US pharmaceutical company Merck & Co Inc (NYSE:MRK), known as MSD outside the US and Canada, announced on Wednesday that the European Commission has approved KEYTRUDA (pembrolizumab) for the treatment of adults with resectable locally advanced head and neck squamous cell carcinoma (LA-HNSCC) whose tumours express PD-L1 with a Combined Positive Score (CPS) ≥1.

The approval covers use as neoadjuvant monotherapy, followed by adjuvant treatment with radiotherapy (with or without cisplatin) and continued as monotherapy.

This marks the first and only anti-PD-1 treatment option authorised in the European Union for resectable LA-HNSCC and represents KEYTRUDA's third EU approval in head and neck cancer. The decision is based on data from the Phase 3 KEYNOTE-689 trial, which demonstrated a 30% reduction in the risk of disease recurrence, progression, or death compared with standard adjuvant radiotherapy, with or without cisplatin.

Patients in the KEYTRUDA arm achieved a median event-free survival of 59.7 months versus 29.6 months in the control group. The approval applies to all 27 EU member states, as well as Iceland, Liechtenstein, and Norway, with commercial availability subject to national reimbursement processes.

KEYTRUDA received similar approvals earlier in 2025 in the United States, Canada, Brazil, Switzerland, and other markets based on the same trial results.