Merck (NYSE:MRK) announced positive topline results from the Phase 3 KEYNOTE-B15 trial (also known as EV-304) in patients with muscle-invasive bladder cancer (MIBC) who are eligible for cisplatin-based chemotherapy.
The trial demonstrated that the combination of KEYTRUDA® (pembrolizumab) and Padcev® (enfortumab vedotin-ejfv), when administered as neoadjuvant and adjuvant treatment, significantly improved event-free survival (EFS), overall survival (OS), and pathologic complete response (pCR) rates compared to standard chemotherapy and surgery.
Dr. Matthew Galsky, principal study investigator and director of genitourinary medical oncology at Mount Sinai Tisch Cancer Center, highlighted the trial's importance, stating that the results could potentially change the treatment landscape for MIBC, as many patients still experience recurrence despite existing therapies.
The trial was conducted in collaboration with Pfizer and Astellas and builds on the successful application of this combination in metastatic urothelial cancer (la/mUC) and cisplatin-ineligible MIBC.
The data suggests that administering pembrolizumab plus enfortumab vedotin earlier in the treatment cycle could significantly improve survival outcomes in patients with MIBC.
Currently, the combination of KEYTRUDA and Padcev is approved for treating adult patients with la/mUC in multiple regions, including the U.S., EU, and Japan, and for treating MIBC patients ineligible for cisplatin-based chemotherapy in the U.S.
Merck is also advancing multiple Phase 3 trials for KEYTRUDA in various stages of bladder cancer, including non-muscle-invasive, muscle-invasive, and metastatic settings