate his discretionary powers in respect thereof, to exercise
            options, conversions, privileges or rights to subscribe for or to
            purchase additional securities attaching or accruing to any
            securities held by him, and to make payment thereof from the Funds;
            to consent to or participate in dissolutions, reorganizations,
            amalgamations, mergers or sales affecting securities held by him
            and, in such connection, to delegate his discretionary powers and
            pay assessments, subscriptions and other charges from the Funds;

      i)    To deposit any cash balances in the hands of the Custodian at any
            time in any bank or trust company or other financial institution
            accepting deposits and generally to carry out any and all banking
            transactions, including withdrawals from any of the accounts
            maintained by the Custodian;

      j)    To engage in transactions with the Employers or with any Employee,
            provided that such transactions are on the same basis as might
            reasonably be negotiated with a third party;

      k)    To form, as applicable, separate shares or portions from the Funds,
            without the intervention or consent of any Employee being required;
            and the decision of the Custodian in respect of such separate shares
            or portions and the formation and the composition thereof shall be
            final and binding and the Custodian shall have the same powers,
            authority and discretion in respect of any property forming part of
            such separate shares or portions as he would have in respect of the
            Funds as a whole;

      l)    To make any election, determination or designation pursuant to the
            Income Tax Act of Canada and pursuant to any equivalent provincial
            tax legislation as the Custodian may, in his sole and absolute
            discretion, deem to be in the best interest of the Funds and the
            Employees;

      m)    To act without giving security for his administration in any place
            or country, notwithstanding anything to the contrary in any law of
            this or any foreign country.

5.2         The Custodian shall be entitled, in the event of the Funds, or any
portion thereof, becoming liable or subject to income tax, succession duties,
probate duties, probate fees, inheritance tax, estate taxes, or any similar
taxes, duties, fees or imposition to pay out of the Funds and/or the Income, the
amount of such taxes, duties, fees or imposition and for such purposes to sell
such portion of the investments representing the Funds as may be necessary and
to charge any monies so paid in such manner as he deems proper.

5.3         In order to make payment of the Employee's Pro Rata Share and/or the
Employee's Pro Rata Income, the Custodian considers it necessary to surrender,
demand payment of, or otherwise dispose of any investment before the term
thereof, then the Custodian
<PAGE>
                                                                              7.


shall have full power and authority so to act. He shall have no liability for
any loss of interest or capital in so acting.


6.          Administration of Custodian

6.1         The Custodian and his agents or attorneys shall not be liable for
any error in judgment but only for his willful defaults and misconduct. In
particular, and without in any way limiting the generality of the foregoing, the
Custodian shall not be liable for any payments if made in good faith and without
knowledge of the happening of an event or a change in conditions which would
affect such payments.

6.2         The Custodian shall be entitled to be reimbursed from the Funds for
reasonable disbursements incurred hereunder.

6.3         In respect of any investment effected by the Custodian hereunder,
the Custodian shall be, at all times, at liberty to register his holdings in his
own name or that of a nominee or nominees without the necessity of disclosing
either his capacity or the nature of the Plan.

6.4         The Custodian is authorized in the discharge of his duties to employ
such counsel, solicitors, investment advisers, accountants, valuators,
surveyors, brokers and other professional or expert advisers, as he deems
advisable and to determine the amount of their reasonable compensation and to
reimburse them for reasonable expenses incurred from the Funds, and shall be
entitled to act on the advice of or on the information obtained from such
persons.

6.5         The Custodian may further pay and discharge from and out of the
Income or the Funds appropriate fees as well as such reasonable and necessary
expenses incurred in connection with the investment of the Funds or any part
thereof.

6.6         The Custodian shall be entitled, while he continues to act as a
Custodian hereunder, to receive a reasonable remuneration for his services and
responsibility relating hereto. In addition, any Custodian being a banker,
solicitor, accountant or professional custodian or member of a firm or company
who or whose firm or company is employed or entitled to be paid for his or its
services, or for those of the firm or company, shall be entitled to payment for
the services rendered in connection with this agreement.

6.7         The Custodian in performing any act hereunder, shall be entitled to
rely upon any affidavit, certificate, letter, notice, telegram or other paper or
document believed by the Custodian to be genuine and upon any information or
evidence believed by the Custodian to be sufficient.


7.          Accounts

7.1         The Custodian shall keep or cause to be kept accurate and detailed
accounts of all investments, receipts and disbursements and other transactions
hereunder, and all accounts, books and records relating thereto shall be open to
inspection by any person designated by the Board of Directors of either of the
Employers at all reasonable times. Not later than one hundred and fifty (150)
days after the end of each calendar year and within one hundred and fifty (150)
days after the effective date of the removal or resignation of the Custodian,
the Custodian shall
<PAGE>
                                                                              8.


file or cause to be filed with the Employers a written report setting forth all
investments, receipts, disbursements and other transactions effected by the
Custodian from the date of the prior such report to the close of the calendar
year, or the date of removal or resignation of the Custodian, as the case may
be. Such report shall contain an exact description of all securities and
investments held at the close of the calendar year or the effective date of such
removal or resignation of the Custodian, as the case may be, and the cost of
each item thereof, as carried on the books of the Custodian. Upon the expiration
of one hundred and eighty (180) days from the date of filing such report, the
Custodian, including a custodian who has resigned or was removed, shall be
forever released and discharged from any liability or accountability to any one
as respects the propriety of the Custodian's acts or transactions shown on such
reports, except with respect to any such acts or transactions as to which the
Employers shall within such one hundred and eighty (180) days file with the
Custodian a written statement claiming fraud or bad faith on the part of the
Custodian; and neither the Employers nor any other persons shall have the right
to demand or be entitled to any further or different accounting by the
Custodian.

