Merck secures CHMP positive opinion for KEYTRUDA + Padcev in cisplatin‑ineligible resectable MIBC

Key highlights
  • CHMP adopted a positive opinion recommending pembrolizumab plus enfortumab vedotin‑ejfv as perioperative (neoadjuvant then adjuvant) treatment for cisplatin‑ineligible resectable MIBC; EC decision expected by Q3 2026.
  • Phase 3 KEYNOTE‑905 showed a 60% reduction in EFS events (HR=0.40; p<0.0001), 50% reduction in risk of death (OS HR=0.50; p=0.0002) and pCR 57.1% vs 8.6% versus surgery alone.
  • Median EFS was not reached with the combination versus 15.7 months for surgery alone, and median OS was not reached versus 41.7 months for surgery alone.
  • The trial (EV‑303/KEYNOTE‑905) was conducted with Pfizer and Astellas, and the FDA approved KEYTRUDA (and KEYTRUDA QLEX) plus Padcev in November 2025.

Regulatory update

CHMP issued a positive opinion recommending pembrolizumab plus enfortumab vedotin‑ejfv as neoadjuvant treatment continued as adjuvant therapy for adults with cisplatin‑ineligible resectable muscle‑invasive bladder cancer; the opinion will be reviewed by the European Commission with a decision expected by Q3 2026.

Key clinical results

Phase 3 KEYNOTE‑905 (EV‑303), conducted with Pfizer and Astellas, reported a 60% reduction in risk of EFS events (HR 0.40; p<0.0001), 50% reduction in risk of death (OS HR 0.50; p=0.0002), median EFS not reached versus 15.7 months (surgery alone), median OS not reached versus 41.7 months, and pathologic complete response 57.1% vs 8.6% (p<0.0001).

Clinical context

Neoadjuvant cisplatin‑based chemotherapy followed by surgery is standard for MIBC, but up to half of patients are cisplatin‑ineligible and often undergo surgery alone; in Europe an estimated 224,700 bladder cancer diagnoses and over 70,300 deaths occurred in 2022, with about 25% of new cases classified as MIBC.

Regulatory precedent

In November 2025 the U.S. FDA approved pembrolizumab (including subcutaneous KEYTRUDA QLEX) in combination with enfortumab vedotin‑ejfv as perioperative treatment for the same cisplatin‑ineligible MIBC population.