ARIAD Announces Result of First Interim Analysis of Phase 3 Succeed Trial of Oral Ridaforolimus, Its Investigational mTOR Inhibitor, in Metastatic Sarcomas

ARIAD Pharmaceuticals, Inc. (NASDAQ:ARIA) today announced that the independent Data Monitoring Committee (DMC) of the Phase 3 SUCCEED trial has completed the first interim efficacy analysis as specified by the study protocol and has recommended that the randomized, placebo-controlled trial of oral ridaforolimus in patients with metastatic sarcomas continue to full patient enrollment and completion. The DMC made this recommendation after reviewing the pre-specified statistical analyses and available data on the safety and efficacy of oral ridaforolimus.

The DMC review comprised approximately one-third of the total number of progression-free survival events anticipated in the trial. The safety and efficacy of oral ridaforolimus is being evaluated in patients with metastatic soft-tissue and bone sarcomas who have achieved a favorable response to chemotherapy. The primary end-point of the trial is progression-free survival.

The DMC indicated that the safety data from the first interim analysis are consistent with the known safety profile of ridaforolimus and that no modifications to the study protocol are recommended. Over 500 patients with metastatic soft-tissue and bone sarcomas have been enrolled in the trial to date. Full patient enrollment is expected to take place by year-end 2009, and the second interim analysis based on approximately two-thirds of the total number of progression-free survival events is expected by the end of the first quarter of 2010, as previously announced.

"The recommendation by the DMC to continue the Phase 3 SUCCEED trial to completion represents an important step in the development of oral ridaforolimus as a potential new treatment option for patients with metastatic sarcomas,” stated Harvey J. Berger, M.D., chairman and chief executive officer of ARIAD.

ARIAD and its partner, Merck & Co., Inc., have a global collaboration to jointly develop and commercialize ridaforolimus in oncology.

About the Independent DMC

The DMC is an independent, multi-disciplinary group consisting of medical oncologists and a biostatistician, who collectively have extensive experience in the management of patients with sarcomas and in the conduct and oversight of complex global trials. The DMC advises the sponsor regarding the continuing safety of trial subjects and those yet to be recruited to the trial, as well as the continuing validity and scientific merit of the trial. According to the study protocol, the DMC is responsible for undertaking the two interim efficacy analyses.

About the SUCCEED Trial Design and Special Protocol Assessment

The SUCCEED (Sarcoma Multi-Center Clinical Evaluation of the Efficacy of Ridaforolimus) trial is a randomized, double-blind, placebo-controlled Phase 3 study of oral ridaforolimus in patients with metastatic sarcoma who have achieved a favorable response to chemotherapy. Continued treatment with traditional chemotherapeutic drugs has not been established to provide additional clinical benefit after such a response. Absent new alternatives, physicians generally would either continue chemotherapy until the side effects become unacceptable or, more commonly, monitor patients carefully for disease progression (tumor growth) prior to initiating another line of chemotherapy. Therefore, the placebo arm represents the current standard of care for most patients in this clinical setting.

This trial is designed to assess approximately 650 patients who are randomized (1:1) to oral ridaforolimus or placebo at approximately 125 sites. The trial is 90 percent powered to detect a 33 percent increase in median progression-free survival (corresponding to a hazard ratio of 0.75) comparing the ridaforolimus arm with the placebo arm.

ARIAD has a Special Protocol Assessment (SPA) with the U.S. Food and Drug Administration for the SUCCEED trial. The European Medicines Agency has provided protocol advice regarding the trial design as part of its Protocol Assistance program.

About Sarcoma

Sarcomas are a group of aggressive cancers of connective tissue of the body for which there are currently limited treatment options. Sarcomas can arise anywhere in the body and are divided into two main groups – bone tumors and soft-tissue sarcomas. They are further subdivided based on the type of cell or tissue which the tumor resembles. In 2009, the American Cancer Society estimates that approximately 10,600 new cases of soft-tissue sarcomas will be diagnosed in the United States, and more than 3,800 Americans will die of the disease. In addition, approximately 2,600 new cases of bone sarcomas will be diagnosed and nearly 1,500 deaths are estimated. There has been no new approved therapy in the U.S. for patients with soft-tissue or bone sarcomas in more than 25 years.

About Ridaforolimus

Ridaforolimus (formerly known as deforolimus) is a novel small-molecule inhibitor of the protein mTOR, a "master switch” in cancer cells. Blocking mTOR creates a starvation-like effect in cancer cells by interfering with cell growth, division, metabolism and angiogenesis. ARIAD is collaborating with Merck & Co., Inc. to globally develop and commercialize ridaforolimus. In addition to the SUCCEED trial, multiple Phase 2 and Phase 1 clinical trials of ridaforolimus, both alone and in combination with targeted therapies, are ongoing.

Ridaforolimus has been designated both as a fast-track and orphan drug product by the U.S. Food and Drug Administration (FDA) and as an orphan drug by the European Medicines Agency (EMEA) for the treatment of soft-tissue and bone sarcomas. ARIAD and Merck are pursuing this indication as the initial registration path for ridaforolimus.

About ARIAD

ARIAD’s vision is to transform the lives of cancer patients with breakthrough medicines. The Company’s mission is to discover, develop and commercialize small-molecule drugs to treat cancer in patients with the greatest and most urgent unmet medical need – aggressive cancers where current therapies are inadequate. ARIAD’s lead product candidate, ridaforolimus, is an investigational mTOR inhibitor in Phase 3 clinical development in patients with advanced sarcomas and is being developed in collaboration with Merck & Co., Inc. ARIAD’s second product candidate, AP24534, is an investigational multi-targeted kinase inhibitor in Phase 1 clinical development in patients with hematological cancers. ARIAD has an exclusive license to pioneering technology and patents related to certain NF-?B cell-signaling activity, which may be useful in treating certain diseases. For additional information about the Company, please visit http://www.ariad.com.

This press release contains "forward-looking statements” including, but not limited to, statements relating to the implications of clinical findings and recommendations from interim data analyses, the timing of clinical trial patient enrollment and the interim analyses, and the potential clinical opportunities of ridaforolimus. Forward-looking statements are based on management's 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 statements. These risks and uncertainties include, but are not limited to, clinical data that may not be replicated in later-stage clinical studies, the costs associated with our research, development, manufacturing and other activities, the conduct, timing and results of pre-clinical and clinical studies of our product candidates, the adequacy of our capital resources and the availability of additional funding, and other factors detailed in the Company's public filings with the U.S. Securities and Exchange Commission. The information contained in this press release 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.