RAHWAY, N.J. — Merck (NYSE: MRK), known as MSD outside the United States and Canada, announced that the U.S. Food and Drug Administration (FDA) has granted priority review for two supplemental Biologics License Applications (sBLAs) for KEYTRUDA (pembrolizumab) and KEYTRUDA QLEX (pembrolizumab and berahyaluronidase alfa-pmph), each in combination with Padcev (enfortumab vedotin-ejfv), for the treatment of patients with muscle-invasive bladder cancer (MIBC) who are ineligible for cisplatin-based chemotherapy. The FDA has set April 7, 2026, as the target action date under the Prescription Drug User Fee Act (PDUFA), marking the first concurrent review of both KEYTRUDA and KEYTRUDA QLEX for the same indication.
“New options for muscle-invasive bladder cancer are vital — patients who are ineligible for chemotherapy have not seen a treatment advance beyond surgery in decades,” said Dr. Marjorie Green, senior vice president and head of oncology, global clinical development, Merck Research Laboratories. “With the FDA’s priority review, we are one step closer to offering KEYTRUDA or KEYTRUDA QLEX plus Padcev as a potential treatment option to these patients with MIBC who are ineligible for cisplatin-containing chemotherapy and have such high unmet medical need.”
The sBLAs are supported by data from the Phase 3 KEYNOTE-905 trial (also known as EV-303), conducted in collaboration with Pfizer and Astellas. Results presented at the European Society for Medical Oncology (ESMO) Congress showed that after a median follow-up of 25.6 months, perioperative treatment with KEYTRUDA plus Padcev demonstrated a statistically significant and clinically meaningful improvement in event-free survival (EFS), the study’s primary endpoint. The regimen reduced the risk of EFS events by 60 percent (HR=0.40 [95% CI, 0.28–0.57]; p<0.0001) compared with surgery alone in patients with MIBC who were not eligible for or declined cisplatin-based chemotherapy. Median EFS was not reached (95% CI, 37.3–NR) for KEYTRUDA plus Padcev versus 15.7 months (95% CI, 10.3–20.5) for surgery alone.
KEYTRUDA plus Padcev also achieved statistically significant improvements in key secondary endpoints, including overall survival (OS) and pathologic complete response (pCR) rate. The combination reduced the risk of death by 50 percent (HR=0.50 [95% CI, 0.33–0.74]; p=0.0002) compared with surgery. The pCR rate increased from 8.6 percent in patients treated with surgery alone to 57.1 percent in those treated with KEYTRUDA plus Padcev, representing a 48.3 percentage-point increase (95% CI, 39.5–56.5; p<0.000001).
KEYTRUDA plus Padcev is currently approved for the treatment of adult patients with locally advanced or metastatic urothelial cancer (la/mUC) in the U.S., the European Union, Japan, and several other countries, based on results from the Phase 3 KEYNOTE-A39 (EV-302) trial. KEYTRUDA monotherapy is also approved in these markets for certain patients with la/mUC or non-muscle-invasive bladder cancer (NMIBC).
Four additional Phase 3 studies are evaluating KEYTRUDA across all stages of bladder cancer, including non-muscle-invasive, muscle-invasive, and metastatic disease. These include KEYNOTE-B15 (EV-304), conducted with Pfizer and Astellas; KEYNOTE-866; and KEYNOTE-992 in MIBC, as well as KEYNOTE-676, evaluating KEYTRUDA in combination with Bacillus Calmette-Guerin (BCG) in NMIBC.
