News Release

INEX Makes Milestone Payment to Elan


For immediate release: May 21, 2004

VANCOUVER – Inex Pharmaceuticals Corporation (“INEX”; TSX: IEX) announced today that the acceptance of the Onco TCS New Drug Application (NDA) by the US Food and Drug Administration (FDA) triggered the Company’s obligation to make a US$2.5 million payment to its former joint venture collaborator, Elan Corporation, plc (“Elan”; NYSE: ELN). INEX, at its discretion, can make this payment in cash or shares of INEX.

On April 3, 2003, INEX reacquired the 19.9% equity interest in Onco TCS held by Elan.  The terms of the agreement reached in April 2003 with Elan required INEX to make milestone payments to Elan totaling US$8 million.  INEX has made a previous US$3 million payment to Elan on the announcement of INEX’s partnership with Enzon Pharmaceuticals Inc. (“Enzon”; NASDAQ: ENZN) for the development of Onco TCS in North America. INEX is required to make one final payment of US$2.5 million to Elan upon FDA approval of Onco TCS.  After the final payment is made, INEX will have no further milestone or royalty obligations to Elan.  The final payment can be made in cash or shares of INEX.

The news release announcing the acceptance of the NDA can be found on INEX’s website at www.inexpharm.com.

About INEX
INEX is a Canadian biopharmaceutical company developing and commercializing proprietary drugs and drug delivery systems to improve the treatment of cancer.

There are forward-looking statements contained herein that are not based on historical fact, including without limitation statements containing the words “believes,” “may,” “plans,” “will,” “estimate,” “continue,” “anticipates,” “intends,” “expects,” and similar expressions.  Such forward-looking statements involve known and unknown risks, uncertainties and other factors that may cause the actual results, events or developments to be materially different from any future results, events or developments expressed or implied by such forward-looking statements.  Such factors include, among others, INEX’s stage of development, lack of product revenues, additional capital requirements, risks associated with the completion of clinical trials and obtaining regulatory approval to market INEX’s products, the ability to protect its intellectual property and dependence on collaborative partners.  These factors should be considered carefully and readers are cautioned not to place undue reliance on such forward-looking statements.  The Company disclaims any obligation to update any such factors or to publicly announce the result of any revisions to any of the forward-looking statements contained herein to reflect future results, events or developments.

INEX investor contact:
Ian Mortimer
Senior Director, Investor Relations
Inex Pharmaceuticals Corporation
Tel: 604.419.3200
Email: info@inexpharm.com
Website: www.inexpharm.com

INEX media contact:
Miriam Zitner
James Hoggan & Associates Inc.
Tel: 604.739.7500
Email: mzitner@hoggan.com