Verastem Oncology Announces Efficacy and Safety Data of Avutometinib and Defactinib in Recurrent Low-Grade Serous Ovarian Cancer (LGSOC) in Heavily Pretreated Patient Population

Verastem Oncology (Nasdaq: VSTM) (the “Company”), a biopharmaceutical company committed to advancing new medicines for patients with cancer, announced today results of the efficacy and safety of avutometinib and defactinib in recurrent low-grade serous ovarian cancer (LGSOC) following prior systemic therapy. The results of this planned subgroup analysis of Part A of the Phase 2 RAMP 201 (ENGOT-ov60/GOG-3052) trial were presented as a late-breaking abstract in an oral presentation during a plenary session at the Annual Global Meeting of the International Gynecologic Cancer Society (IGCS 2023) November 5-7, 2023, in Seoul, Korea.

“Patients with recurrent LGSOC currently have no medicines approved by the U.S. Food and Drug Administration and limited treatment options for their disease,” said Rachel Grisham, M.D., Section Head, Ovarian Cancer and Director, Westchester Gynecologic Medical Oncology at Memorial Sloan Kettering Cancer Center N.Y., and the lead U.S. investigator of RAMP 201. “The results from this analysis are encouraging as the combination of avutometinib and defactinib demonstrates robust efficacy in recurrent LGSOC irrespective of the number of prior therapies, and for most of which, response to previous therapy was poor.”

This planned subgroup analysis was performed to assess efficacy (confirmed objective response rate (ORR) via blinded independent central review per RECIST v1.1) and safety in prior lines of therapy (LoT) (1-3 LoT, ≥4 LoT). The analysis also evaluated efficacy in the context of best response to most recent prior treatment in the metastatic/recurrent setting.

In the combination arm, the observed ORRs were consistent across patients who received 1-3 (45.5%, 5/11, 95% CI 17-77) and ≥4 lines of therapy (44.4%, 8/18, 95% CI 22-69). Prior to enrollment in RAMP 201, only 2/23 (8.7%) patients responded to their last prior treatment in the metastatic/recurrent setting, whereas the combination of avutometinib and defactinib yielded an ORR of 43.5% (10/23) in this subgroup. The safety profiles of avutometinib and defactinib were similar in the less and more heavily pretreated subgroups and both analyses were consistent with previously reported safety data. The majority of treatment-emergent adverse events were mild to moderate.