Merck & Co. Inc. (MRK) delivered positive news Wednesday from its Phase 3 KEYNOTE-B15 trial (also called EV-304), showing that its blockbuster immunotherapy Keytruda combined with Padcev worked significantly better than chemotherapy in treating muscle-invasive bladder cancer.
The study focused on patients with muscle-invasive bladder cancer who are eligible for cisplatin-based chemotherapy. When given before and after surgery (what doctors call neoadjuvant and adjuvant treatment), the Keytruda-Padcev combo delivered statistically significant and clinically meaningful improvements across the board. We're talking better event-free survival, better overall survival, and higher rates of pathologic complete response compared to the standard approach of neoadjuvant chemotherapy followed by surgery.
Merck conducted the trial in collaboration with Pfizer Inc (PFE) and Astellas Pharma Inc (ALPMF) (ALPMY). Padcev (enfortumab vedotin-ejfv) is jointly developed by the three companies, while Keytruda (pembrolizumab) is Merck's heavyweight immunotherapy that's already approved for multiple cancer types.
On the safety front, the combination behaved as expected. The safety profile matched what researchers already know about each drug individually, with no unexpected side effects showing up when they're used together.
Merck plans to take these results to regulatory authorities worldwide for potential approval filings and will present the full data at an upcoming medical conference where we'll get more granular details about exactly how much benefit patients saw.
This trial is just one piece of Merck's broader bladder cancer strategy. The company is currently running three additional Phase 3 studies testing Keytruda across the full spectrum of bladder cancer stages. Two of those studies (KEYNOTE-866 and KEYNOTE-992) focus on muscle-invasive disease, while KEYNOTE-676 is evaluating Keytruda combined with BCG (Bacillus Calmette-Guerin) in patients with non-muscle-invasive bladder cancer.
MRK Price Action: Merck stock was up 0.37% at $98.63 at publication Wednesday.