ARIAD Announces Election of Mary Tanner, Senior Bear Stearns Investment Banker, to Its Board Of Directors.

Business Editors/Health/Medical Writers

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CAMBRIDGE, Mass.--(BUSINESS WIRE)--Sept. 22, 2003

ARIAD Pharmaceuticals, Inc. (Nasdaq: ARIA) today announced the election of Mary Tanner, senior managing director at Bear Stearns & Co. Inc. and former managing director and head of the healthcare practice at Lehman Brothers, Inc., to its Board of Directors. During her twenty-five year tenure on Wall Street, Ms. Tanner has worked on or supervised more than 550 transactions with a total value of over $175 billion, including ten large pharmaceutical mergers. At Lehman, Ms. Tanner became the first woman partner of the firm. Ms. Tanner received her B.A. from Harvard University.

"Ms. Tanner's record of achievement and leadership are widely recognized in both the investment banking and pharmaceutical industries. Her breadth of experience and network of relationships will be invaluable to us as we make the strategic decisions that should lead ARIAD to becoming a profitable commercial enterprise," said Harvey J. Berger, M.D., chairman and chief executive officer of ARIAD.

ARIAD is engaged in the discovery and development of breakthrough medicines that regulate cell signaling with small molecules. The Company is developing a comprehensive approach to the treatment of cancer and is primarily focused on a series of product candidates for targeted oncology indications. ARIAD also has an exclusive license to pioneering technology and patents related to the discovery, development and use of drugs that regulate NF-(kappa)kB cell-signaling activity, which has been implicated in many major diseases.

Additional information about ARIAD can be found on the web at http://www.ariad.com.

Some of the matters discussed herein are "forward-looking statements" within the meaning of the Private Securities Litigation Reform Act of 1995. Such statements are identified by the use of words such as "anticipate," "estimate," "expect," "project," "intend," "plan," "believe," and other words and terms of similar meaning in connection with any discussion of future operating or financial performance. Such statements are based on management's current expectations and are subject to certain factors, risks and uncertainties that may cause actual results, outcome of events, timing and performance to differ materially from those expressed or implied by such forward-looking statements. These risks include, but are not limited to, risks and uncertainties regarding the Company's ability to conduct preclinical and clinical studies of its product candidates and the results of such studies, regulatory oversight, intellectual property claims, the timing, scope, cost and outcome of legal proceedings, future capital needs, key employees, dependence on the Company's collaborators and manufacturers, markets, economic conditions, products, services, prices, reimbursement rates, competition and other risks detailed in the Company's public filings with the Securities and Exchange Commission, including ARIAD's Annual Report on Form 10-K for the fiscal year ended December 31, 2002. The information contained in this document is believed to be current as of the date of original issue. The Company does not intend to update any of the forward-looking statements after the date of this document to conform these statements to actual results or to changes in the Company's expectations, except as required by law.