Exhibit 99.1


        EXTENSION OF LICENSE AGREEMENT TO UNITED THERAPEUTICS CORPORATION

EDMONTON, ALBERTA, CANADA, AUGUST 11, 2003 - ALTAREX CORP. (TSX: AXO, OTC:
ALXFF) (the "Corporation") is pleased to announce that it has entered into an
agreement with its major strategic partner, United Therapeutics Corporation
("United"), to expand the territory granted to United under the existing
Exclusive License Agreement to include Germany. The extension of the license
offers United entry into European market. United's existing license covers all
countries with the exception of countries of the European Union and certain
other countries covered by AltaRex's previous agreements with Dompe Farmaceutici
S.p.A, Genesis Pharma and Medison Pharma.

United has made an initial payment and has agreed on milestone payments in
consideration for this license of rights to Germany. It has also agreed to the
same royalty payment structure on sales of products in Germany, as has already
been agreed with respect to the United States and other countries, as provided
for in the Exclusive License Agreement. The Exclusive License Agreement grants
the right to United to sublicense, develop, make, have made, use, import,
market, provide, sell and have sold certain of AltaRex's products including
OvaRex, BrevaRex, ProstaRex and GivaRex among others.

AltaRex will continue to work with Dompe, Genesis and Medison for Italy, Spain,
Portugal, Switzerland, Austria, Ukraine, Hungary, Poland, Greece, Turkey,
Romania, Bulgaria, Egypt and the Middle East among others.

Dr. Antoine Noujaim, President and Chief Executive Officer commented, "I am very
pleased to have further synchronized global manufacturing and marketing efforts
for the Corporation's products with United, our major strategic partner. AltaRex
intends to continue collaborating with United on future development of licensed
products."

Dr. Martine Rothblatt, Chairman and Chief Executive Officer of United, said, "I
am pleased that United Therapeutics is able to expand its territory for these
promising cancer therapies to include Europe's largest market."

AltaRex Corp. is focused on the research, development and commercialization of
foreign antibodies that modulate the immune system for the treatment of certain
cancers and other diseases where there exists any unmet medical need. Additional
information about AltaRex Corp. can be found on the Corporation's website at
www.altarex.com.

United Therapeutics is a biotechnology company focused on combating chronic and
life-threatening cardiovascular, infectious and oncological diseases with unique
therapeutic products.