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                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549
                                 FORM 20-F/A

(Mark One)

          [ ]  REGISTRATION STATEMENT PURSUANT TO SECTION 12(b) OR (g) OF THE
               SECURITIES EXCHANGE ACT OF 1934

                                       OR

          [X]  ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES
               EXCHANGE ACT OF 1934

For the fiscal year ended December 31, 1999

                                       OR

          [ ]  TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE
               SECURITIES EXCHANGE ACT OF 1934

For the transition period from ______________________ to __________________

Commission file number               0-29574
                       ------------------------------------------------------

                                  ALTAREX CORP.
             (Exact name of Registrant as specified in its charter)

                           Province of Alberta, Canada
                 (Jurisdiction of incorporation or organization)

                       303 Wyman Street, Waltham, MA 02451
                    (Address of principal executive offices)

Securities registered or to be registered pursuant to Section 12(b) of the Act:

Title of each Class                    Name of each exchange on which registered

     None
--------------------------------------------------------------------------------

Securities registered or to be registered pursuant to Section 12(g) of the Act:


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                         Common Shares without par value
                                (Title of Class)

Securities for which there is a reporting obligation pursuant to Section 15(d)
of the Act:

                                      None
                                (Title of Class)

Number of outstanding shares of each of the Company's classes of capital or
common stock as of May 15, 2000: 63,308,908 Common Shares

Indicate by check mark whether the registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days.

Yes  X     No ---
    ---
Indicate by check mark which financial statement item the registrant has elected
to follow.

Item 17  X     Item 18 ----
        ---
(APPLICABLE ONLY TO ISSUERS INVOLVED IN BANKRUPTCY PROCEEDINGS DURING THE PAST
FIVE YEARS)

Indicate by check mark whether the registrant has filed all documents and
reports required to be filed by Sections 12, 13 or 15(d) of the Securities
Exchange Act of 1934 subsequent to the distribution of securities under a plan
confirmed by a court.

Yes ___   No ___


AltaRex Corp. (the "Company") hereby amends its Annual Report on Form 20-F for
the year ended December 31, 1999 to include additional information set forth
under Item 10.

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ITEM 10 - DIRECTORS AND OFFICERS OF REGISTRANT AS OF MAY 15, 2000

<TABLE>
<CAPTION>
NAME AND MUNICIPALITY                    POSITION                         PRESENT OCCUPATION AND POSITION DURING
                                                                          THE LAST FIVE YEARS
------------------------------------------------------------------------------------------------------------------
<S>                                      <C>                              <C>
Dr. Antoine A. Noujaim                   Chairman of the Board and        President and Chief Executive Officer from
Edmonton, Alberta                        Chief Scientific Officer         November, 1995 to February 22, 1998;
                                                                          President of Biomira Research Inc., a
                                                                          division of Biomira Inc. (A
                                                                          biopharmaceutical company), from 1994 to
                                                                          1995; Senior Vice-President of the
                                                                          Immunoconjugate Division of Biomira Inc.
                                                                          from 1989 to 1994; director of Biomira
                                                                          Inc. from 1985 to 1995.

Richard E. Bagley(2)                     President, Chief Executive       President, Chief Executive Officer and
Weston, Massachusetts                    Officer and Director             Director since February 23, 1998.
                                                                          Chairman and Chief Executive Officer of
                                                                          Proscript Inc. from September, 1995 to
                                                                          February, 1998. President and Chief
                                                                          Executive Officer of Immulogic
                                                                          Pharmaceutical Corporation from 1990 to
                                                                          1994.

William R. McMahan(1) (2)                Director                         Director since July 15, 1996.
Calgary, Alberta                                                          President of Oxbow Capital Corporation
                                                                          and Oxbow Investment Inc. from October,
                                                                          1993 to present. A Director of International
                                                                          Marketing, Oxbow Research Limited from January,
                                                                          1992 to present. Chief Operating Officer and Director
                                                                          of Oxbow Equities Corporation. Director of
                                                                          UltraVision, Inc.

Monique Begin(1)                         Director                         Director since May 14, 1998. Professor
Ottawa, Ontario                                                           Emeritus, University of Ottawa. Dean,
                                                                          Faculty of Health Sciences, University
                                                                          of Ottawa from 1990 to 1997. Member of the Board of
                                                                          Directors of the National Cancer Institute of Canada.
                                                                          Former Minister of National Health and Welfare
                                                                          Canada from September 1977 to September
                                                                          1984.

