Exhibit 99.1

                  ARIAD Announces Management Change

    CAMBRIDGE, Mass.--(BUSINESS WIRE)--Nov. 12, 2004--ARIAD
Pharmaceuticals, Inc. (Nasdaq: ARIA) today announced that Paul Sekhri,
president and chief business officer, has resigned from the Company,
effective mid-December, to become chief executive of a start-up
specialty pharmaceutical company focused on lifestyle therapeutics.
    "I would like to thank Paul for his contributions to ARIAD over
the past year and wish him well in his new endeavor," said Harvey J.
Berger, M.D., chairman and chief executive officer of ARIAD. "We are
currently recruiting a number of key senior executives to enhance our
operations and business development capabilities."

    About ARIAD

    ARIAD is engaged in the discovery and development of breakthrough
medicines to treat cancer by regulating cell signaling with small
molecules. The Company is developing a comprehensive approach to
patients with cancer that addresses the greatest medical need -
aggressive and advanced-stage cancers for which current treatments are
inadequate. ARIAD also has an exclusive license to pioneering
technology and patents related to certain NF-(kappa)B treatment
methods, and the discovery and development of drugs to regulate
NF-(kappa)B cell-signaling activity, which may be useful in treating
certain 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
accurately estimate the actual research and development expenses and
other costs associated with the preclinical and clinical development
of our product candidates, the adequacy of our capital resources and
the availability of additional funding, risks and uncertainties
regarding the Company's ability to successfully conduct preclinical
and clinical studies of its product candidates, risks and
uncertainties that clinical trial results at any phase of development
may be adverse or may not be predictive of future result or lead to
regulatory approval of any of the Company's product candidates, and
risks and uncertainties relating to 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, 2003. 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.
             Kelly Lindenboom, 617-621-2345