A phase II study of ganetespib (G) as second- or third-line therapy for metastatic pancreatic cancer (MPC).

297 Background: Heat shock protein 90 (HSP90) regulates folding, stability and function of signaling proteins such as EGFR, IGF-1R, c-Met, ERBB4, PDGFRα and c-Ret, several of which are key pathways for MPC pathogenesis. G prevents Hsp90 binding to client proteins leading to inactivation and degradation, disrupting signaling that promotes cancer progression. This phase II study is designed to evaluate the efficacy of G in patients (pts) with refractory MPC. Methods: Pts with MPC in the 2nd or 3rd line setting, with PS 0-1, received G 175 mg/m2intravenously once weekly for 3 weeks out of a 4 week cycle. Primary endpoint was disease control rate (DCR) at 8 weeks, with a goal of 70% DCR. Secondary endpoints were response rate (RR), overall survival (OS), and safety. 43 pts were planned for initial accrual. Simon’s optimal two-stage design was used to assess 8 week DCR. G was considered inactive if 8 or fewer pts among the first 15 treated had disease control after 8 weeks of treatment (tx). Results: Seventeen...