Dr. Jim A. Wright(2)                    Director                          Director since May 14, 1998. President, Chief
Winnipeg, Manitoba                                                        Scientific Officer and Director of Lorus Therapeutics
                                                                          Inc. since October 1999. Previously, Chairman of
                                                                          the Board, President and Chief Scientific Officer of
                                                                          GeneSense Technologies Inc. since 1997 until its merger
                                                                          with Lorus. Terry Fox Senior Research Scientist of the
                                                                          National Cancer Institute of Canada since 1990. Associate
                                                                          Director, Manitoba Institute of Cell Biology since 1989.

Normand Balthazard(1) (2)                 Director                        Director since December 22, 1999.
Montreal, Quebec                                                          President and Chief Executive Officer of
                                                                          BioCapital Investments, Limited
                                                                          Partnership since 1990.

Edward M. Fitzgerald                     Senior Vice President, Chief     Senior Vice President, Chief Financial
Dover, Massachusetts                     Financial Officer and            Officer and Secretary since September
                                         Secretary                        28, 1998. Consultant in private
                                                                          practice, 1998. Director, Mergers &
                                                                          Acquisitions and Director, Consumer
                                                                          Lending Group at BankBoston Corporation
                                                                          from 1992 to 1997. With Arthur Andersen
                                                                          & Co. from 1978 to 1992 serving as
                                                                          Partner from 1989 to 1992.
</TABLE>


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<TABLE>
<CAPTION>
<S>                                      <C>                              <C>
Dr. Christopher F. Nicodemus             Senior Vice President,           Senior Vice President, Clinical Research
Charlestown, Massachusetts               Clinical Research and            and Development since January 25, 1999. Vice
                                         Development                      President, Medical Affairs from 1998 to 1999
                                                                          and Vice President, Clinical Operations
                                                                          from 1997 to 1998 of Diatide, Inc. With
                                                                          Immulogic Pharmaceutical Corporation from
                                                                          1993 to 1997 serving as Vice President,
                                                                          Medical Affairs from 1994 to 1997. Senior
                                                                          Associate Medical Director with Pfizer
                                                                          Labs from 1992 to 1993.

Marlene R. Booth                         Vice President, Regulatory       Vice President, Regulatory Affairs and
Norwell, Massachusetts                   Affairs and Project              Project Management since June 1, 1999.
                                         Management                       Vice President, Project Management, QA and
                                                                          Regulatory at Proscript, Inc. from 1997 to
                                                                          1999. Senior Director Regulatory Affairs
                                                                          at Biopure Corporation from 1995 to
                                                                          1997. Vice President, Regulatory Affairs
                                                                          and Quality Assurance from 1992 to 1994
                                                                          at Ares Serono.

Peter C. Gonze                           Senior Vice President,           Senior Vice President, Operations and
Sudbury, Massachusetts                   Operations and Investor          Investor Relations since February 2000.
                                         Relations                        Vice President, Investor Relations and
                                                                          Medical Marketing from October 1999 to
                                                                          February 2000. With MediSense Products,
                                                                          Abbott Laboratories as Divisional Vice
                                                                          President from 1996 to 1999. With The
                                                                          Griffin Group from 1994 to 1996.

Robert A. Newman                         Vice President,                  Vice President, Business Development
Maynard, Massachusetts                   Business Development             since February 2000.  Executive
                                                                          Director, Business Development from 1998
                                                                          to 2000. Director of Marketing from 1997
                                                                          to 1998. With Ligand Pharmaceuticals as
                                                                          Marketing Manager, Canada from 1995 to
                                                                          1997. With QLT Phototherapeutics as
                                                                          Marketing/Program Manager from 1994 to
                                                                          1995.
</TABLE>

Notes:

(1)  Member of Audit Committee.
(2)  Member of Compensation Committee.


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                                    SIGNATURE

Pursuant to the requirements of Section 12 of the Securities Exchange Act of
1934, the registrant certifies that it meets all of the requirements for filing
on Form 20-F and has duly caused this registration statement to be signed on its
behalf by the undersigned, thereunto duly authorized.

ALTAREX CORP.


Per:     /s/ Edward M. Fitzgerald
    ------------------------------------------
         Edward M. Fitzgerald
         Senior Vice President and
         Chief Financial Officer

DATED this 25th day of May, 2000.


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