FDA Grants Priority Review to Supplemental Biologics License Application (sBLA) for KEYTRUDA Plus Chemotherapy for the Treatment of Certain Patients With Metastatic TNBC Based on KEYNOTE-355 Trial
FDA Accepts sBLA for KEYTRUDA for the Treatment of Patients with High-Risk Early-Stage TNBC Based on KEYNOTE-522 Trial
Merck (NYSE:MRK), known as MSD outside the United States and Canada, today announced that the U.S. Food and Drug Administration (FDA) has accepted two new supplemental Biologics License Applications (sBLAs) for KEYTRUDA, Merck's anti-PD-1 therapy. The FDA has accepted and granted priority review for a new sBLA seeking accelerated approval for KEYTRUDA in combination with chemotherapy for the treatment of patients with locally recurrent unresectable or metastatic triple-negative breast cancer (TNBC) whose tumors express PD-L1 (Combined Positive Score [CPS] ≥10), based on the Phase 3 KEYNOTE-355 trial. The FDA has set a Prescription Drug User Fee Act (PDUFA), or target action, date of Nov. 28, 2020. The FDA also accepted for standard review a new sBLA for KEYTRUDA for the treatment of patients with high-risk early-stage TNBC, in combination with chemotherapy as neoadjuvant treatment, and then as a single agent as adjuvant treatment after surgery, based on the Phase 3 KEYNOTE-522 trial. The PDUFA date for this application is March 29, 2021.
"There is a real need to advance new treatment options for triple-negative breast cancer, an aggressive form of the disease. The FDA's acceptance of these KEYTRUDA applications for review is an important step toward helping patients with both early-stage and metastatic disease," said Dr. Roy Baynes, senior vice president and head of global clinical development, chief medical officer, Merck Research Laboratories. "These acceptances mark the first U.S. applications for KEYTRUDA in breast cancer, and we look forward to working closely with the FDA to bring these new options to patients as quickly as possible."
The applications are based on data from the KEYNOTE-355 and KEYNOTE-522 trials, respectively. In KEYNOTE-355, KEYTRUDA plus chemotherapy demonstrated a statistically significant and clinically meaningful improvement in progression-free survival (PFS) compared with chemotherapy alone in patients whose tumors expressed PD-L1 at CPS ≥10. Approximately 38% of patients enrolled in KEYNOTE-355 had tumors expressing PD-L1 at CPS ≥10. These data were presented at the virtual scientific program of the 2020 American Society of Clinical Oncology (ASCO) Annual Meeting. As previously announced, the trial will continue without changes to evaluate the other dual primary endpoint of overall survival (OS).
In KEYNOTE-522 – the first randomized trial of an anti-PD-1 therapy in the neoadjuvant/adjuvant setting for TNBC – neoadjuvant KEYTRUDA plus chemotherapy resulted in a statistically significant increase in pathologic complete response (pCR) in patients with early-stage TNBC, regardless of PD-L1 expression. The KEYTRUDA regimen also demonstrated a favorable trend for the other dual primary endpoint of event-free survival (EFS). Data from the KEYNOTE-522 trial were presented at the European Society for Medical Oncology (ESMO) 2019 Congress and the 2019 San Antonio Breast Cancer Symposium (SABCS). As previously announced, KEYTRUDA plus chemotherapy was granted Breakthrough Therapy designation by the FDA for the neoadjuvant treatment of patients with high-risk early-stage TNBC.