Exhibit 99.1

ARIAD Appoints Former Novartis Senior Executive as President and Chief
Business Officer

    CAMBRIDGE, Mass.--(BUSINESS WIRE)--Sept. 29, 2003--ARIAD
Pharmaceuticals, Inc. (Nasdaq: ARIA) today announced the appointment
of Paul J. Sekhri, former senior vice president in the global business
development and licensing group at Novartis Pharma AG, to the newly
created position of president and chief business officer of ARIAD. Mr.
Sekhri was head of global search and evaluation and head of global
early-commercial development at Novartis from 1999 through 2003. Most
recently, he was a partner at the Sprout Group, the venture capital
arm of Credit Suisse First Boston.
    At Novartis, Mr. Sekhri was a member of the top senior-management
decision-making teams. His department led the development and
implementation of Novartis' global disease area strategy. He also had
global responsibility for providing commercial and market input into
the development of new drugs emerging from research at Novartis.
    "I am delighted to have Paul working closely with me," said Harvey
J. Berger, M.D., chairman and chief executive officer of ARIAD. "He
brings close to twenty years of experience in the life-sciences to our
executive team, including business development and partnering, sales
and marketing, commercial strategy, and portfolio management. His
in-depth knowledge of the multinational pharmaceutical and
biotechnology markets and products, coupled with his skills in
structuring and negotiating innovative business partnerships, will
help ARIAD achieve its corporate objectives."
    Prior to joining Novartis, Mr. Sekhri held management positions at
several life-sciences companies, including Millipore Corporation,
PerSeptive Biosystems, Inc. and Zymark Corporation, and the consulting
company, Northeast Consulting Resources, Inc. Mr. Sekhri has a B.Sc.
and M.Sc. from the University of Maryland.

    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)B 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.

    CONTACT: ARIAD Pharmaceuticals, Inc.
             Tom Pearson, 610-407-9260
             or
             Kathy Lawton, 617-621-2345