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                                                                    EXHIBIT 4.28

                                                               DR. MARTIN BARKIN
                                                               President and CEO
                                                            Mississauga Location
                                    Tel: (905) 677-0898 #236 Fax: (905) 677-5494
                                                        Cellular: (416) 726-8870
                                                              mbarkin@draxis.com

March 26, 2004

PERSONAL & CONFIDENTIAL

Mr. John E.M. Durham
102 Mayfair
Hudson, Quebec  J0P 1H0

RE: EMPLOYMENT AGREEMENT

Dear John:

By this letter we hereby confirm that your employment agreement with Draxis
Health Inc. dated April 22, 2003 (the "Employment Agreement") is amended as
follows:

  -  By deleting the fourth paragraph of Section 16 and replacing it with the
     following :

     Furthermore, you specifically agree that you shall respect and comply with
     by the DRAXIS's Disclosure Policy, as amended from time to time, copy
     thereof provided herewith as Schedule "C" to form an integral part of this
     Agreement, the DRAXIS's Code of Ethics as amended from time to time, copy
     thereof provided herewith as Schedule "D" to form an integral part of this
     Agreement, and all and any relevant rules and legislation, such as, without
     limiting the generality of the foregoing, the rules on Insider Trading in
     the TSX COMPANY MANUAL, the ONTARIO SECURITIES ACT, the CANADIAN BUSINESS
     CORPORATIONS ACT and QUEBEC SECURITIES ACT. You acknowledge that your
     senior position with DRAXIS will deem you an insider of DRAXIS and
     therefore subject to applicable mandated insider regulatory and company
     share trading policies and restrictions.

  -  By deleting Section 18(d) and replacing it with the following Section
     18(d):

     (d)   TERMINATION PAYMENT FOLLOWING A CHANGE OF CONTROL

     (1)   In accordance with section 18(d) (2) below, if there is a Change of
Control (as hereinafter defined) you shall be entitled to the following:

     A.   the amounts of any unpaid Base Salary earned up to and including date
          of termination;
     B.   any unpaid vacation pay earned up to and including date of
          termination;
     C.   a lump sum amount, equal to: (A) two times your then current Base
          Salary in effect immediately prior to the date of the Change of
          Control;
     D.   any additional statutory obligations imposed by the ACT RESPECTING
          LABOUR STANDARDS;
     E.   the right to exercise all stock options and other securities including
          those not then otherwise exercisable as provided for below.

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                                                                  MARCH 26, 2004
                             PERSONAL & CONFIDENTIAL                 JOHN DURHAM
                                                                          PAGE 2

     The payments referred to in paragraph 18(d), above, shall be guaranteed and
shall not be subject to set off or deduction as a result of your obtaining
alternate employment following termination or otherwise mitigating any damages
arising from termination. Further, notwithstanding paragraph 18(d) (1) (D)
above, the payment referred to in paragraph 18(d) (1) (C) above, is inclusive of
all statutory payments, including statutory termination and severance, which may
be owed to you following termination.

     The amounts paid to you pursuant to this paragraph shall be subject to all
required deductions.

     For the purposes of this Agreement, a Change of Control shall be deemed to
occur in the following circumstances.

     In the event that at any date following the date of signature hereof:

        (i)       any change in the ownership as of the date hereof, direct or
        indirect, of the outstanding shares of the Corporation as a result of
        which an individual, partnership, association, trust, unincorporated
        organization, ("Person") or group of Persons, hold shares and/or other
        securities in excessive of the number which, directly or following
        conversion or exercise thereof, will entitle the holders thereof to cast
        20% or more of the votes attaching to all such shares and/or other
        securities of the Corporation which may be cast to elect the directors
        of the Corporation; or

        (ii)   the sale, transfer or any manner of disposition of 50% or more of
               the assets of the Corporation to an arm's length Person;

     and the Board of Directors of the Corporation (the "Board of Directors")
recommends acceptance of such offer to the Shareholders of the Corporation (the
"Shareholders") or, if the Board of Directors has made no recommendation, the
Shareholders have approved or accepted the proposed transaction, then any
option, including options not then otherwise exercisable held by the you, shall
become immediately exercisable upon the issuance of the recommendation of the
Board of Directors or the approval or acceptance of the Shareholders, as the
case may be.

     For greater clarity, no provision in this employment agreement shall be
deemed to supersede any provision of the Stock Option Plan of DRAXIS, as amended
from time to time, with respect to the right to exercise options held by the
employee in certain circumstances.

     (2)   Except for the ability to exercise all stock options upon a Change of
Control as provided in paragraph 18(d)(1)(E), the payments and entitlements
outlined in paragraph 18(d) (1) shall become due and payable if, and only if:

     A.   there has been a Change of Control; and
     B.   within 12 months following any Change of Control:
          (i)  your employment is terminated without cause by DRAXIS or by any
               successor employer to DRAXIS, as the case may be; or
          (ii) by its conduct as described below, DRAXIS or any successor
               employer to DRAXIS, as the case may be, constructively terminates
               your employment by:
                    -  relocating without just cause the position and/or
                       location of your principal

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                                                                  MARCH 26, 2004
                             PERSONAL & CONFIDENTIAL                 JOHN DURHAM
                                                                          PAGE 3

                       office more than 20 kilometers from the location of your
                       office on the date immediately prior to the Change of
                       Control, without your consent; or
                    -  materially reducing without just cause your title,
                       reporting relationship, responsibilities or authority
                       without your consent; or
                    -  reducing without just cause the salary paid to you by the
                       successor employer or terminating without just cause or
                       materially reducing without just cause the value of your
                       benefit programs, including, but not limited to, life
                       insurance benefits, accidental death and dismemberment
                       benefits, long term disability benefits, extended health
                       coverage and dental benefits, which are referred to in
                       Section 3 above;

     C.   and, you elect in writing to receive the payments outlined in
          Section 18(d)(1)

  -  By deleting Section 18(h) and replacing it with the following section
     18(h):

     (h)  NO FURTHER NOTICE OR COMPENSATION
     Upon termination of your employment under this Agreement, you shall not be
entitled to any further grants of stock options nor shall you be entitled to any
further participation in any other incentive plan of the DRAXIS Group other than
as specifically set forth in this agreement. For all purposes, "termination of
your employment" and "termination date" shall be the final day of employment
with DRAXIS, and shall not be deemed to include any period during which you may
be entitled to statutory notice, statutory termination pay or any contractual or
common law notice period and in particular, shall not be deemed to include the
notice period identified in Sections 18(c) (1) or 18(d) (1) (C).

All of the other terms and conditions of your Employment Agreement remain
unchanged. We would ask that you confirm your acceptance of this modification by
signing the duplicate of this letter.

If you have any questions concerning this modification, please do not hesitate
to communicate with the undersigned.

Regards,

DRAXIS HEALTH INC.

/s/ Martin Barkin

Per:  Dr. Martin Barkin
      President and CEO

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I hereby confirm having read the above mentioned modification to my employment
agreement dated April 22, 2003 and hereby confirm my acceptance of said
modification.

Signed this ______ day of ___________, 2004 at ________________________.


  /s/ John Durham
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JOHN DURHAM