Ixabepilone

Ixabepilone (BMS 247550) is an epothilone B analog and nontaxane microtubule-stabilizing compound. Ixabepilone induces cell cycle arrest at the G(2)-M phase transition and subsequent apoptotic cell death of MDA-MB-468 (468) cells. Ixabepilone, on a once every 21-day schedule, is modestly active against metastatic gastric cancer previously treated with a taxane. The days 1-5 every 21 days schedule had a more favorable safety profile but no activity. The results of this study suggest that once every 21-day ixabepilone schedule should be pursued further in untreated gastric or gastroesophageal adenocarcinoma patients. Ixabepilone has demonstrated activity in patients with chemotherapy-naive metastatic HRPC. Major toxicities were neutropenia and neuropathy. Further testing to define its activity relative to standard therapy is warranted.