 ImmunoGen Inc NASDAQ: IMGN shares have gained more than 30 during premarket trading in reaction to positive topline data from the SORAYA trial of mirvetuximab soravtansine for ovarian cancer. The trial is evaluating mirvetuximab as monotherapy in patients with folate receptor alpha FRα-high platinum-resistant ovarian cancer who have been previously treated with Roche Holdings AGs OTC: RHHBY Avastin bevacizumab. 