Ridaforolimus is a novel small-molecule inhibitor of the protein mTOR that acts as a central regulator of protein synthesis, cell proliferation, cell cycle progression and cell survival in cancer cells. Blocking mTOR creates a starvation-like effect in cancer cells by interfering with cell growth, division, metabolism and angiogenesis.
In addition, ridaforolimus is being studied in Phase 2 clinical trials in advanced endometrial cancer, prostate cancer and non-small cell lung cancer, as well as in combination with various biological agents in other trials. A Phase 2 registration trial of ridaforolimus in patients with metastatic soft-tissue or bone sarcomas is ongoing in Japan.
Ridaforolimus is currently being evaluated in the Phase 3 SUCCEED trial in patients with metastatic soft-tissue and bone sarcomas who have had a favorable response to chemotherapy. This trial is fully enrolled, and clinical results are expected in late 2010.
ARIAD and Merck entered into a collaboration for ridaforolimus in July 2007 and worked together to develop ridaforolimus in multiple potential cancer indications. In May 2010, both companies announced the restructuring of the partnership. Under this new collaboration framework, ARIAD granted Merck an exclusive license to develop, manufacture and commercialize ridaforolimus in oncology, and Merck has assumed responsibility for ridaforolimus activities, including clinical trials and regulatory filings. For more information about the ARIAD-Merck collaboration, please see Our Collaboration with Merck.

