Engene Holdings (ENGN) stock surged 53% premarket after its experimental therapy Detalimogene voraplasmid achieved a 62% complete response rate at six months in high-risk, BCG-unresponsive bladder cancer patients. The company plans to file for FDA approval in the second half of 2026, marking a major milestone in developing treatments for non-muscle invasive bladder cancer (NMIBC).