IPI-504, Infinity's lead oncology drug candidate, is a small molecule inhibitor of Heat Shock Protein 90 (Hsp90) that is being jointly developed by Infinity and MedImmune for the treatment of Gleevec-resistant metastatic gastrointestinal stromal tumors (GIST).
IPI-504 has been well tolerated to date at all dose levels tested, although a maximum tolerated dose has not yet been identified. Patients included in the study were heavily pre-treated and nearly all had failed prior therapy with Sutent as well as Gleevec, two approved therapies for the treatment of GIST.
“We are very encouraged by the data emerging from this phase I clinical trial of IPI-504 in patients with treatment-refractory progressive GIST, which is reminiscent of the clinical data seen with other approved therapies such as the kinase inhibitors Gleevec and Sutent,” said Dr George Demetri, director of the Ludwig Center at Dana-Farber Cancer Institute. “Kinase inhibitors have been dramatically effective but over time we have seen tumors become resistant to these therapies. IPI-504 has an important new mechanism of action with the potential to benefit patients even with resistant disease.”
Based on this preliminary data, Infinity and MedImmune are expanding this phase I trial to add a second schedule of administration.