Verastem Drug Achieves a Complete Response in Platinum-Resistant Ovarian Cancer

Verastem, Inc.

, focused on discovering and developing drugs to treat cancer by the targeted killing of cancer stem cells, today announced the confirmation of a complete response in an ongoing trial of VS-6063 (defactinib) in combination with weekly paclitaxel. At Verastem's Research and Development Day on July 11th, Dr. Horobin, Chief Medical Officer, presented preliminary results describing a normalization of CA-125, a biomarker of ovarian cancer progression, and an initial radiologic complete response for one of the patients in the trial. Response Evaluation Criteria in Solid Tumors, or RECIST, is the standard by which investigational drugs are evaluated for activity in oncology studies. “We have now confirmed the previously reported complete response by RECIST criteria with a second radiographic scan at the end of cycle four,” said Dr. Joanna Horobin. “The CA-125 level in this subject with platinum-resistant ovarian cancer normalized after the first cycle of treatment and has remained at normal levels since. We are encouraged by this early result and will continue to follow all patients in this study closely. We plan to report an update on the results of this study at scientific conferences later this year.” The Phase 1 dose escalation portion of the study in six patients treated at the Sarah Cannon Research Institute was well tolerated at all dose levels with no exacerbation of the well-known adverse effects of paclitaxel. In a randomized, placebo controlled study presented by McNeish et. al. at the 2013 ASCO annual conference, only 1 complete response was reported in a total of 107 patients with platinum-resistant ovarian cancer treated with weekly paclitaxel alone or weekly paclitaxel plus study drug. Verastem recently initiated the expansion Phase 1b stage of the study and expects to enroll an additional 15 patients with ovarian cancer at three U.S. locations. The Phase 1b trial is an open-label, multicenter, trial of defactinib in combination with paclitaxel. The endpoints of the study are safety, tolerability and efficacy as determined by Response Evaluation Criteria in Solid Tumors (RECIST) and proprietary cancer stem cell biomarkers. About Verastem, Inc. Verastem, Inc.

is discovering and developing drugs to treat cancer by the targeted killing of cancer stem cells. Cancer stem cells are an underlying cause of tumor recurrence and metastasis. Verastem is developing small molecule inhibitors of signaling pathways that are critical to cancer stem cell survival and proliferation: FAK, PI3K/mTOR and Wnt. For more information, please visit www.verastem.com.