October 27, 2008

Infinity Initiates Phase III Registration Study of Tumor Drug

Infinity Pharmaceuticals, a cancer drug discovery and development company, has initiated a Phase III registration trial of IPI-504, its lead inhibitor of heat shock protein 90, in patients with refractory gastrointestinal stromal tumors.

The Ring trial is a randomized, double-blind, placebo-controlled study evaluating approximately 200 patients with refractory gastrointestinal stromal tumors (GIST) in over 20 countries and 50 sites worldwide. Patients whose tumors have grown despite treatment with at least imatinib and sunitinib are eligible to enroll in the Ring trial and there is no limit to the number of prior therapies they may have received.

The primary endpoint of the study is progression free survival; secondary endpoints include disease control rate, time to progression, and overall survival. Patients will be randomized 2:1 to IPI-504 or placebo, with a cross-over to treatment with IPI-504 if progression occurs. Response is being evaluated by response evaluation criteria in solid tumors (RECIST). Imaging with computed tomography scans will be obtained at early time points to enable close monitoring of tumor activity.

Initiation of the Phase III trial of IPI-504 follows promising safety and activity data reported earlier in 2008 from a Phase I study in patients with refractory GIST and other soft tissue sarcomas. The trial is expected to be completed within approximately two years, positioning IPI-504 as the potential first-in-class Hsp90 inhibitor.

IPI-504 is also being evaluated in the Phase II portion of a Phase I/II trial in patients with advanced non-small cell lung cancer and a Phase Ib trial in combination with docetaxel in patients with solid tumors. Additional clinical studies of IPI-504 are anticipated to begin by early 2009.