UPDATE: ARIAD Reports Discontinuation of Phase 2 EPIC Trial of Iclusig

ARIAD Pharmaceuticals, Inc.

today announced that it is discontinuing the Phase 3 EPIC (Evaluation of Ponatinib versus Imatinib in Chronic Myeloid Leukemia) trial of Iclusig^® (ponatinib) in patients with newly diagnosed chronic myeloid leukemia. ARIAD and the U.S. Food and Drug Administration mutually agreed that the trial should be terminated because arterial thrombotic events were observed in patients treated with Iclusig. This decision was made in the interest of patient safety based on a recent assessment of data in the clinical trial. “Our decision to stop the EPIC trial at this time is based on our current evaluation of the safety data in the trial since it was placed on partial clinical hold last week,”stated Timothy P. Clackson, Ph.D., president of research and development and chief scientific officer at ARIAD. "We believe that this is in the best interests of patient safety and the overall development of Iclusig.” Patients in the EPIC trial are being removed from treatment and will be transferred to the care of their physician. ARIAD announced in early September that fifty percent of patients, or approximately 264 patients, had been enrolled in the EPIC trial by that time. Final enrollment is 307 patients. The EPIC trial was a randomized, two-arm, multicenter trial that sought to compare the efficacy of ponatinib with that of imatinib in adult patients with newly diagnosed CML in the chronic phase. The trial was being conducted at approximately 150 investigational sites in more than 20 countries. Patients in the trial had to be at least 18 years of age and diagnosed with CML within six months prior to enrollment. Approximately 500 patients were to be randomized 1:1 to the standard dose of ponatinib (45 mg given orally once daily) or imatinib (400 mg given orally once daily). Increasing the imatinib dose to 600 mg or 800 mg per day was permitted. The primary endpoint of the trial was major molecular response at 12 months of treatment. Iclusig is commercially available in the U.S. and EU for patients with resistant or intolerant CML and Philadelphia-chromosome positive acute lymphoblastic leukemia. ARIAD continues to work with health authorities to make appropriate changes to the Iclusig product labeling to reflect the recently announced safety findings from the pivotal PACE trial that was the basis of its marketing approvals. Investor and analyst briefing and webcast ARIAD management will host a conference call and webcast to discuss these actions today, October 18 at 8:30 a.m. ET. The live webcast can be accessed by visiting the investor relations section of the Company's website at http://investor.ariad.com. The call can be accessed by dialing 866-318-8620 (U.S.) or +1 617-399-5139 (international) and providing the participant code 13718093. A replay of the call will be available on the ARIAD website approximately two hours after completion of the call and will be archived for three weeks.