Perioperative pembrolizumab therapy in muscle-invasive bladder cancer: Phase III KEYNOTE-866 and KEYNOTE-905/EV-303.

Muscle-invasive bladder cancer (MIBC) is associated with high rates of recurrence and poor prognosis despite aggressive treatment. Neoadjuvant chemotherapy before radical cystectomy (RC) improves outcomes in cisplatin-eligible patients; however, the improvement in overall survival is modest. Standard of care for cisplatin-ineligible patients remains RC; more effective systemic therapies are needed. Recent Phase Ib/II studies suggest pembrolizumab monotherapy and combination therapy are effective neoadjuvant therapies for MIBC. The randomized Phase III KEYNOTE-866 and KEYNOTE-905/EV-303 studies are being conducted to evaluate efficacy and safety of perioperative pembrolizumab or placebo with chemotherapy in cisplatin-eligible patients with MIBC (KEYNOTE-866) and of pembrolizumab monotherapy versus pembrolizumab plus enfortumab vedotin versus RC plus pelvic lymph node dissection alone in cisplatin-ineligible patients with MIBC (KEYNOTE-905/EV-303). Clinical trial registration: NCT03924856 & NCT03924895 (ClinicalTrials.gov).