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                                                                    Exhibit 1.18

June 1, 1999



Richard E. Bagley
121 Chestnut Street
Weston, MA
02493

Dear Dick:

RE: AMENDMENT TO THE TERMS OF YOUR EMPLOYMENT AS SET OUT IN THE LETTER DATED
FEBRUARY 18, 1998 (THE "LETTER AGREEMENT") FROM ALTAREX CORP. (THE "COMPANY") TO
YOU.

This letter serves as an amendment to the terms of your employment as set out in
the Letter Agreement. You and the Company agree that the paragraph in the Letter
Agreement related to severance compensation be and hereby is deleted in its
entirety and that the following paragraph shall be inserted in lieu thereof:

If your employment is terminated by the Company without just cause prior to
December 31, 2001, you will be entitled to receive severance payments at a
monthly rate equal to 1/12 of the annual base salary to which you were entitled
on the effective date of termination until the later of (a) December 31, 2001
and (b) the first anniversary of the effective date of termination. For purposes
of applying the foregoing, just cause for termination shall be deemed to exist
upon a) a good faith finding by the Company of your failure to perform your
assigned duties for the Company, dishonesty, gross negligence or misconduct, or
b) conviction, or the entry of a pleading of guilty or nolo contendere, to any
crime involving moral turpitude or any felony. Notwithstanding the foregoing, in
the event that you breach the Invention, Non-disclosure and Non-compete
Agreement dated as of May 18, 1998 between you and the Company at any time
during the period during which the Company is making severance payments to you
under this Agreement, the Company's obligation to make, and your entitlement to
receive, such severance payments under this Agreement shall terminate
immediately upon such breach.

All other terms of your employment as set out in the Letter Agreement remain in
full force and effect.


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Please confirm that you are in agreement with the foregoing by signing below. If
you have any questions, please contact me.

Sincerely,

 /s/ Antoine A. Noujaim
-------------------------
Antoine A. Noujaim, Ph.D.
Chairman of the Board and CSO


The parties hereto have executed this agreement of the 4th day of June,
1999.

                                           AltaRex Corp.

 /s/ Richard E. Bagley                      /s/ Antoine A. Noujaim
-------------------------                  ----------------------------
Richard E. Bagley                          Antoine A. Noujaim
                                           Chairman of the Board and Chief
                                             Scientific Officer
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Richard E. Bagley
121 Chestnut Street
Weston, MA  02493

Dear Richard:

RE: AMENDMENT TO THE TERMS OF YOUR EMPLOYMENT AS SET OUT IN THE LETTER DATED
FEBRUARY 18, 1998 (THE "LETTER AGREEMENT") AND THE AMENDMENT DATED JUNE 1, 1999


This letter serves as an amendment to the terms of your employment as set out in
the Letter Agreement as amended. Provisions for severance compensation as stated
in the June 1, 1999 amendment are further amended by deleting the first sentence
of such amended provision and inserting the following sentence:

     If your employment is terminated by the Company without just cause, you
     will be entitled to receive severance payments at a monthly rate equal to
     1/12 of the annual base salary to which you were entitled on the effective
     date of termination until the first anniversary of the effective date of
     termination.

All other terms of your employment as set out in the Letter Agreement and
Amendments remain in full force and effect.

Please confirm that you are in agreement with the foregoing by signing below. If
you have any questions, please contact me.

Sincerely,

 /s/ Edward M. Fitzgerald
----------------------------
Edward M. Fitzgerald
Senior Vice President & CFO


The parties hereto have executed this agreement on the 22nd day of December,
1999.

                                               AltaRex Corp.

 /s/ Richard E. Bagley                          /s/ Edward M. Fitzgerald
---------------------------------              ------------------------------
Richard E. Bagley                              Edward M. Fitzgerald