7.2         The accounts, books and records kept by the Custodian in accordance
with the provisions of article 7.1 hereof, may only be reviewed by an Employee
insofar as relates to the Employee's Pro Rata Share and the Employee's Pro Rata
Income and the Custodian shall not be required to disclose or make available to
any Employee the accounts, books and records or any other information in his
possession pertaining to the Pro Rata Share and Pro Rata Income of any other
Employee.


8.          Removal or Resignation of Custodian

8.1         The Custodian may be removed by resolution of the Board of Directors
of one of the Employers upon delivery to him of a certified copy of such
resolution. The Custodian may further resign as Custodian, upon notice to that
effect delivered to both the Employers. Such removal or resignation shall become
effective upon the date specified in such resolution or such notice, as the case
may be, which shall not be less than fifteen (15) days subsequent to the
delivery of such certified copy of resolution or such notice. A successor
Custodian, upon accepting such appointment, shall become vested with the same
powers, duties, privileges and immunities as if such Custodian had been
originally named in this Plan as a custodian. In case of the removal,
resignation, death or inability to serve as a Custodian, said Custodian, or his
personal representative, shall forthwith turn over to the succeeding Custodian
all accounts and records in such Custodian's possession and shall execute such
instruments as may be necessary to terminate his custody. No bond shall be
required of the Custodian named in this Plan or any of the Custodian's
successors.

8.2         Each successor Custodian may accept as complete and correct and may
rely upon any accounting which shall have been made by or on behalf of any
Custodian hereunder prior to the date upon which such successor Custodian shall
have qualified as a Custodian under this agreement, and may rely upon any
statement or representation made by any Custodian then or theretofore acting
hereunder as to the assets comprising the Funds or the Income or as to any other
fact bearing upon the prior administration of the Plan; and such successor
Custodian shall not be subject to any liability by reason of having accepted and
relied upon such accounting, statement or representation in case it is
subsequently established that the same was incomplete, inaccurate or untrue. No
successor Custodian hereunder shall be subject to any liability or
responsibility with respect to any act or omission of any other Custodian, nor
shall any successor Custodian have any duty to enforce or to see to enforce any
<PAGE>
                                                                              9.


claims of any kind against any predecessor Custodian on account of or in
connection with any act or omission of any Custodian hereunder.


9.          Termination of Plan

            The Plan and this agreement shall terminate at such time as all of
the Employee's Pro Rata Share and the Employee's Pro Rata Income shall have been
distributed to the Employees in accordance with the terms hereof, and after
payment of all expenses and adjustments deemed necessary by the Custodian, as
the Custodian in his sole and absolute discretion shall determine.


10.         Nature of Plan

10.1        It is intended that this Plan shall be construed so as to qualify as
and constitute an "Employee Benefit Plan" in accordance with the provisions of
the Income Tax Act of Canada.

10.2        It is hereby declared that this Plan and this agreement do not
constitute an "Employee Trust" as such term is defined in the Income Tax Act of
Canada.


11.         General

11.1        Save as set forth herein, no payments or distributions shall be
required to be made by the Custodian.

11.2        In the event that any provision or part of any provision hereunder
shall be held invalid by any court of competent jurisdiction, such provision or
part thereof shall be deemed to be severed from this deed and not to form part
thereof for the purposes only of the particular proceedings or judgment without
invalidating any other provisions hereof, which provisions shall remain in full
force and effect.

11.3        Words used in the singular include the plural and vice versa; the
masculine gender shall include the feminine and neuter genders and vice versa.

11.4        This agreement shall be governed by and construed in accordance with
the laws of the Province of Quebec.

11.5        The preamble to this agreement shall form part hereof as though
recited herein at length.

11.6        This agreement shall be binding upon and inure to the benefit of the
parties hereto and their respective executors, administrators, successors and
assigns.

11.7        The parties acknowledge that they have required that the present
agreement, as well as all documents, notices and legal proceedings executed,
given or instituted pursuant or relating directly or indirectly hereto, be drawn
up in English. Les parties reconnaissent avoir exige la redaction en anglais de
la presente convention, ainsi que de tous documents executes,
<PAGE>
                                                                             10.



avis donnes et procedures judiciaires intentees, directement ou indirectement, a
la suite de ou relativement a la presente convention.

            AND THE PARTIES HERETO have signed on the date and at the place
first hereinabove mentioned.

                                        CDC LIFE SCIENCES INC.
                                        Per:

                                        /s/ M. F. Ankcorn
                                        ---------------------------------


                                        BIO-RESEARCH LABORATORIES INC.
                                        Per:

                                        /s/ M. F. Ankcorn
                                        ---------------------------------




                                        /s/ STUART H. COBBETT
                                        ---------------------------------
                                        STUART H. COBBETT
<PAGE>
                                   SCHEDULE A









                               MICHAEL F. ANKCORN