BUZZ-Verastem gains on positive ovarian cancer drug results

** Verastem VSTM.O shares rose 1.8% to $3.31 premarket

** Cancer drugmaker says treatments avutometinib plus defactinib show an 18% response rate in patients with recurrent low-grade serous ovarian cancer whose tumors lack three key mutations

** Says patients went a median 13 months without disease worsening

** Adds that drug combination shows stronger results than conventional care

** Safety risks include eye problems, serious skin reactions, liver damage and muscle injury; requires regular monitoring - VSTM

** Results to be presented at IGCS 2026 meeting, Montreal on Friday

** As of last close, VSTM up 2.33% YTD

(Reporting by Jayasree Prabhu)