A Mayo Clinic-led international Phase 3 trial reported that cretostimogene grenadenorepvec, an intravesical oncolytic immunotherapy, may help some patients with high-risk, BCG-unresponsive non-muscle-invasive bladder cancer avoid immediate cystectomy. The study, published in The Lancet Oncology, evaluated outcomes in patients whose disease returned or persisted after Bacillus Calmette-Guérin, the standard frontline therapy for this setting. If confirmed in regulatory discussions, the trial would reinforce an immunotherapy pathway designed to preserve the bladder while improving disease control in a population with limited options.