Keytruda and Padcev make early bladder cancer bid

Keytruda plus Padcev, already a standard of care in first-line metastatic bladder cancer, could soon go earlier, with the perioperative Keynote-905 (EV-303) trial toplined positive on Tuesday. The combo, given before and after surgery in cisplatin-ineligible muscle-invasive bladder cancer, spurred “clinically meaningful and statistically significant” improvements in event-free and overall survival versus surgery alone at its first interim efficacy analysis, according to Merck & Co, Pfizer and Astellas. The partners said they would discuss the results with regulators, but didn’t give timings for any filings. The data will be presented at an upcoming medical meeting. The study is also secondarily testing perioperative Keytruda, versus surgery alone, with evaluation continuing. Meanwhile, another phase 3 trial of the combo, Keynote-B15 or EV-304, sees the groups targeting cisplatin-eligible MIBC; data are expected by March 2026, Astellas has said. Merck is also testing Keytruda plus chemo in cisplatin-eligible disease, in Keynote-866. MIBC makes up around 30% of bladder cancer cases, and up to half are cisplatin-ineligible, the partners noted. However, the bigger pre-metastatic use is non-muscle invasive bladder cancer (NMIBC), an increasingly crowded field in which Keytruda monotherapy is already approved, but where intravesical Padcev recently slipped up in phase 1.

Notable Keytruda trials in bladder cancer

Note: *investigator-sponsored study. Source: OncologyPipeline & clinicaltrials.gov.