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                                                                Exhibit 10(viii)
                                                                ----------------


                                                 December 18, 1996

Dr. Jack Barbut
c/o Piper & Marbury LLP
1251 Avenue of the Americas
New York, New York 10022

Dear Jack:

This letter sets forth our agreement with respect to your employment with DNX
Corporation and any subsidiary or affiliate thereof (collectively referred to
herein as the "Company" and individually referred to herein as a "Protected
Party") and special separation benefits relating to the termination thereof, as
follows:

     1. POSITIONS, DUTIES AND PLACE OF PERFORMANCE: Your employment will
commence effective as of the closing of the acquisition of BioClin (Europe) AG
by the Company (the "Effective Date"). During the term of this agreement (unless
earlier terminated as provided below), you will devote substantially your full
time and attention to the operations and affairs of the Company with such duties
and responsibilities as the Chief Executive Officer of DNX Corporation may
reasonably determine; provided, however, that such duties and responsibilities
shall be consistent with being the Vice Chairman and President - Clinical
Services of the Company as well as President of BioClin Institute of Clinical
Pharmacology GmbH; and provided, further, that if the duties and
responsibilities are changed so they are not consistent with being the President
Worldwide Clinical Services, such duties and responsibilities as you and the
Chief Executive Officer may mutually agree within 30 days, and if no mutual
agreement is reached, you may treat such change of duties and responsibilities
as a termination of your employment by the Company pursuant to paragraph 4
below. You will perform your duties and responsibilities at the Company's
facilities in Raritan, New Jersey, except for travel required for Company
business. During the term of this agreement, the Company will not change the
primary place of performance of your duties and responsibilities without your
consent.

     2. COMPENSATION: During the term of this agreement (unless earlier
terminated as provided below), you will be paid in the United States at the
annualized rate of U.S. $140,000, or such greater amount as may be authorized by
the Compensation Committee (the "Compensation Committee") of the Board of
Directors of DNX Corporation (the "Board"). Such compensation shall be paid in
accordance with the normal procedures of the Company and the Compensation
Committee for compensating the Company's domestic employees and shall be subject
to withholding for applicable taxes and governmental charges. As soon as
practicable after the Effective Date, you will provide to the Company a
withholding certificate and such other written representations regarding your
status under United States and Swiss tax law as the Company may

                                


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Dr. Jack Barbut
December 18, 1996
Page 2

require, and the Company will be entitled to rely in good faith on such
certificate and representations.

     3.   Benefits:
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     (a)  IN GENERAL: During the term of this agreement (unless earlier
          terminated as provided below): you will be eligible to participate in
          such medical, dental, life and disability benefit programs as may be
          established by the Company; you will be eligible beginning in 1997 to
          participate in the DNX Corporation Executive Bonus Plan at the same
          levels as other senior executives of the Company, as authorized by the
          Compensation Committee; and you will receive a grant under the DNX
          Corporation 1996 Stock Option Plan of options to purchase 50,000
          shares of DNX Corporation common stock, on the same terms and subject
          to the same vesting requirements as the Compensation Committee shall
          determine for other senior executives of the Company.

     (b)  RELOCATION TO NEW JERSEY: During the term of this agreement (unless
          earlier terminated as provided below), the Company will pay or
          reimburse you for reasonable and necessary expenses incurred by you in
          connection with your relocation to New Jersey, including, without
          limitation, brokers' commissions, up to twelve months of temporary
          housing costs, closing costs, and costs of moving household belongings
          and automobiles.

     (c)  SPECIAL RETIREMENT BENEFITS: During the term of this agreement (unless
          earlier terminated as provided below), the Company will pay on your
          behalf to the Swiss social security system the lesser of (i) the
          annual amount necessary to maintain your retirement coverage as
          currently in effect under such system and (ii) the maximum annual
          amount of tax that the Company would be required to pay under section
          3111(a) of the Internal Revenue Code (or any successor provision
          thereto) with respect to your covered wages under section 3121(a) of
          the Internal Revenue Code and section 230 of the Social Security Act
          (or any successor provisions thereto) if your compensation hereunder
          were subject to such tax.

     (d)  AUTOMOBILE EXPENSES. During the term of this agreement (unless earlier
          terminated as provided below), the Company will pay or reimburse you
          $600 per month for the lease, insurance, maintenance and repair of an
          automobile.

     (e)  VACATION. During the term of this agreement (unless earlier terminated
          as provided below), you will be entitled to take 25 days of vacation
          per year in accordance with the Company's vacation policies in effect
          from time to time for senior executives.

