ASCO 2026: RAD-IO Phase 2 — Adding Durvalumab to Chemoradiotherapy Achieves 84% Disease-Free Survival at 1 Year in Muscle-Invasive Bladder Cancer, Avoiding Surgery

Phase 2 RAD-IO trial data, presented at ASCO 2026 in collaboration between Cancer Research UK and academic oncology centers, demonstrated that adding durvalumab (anti-PD-L1; AstraZeneca) to standard chemoradiotherapy (5-fluorouracil + mitomycin C + 55 Gy in 20 fractions) achieved a 12-month disease-free survival rate of 84% in 54 patients with muscle-invasive bladder cancer (MIBC) — a rate substantially higher than the approximately 60% seen historically with chemoradiation alone (BC2001 trial). The 12-month overall survival rate was 96.4%. Crucially, the cystectomy (bladder removal) rate at 1 year was 0%: all patients maintained their bladder on the surgery-sparing strategy. A total of 87% of patients completed treatment without delays, indicating the addition of durvalumab was well-tolerated. Muscle-invasive bladder cancer requires radical cystectomy as the gold-standard curative treatment, but the procedure carries substantial morbidity including lifelong urinary diversion. Bladder-sparing trimodality therapy (chemoradiation) has long been offered as an alternative for selected patients, but recurrence rates remain significant. Adding immunotherapy to chemoradiation represents a strategy to improve the bladder-sparing option to parity or better versus surgery. A larger randomized trial is planned based on RAD-IO data. These results complement the May 2026 FDA approval of atezolizumab + ctDNA biomarker guidance for adjuvant bladder cancer (IMvigor011), establishing immunotherapy as increasingly central to bladder cancer management across disease stages.