A Mayo Clinic–led international Phase 3 trial reported in The Lancet Oncology suggests an intravesical oncolytic immunotherapy, cretostimogene grenadenorepvec, may help some patients with high-risk, BCG-unresponsive non-muscle-invasive bladder cancer avoid immediate cystectomy. The study enrolled patients whose disease returned or persisted after Bacillus Calmette-Guérin (BCG), and evaluated whether the investigational approach could change treatment trajectories in a setting where options are limited and major surgery is common. If confirmed in secondary endpoints and longer follow-up, the results could alter how clinicians sequence intravesical therapies relative to surgical management for BCG-unresponsive disease. For the urology oncology market, the readout provides a potential new mechanism—oncolytic immunotherapy delivered directly into the bladder—that aims to improve local control without defaulting to radical removal.