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                                                             Exhibit 10(m)(viii)

                       AMENDMENT TO EMPLOYMENT AGREEMENT

                 AMENDMENT TO EMPLOYMENT AGREEMENT, by and between CN
Biosciences, Inc., a Delaware corporation (formerly Calbiochem- Novabiochem
International, Inc., the "Company"), and Ben Matzilevich (the "Employee"),
dated as of February 27, 1997.

                 WHEREAS, the Company and the Employee are parties to an
Employment Agreement, dated as of February 23, 1996 (the "Employment
Agreement"); and

                 WHEREAS, the Company and the Employee wish to amend the
Employment Agreement with respect to payment to the Employee in connection with
the termination of the Employee's employment under certain circumstances.

                 NOW, THEREFORE, in connection with the mutual covenants
hereinafter set forth and for other good and valuable consideration, the
parties hereto agree as follows:

                 Section 1.  Amendments to Employment Agreement.

                 Paragraph 8 of the Employment Agreement is amended by (A)
amending existing subparagraph (a)(iii) of such paragraph to read in its
entirety as follows:

                          "(iii) Without Cause (A) if within the 90-day period
         following the effective date of a "Change in Control" (as defined
         below) of the Company, by paying to the Employee salary continuation
         pay equal to the Employee's base salary in effect at the time of
         termination for a period equal to the greater of (i) 12 months from
         the date of such termination or (ii) the remaining term of this
         Employment Agreement or (B) if at any other time, by paying to the
         Employee salary continuation pay equal to the Employee's base salary
         in effect at the time of termination for the remaining term of this
         Employment Agreement.  If the Company shall decide not to renew this
         Employment Agreement, the ninety (90) day notification of the
         Company's intention not to renew prior to expiration of the initial or
         any subsequent annual term, shall serve as adequate termination notice
         and the Employee hereby agrees to make a smooth transition of
         responsibilities during that ninety (90) day period and the Employee
         further agrees not to take any legal action against the Company
         related to said non-renewal and termination of employment.";

(B) adding a new subparagraph (b) to such paragraph to read as follows:


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                          "(b) In the event that the Employee resigns during
         the 90-day period following the effective date of a Change of Control
         of the Company, the Employee shall receive salary continuation pay
         equal to the Employee's base salary in effect at the time of the
         Change in Control for the period of 12 months from the date of such
         termination.";

(C) adding a new subparagraph (c) to such paragraph to read as follows:

                          "(c) For purposes of this Employment Agreement,
         "Change of Control" shall mean (a) an acquisition (other than directly
         from the Company) by an individual, entity or a group (excluding the
         Company, an employee benefit plan of the Company or E.M. Warburg,
         Pincus & Co., LLC or its affiliates) of 50% or more of the Company's
         Common Stock, par value $.01 per share, or voting securities; (b) a
         change in a majority of the Company's current Board of Directors (the
         "Incumbent Board") (excluding any persons approved by a vote of at
         least a majority of the Incumbent Board or persons elected with the
         concurrence of a majority of the Incumbent Board); or (c) the
         consummation of a complete liquidation or dissolution of the Company
         or a merger, consolidation or sale of all or substantially all of the
         Company's assets (collectively, a "Business Combination") other than a
         Business Combination in which all or substantially all of the
         Company's stockholders receive 50% or more of the stock of the Company
         resulting from the Business Combination, at least a majority of the
         board of directors of the resulting corporation were members of the
         Incumbent Board, and after which no Person owns 50% or more of the
         stock of the resulting corporation, who did not own such stock
         immediately before the Business Combination."; and

(C) renumbering existing subparagraph (b) of such paragraph to become
subparagraph (d).

                 Section 2.  Governing Law.  This Agreement shall be governed
by and construed and enforced in accordance with the laws of the State of
California without giving effect to the choice of law or conflict of laws
provisions thereof.

                 Section 3.  Entire Agreement.  This Agreement contains the
entire agreement of the parties with respect to the subject matter herein and
supersedes any and all agreements or understandings, written or oral, between
the Employee and the Company or any of the Company's principal stockholders,
affiliates or subsidiaries.  This Agreement may be changed only by an agreement
in writing signed by each of the parties hereto.



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                 IN WITNESS WHEREOF, the parties have executed this Agreement
as of the day first hereinabove written.



                                       CN BIOSCIENCES, INC.

                                       By:    /s/ Stelios B. Papadopoulos
                                          -------------------------------------
                                          Name:   Stelios B. Papadopoulos
                                          Title:  Chief Executive Officer
                                                  and President

                                       EMPLOYEE

                                       /s/ Ben Matzilevich                      
                                       ----------------------------------------
                                           Ben Matzilevich





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