                                


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Dr. Jack Barbut
December 18, 1996
Page 3

     4. SEVERANCE OBLIGATIONS: If your employment is terminated by the Company
(or is treated as terminated by the Company under section 1) during the term of
this agreement for any reason other than Cause, then, subject to sections 5, 6
and 7 below, the Company will provide to you:

     (a)      regular severance payments at the rate of your annualized
              compensation for employment at the time of termination until 12,
              24 or 36 months after your termination date, as elected in writing
              by the Company at the time of such termination. The period of
              severance elected by the Company for purposes of this agreement
              will be coextensive with any period of severance elected for
              purposes of your agreement to provide services as an independent
              contractor to BioClin AG. Any payments made will be reduced by
              applicable taxes and other required withholdings; and

     (b)      continuation of medical and dental insurance coverage until the
              earlier of (1) the date you obtain other full-time employment or
              (2) the date your salary continuation ceases.

For the purposes of this agreement, the term "Cause" means your (a) commission
of an act that is determined by the Board to be fraudulent or dishonest conduct
or a material breach of any of the Company's policies, (b) conviction of a
felony or knowing violation of any federal, state, or local law applicable to
the Company or (c) intentional refusal, without proper cause, to substantially
perform your duties after a demand for substantial performance has been
delivered to you in writing by your supervisor(s). Upon termination for Cause,
the Company shall have no further liability or obligation to you, except for
salary earned but not paid and other obligations mandated by law.

     5. RELEASE: In consideration for the special separation benefits set forth
in section 4 above, you shall agree to the conditions outlined on the attached
Release. The Company's severance obligations under section 4 above are expressly
conditioned upon your (a) execution and delivery of the Release at the time of
your termination of employment and (b) not revoking the Release within the
revocation period described therein.

     6. COMPETITIVE ACTIVITY: In consideration for the special separation
benefits set forth in section 4 above, you agree that (a) if your employment is
terminated by the Company (or is treated as terminated by the Company under
section 1) during the term of this agreement for any reason other than Cause,
then you will not, without the prior written consent of the Board in its sole
discretion, engage in any Competitive Activity during the period of your salary
continuation under section 4 above and (b) if your employment is terminated by
you for any reason other than as provided in section 1 or by the Company for
Cause, then you will not, without the prior written consent of the Board in its
sole discretion, engage in any Competitive Activity until the later of (1) five
years after the date of this agreement or (2) two years after your termination
date. The Company's severance obligations under section 4 above are expressly
conditioned upon your satisfaction of your obligations under this section 6.

                                


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Dr. Jack Barbut
December 18, 1996
Page 4

For the purposes of this agreement, the term "Competitive Activity" means your
participation in the management, clinical or preclinical operations of any
business enterprise if (a) such enterprise engages in substantial and direct
competition with any Protected Party in North America or Europe, (b) such
enterprise's sales of any product or service competitive with any product or
service of a Protected Party amounted to at least 10% of such enterprise's net
sales for its most recently completely fiscal year, and (c) such Protected
Party's sales of said product or service amounted to at least 10% of its net
sales for its most recently completely fiscal year. Competitive Activity will
not include the mere ownership of less than 5.0% of any class of the outstanding
securities of any such enterprise and the exercise of rights appurtenant
thereto.

     7. NO SOLICITATION OR HIRING: In consideration for the special separation
benefits set forth in section 4 above, you agree that (a) for a period of three
years after your termination date, you will not, without the prior written
consent of the Board in its sole discretion, directly or indirectly induce or
attempt to induce any employee of any Protected Party to leave the employment of
such Protected Party or to accept any other employment or position and (b) for a
period of two years after your termination date, you will not, without the prior
written consent of the Board in its sole discretion, directly or indirectly hire
or cause to be hired any employee of any Protected Party. The Company's
severance obligations under section 4 above are expressly conditioned upon your
satisfaction of your obligations under this section 7.

     8. TERM OF AGREEMENT: This agreement shall have a two-year term commencing
on the Effective Date, provided that thereafter the term will automatically be
extended for successive one-year periods unless either party gives written
notice, not less than 90 days prior to the otherwise scheduled expiration of the
term, that it or he does not want the term to so extend.

     9. GOVERNING LAW: This agreement shall be governed by and construed in
accordance with the internal laws of the State of New Jersey without regard to
conflicts of law principles.

     10. ENTIRE AGREEMENT; MODIFICATION: This agreement and the attached Release
constitute the entire agreement between you and the Company relating to your
employment with the Company and the termination thereof and supersede all other
prior understandings or agreements relating to

                                


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Dr. Jack Barbut
December 18, 1996
Page 5

your employment with the Company and the termination thereof. This agreement may
not be modified or amended except by a writing signed by you and the Company.

                                    Sincerely,

                                    /s/ Paul J. Schmitt
                                    Paul J. Schmitt
                                    Chairman

/s/ Jack Barbut                       December 18, 1996
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Jack Barbut                                Date

Enclosure