Abstract

5085 Background: Hsp90 is a molecular chaperone required for the proper folding and activation of numerous client proteins and is critical to cell survival and proliferation. Ganetespib (G), a synthetic small molecule that binds to the ATP pocket in the N-terminus of Hsp90 causes the degradation of cellular proteins and ultimately death of cancer cells dependent on these proteins. G displays potent anticancer activity in prostate cancer cells. Methods: Eligible patients were ≥ 18 yrs old with ECOG performance status ≤ 2. Adequate hepatic, renal, and bone marrow function was required. Patients were treated with G 200 mg/m2 intravenously once weekly for 3 consecutive weeks followed by 1 off-week. The primary objective was to evaluate the 6-month progression-free survival (PFS). Secondary endpoints included overall safety and tolerability of G and overall survival. Exploratory markers including maspin, cytokeratins 8 and 18, and HDAC1 were obtained pre, during, and post G treatment. We sought ≥ 4 patients with ≥ 6 months PFS (a success) in Stage 1 of a 2-stage near-optimal Simon design. Results: 18 patients were enrolled at 4 institutions. The patients’ median age was 68 (range 51-82), 13 were Caucasian, 4 were African American, and 1 was Asian. Median PSA was 210.7 ng/mL (range 25.9 – 3,489 ng/mL). One patient never started therapy. Among the 17 treated patients, the median number of cycles was 2 (range 1-5). The most frequent Grade 3 toxicities were diarrhea (3 patients), fatigue (3), and dehydration (3). Prior therapy included abiraterone (8), sipuleucel-T (4), and other targeted therapy (4). With < 4 successes in Stage 1, the trial was terminated early. Median PFS was 1.9 months (90% CI: 1.7 – 2.7 months); median OS was 10.2 months (90% CI: 2.3 – 18.3 months). Exploratory markers have been evaluated and will be presented. Conclusions: Our study represents the first clinical trial of G in treating mCRPC patients. As a single agent therapy, G did not prolong PFS. Combination therapy is a consideration to improve therapeutic efficacy. Clinical trial information: NCT01270880.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.