Exhibit 99.1

          ARIAD Reports Its Lead Oncology Product, AP23573,
               Potently Blocks Brain Tumor Cell Growth;

          Presentation At Society for Neuro-Oncology Meeting

    CAMBRIDGE, Mass.--(BUSINESS WIRE)--Nov. 14, 2003--ARIAD
Pharmaceuticals, Inc. (Nasdaq: ARIA) today announced, for the first
time, results of studies conducted by the Cleveland Clinic Brain Tumor
Institute on its lead oncology product candidate, currently in
clinical trials. Low doses of AP23573 reduced by 40% the growth of
brain tumor cells, known as glioblastoma. Rarely cured by currently
available treatments, this form of brain cancer is one of the most
deadly cancers. Following diagnosis, median survival is approximately
one year.
    The potency and anti-tumor activity of AP23573 were even more
striking, because the reduction of tumor cell growth was achieved both
in brain cancer cells over-expressing the epidermal growth factor
(EGF) receptor - a known marker of tumor aggressiveness - and in brain
cancer cells without EGF receptor over-expression, suggesting broad
applicability for treating these tumors.
    "The latest studies on AP23573 underscore the therapeutic
potential of our lead oncology product candidate and support
accelerated phase 2 clinical trials in patients with solid tumors,
such as gliomas," said Harvey J. Berger, M.D., chairman and chief
executive officer of ARIAD.
    The small molecule, AP23573, was designed to treat solid tumors
and other cancers by inhibiting the critical cell-signaling protein
mTOR, which causes tumor shrinkage by novel mechanisms of action -
blockage of growth factor stimulation and cancer-cell starvation
through inhibition of nutrient utilization.
    The Cleveland Clinic team was led by Michael A. Vogelbaum, M.D.,
Ph.D, who will be presenting these findings tomorrow at the eighth
annual meeting of the Society for Neuro-Oncology. The abstract by
Jennifer L. Nelms, et al, "A novel mTOR inhibitor (AP23573) produces
cell loss and apoptosis in glioblastoma multiforme independent of EGFR
status," is available on the website of the Society for Neuro-Oncology
(http://www.soc-neuro-onc.org/meeting.htm).
    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