Kenilworth, N.J., October 29, 2025— Merck & Co., Inc. (NYSE: MRK), known as MSD outside the U.S. and Canada, today announced that the European Commission (EC) has approved KEYTRUDA® (pembrolizumab) as part of a peri-operative treatment regimen for adults with resectable, locally advanced head and neck squamous cell carcinoma (LA-HNSCC) whose tumors express PD-L1 (Combined Positive Score ≥ 1). This marks the first anti-PD-1 immunotherapy approved for peri-operative use in this cancer type, expanding the reach of KEYTRUDA into earlier, potentially curative stages of disease.
Science Significance
Head and neck squamous cell carcinoma remains one of the most challenging malignancies, with high recurrence rates despite surgery and adjuvant therapy. The approval was supported by results from the Phase 3 KEYNOTE-689 trial, which evaluated pembrolizumab in combination with surgery and radiotherapy (with or without cisplatin).
In patients with PD-L1 CPS ≥ 1 tumors, the regimen significantly reduced the risk of event-free survival (EFS) events by 30% (HR = 0.70; 95% CI 0.55-0.89; p = 0.0014) compared with standard of care alone. Median EFS more than doubled — 59.7 months vs 29.6 months in the control arm. By integrating checkpoint inhibition both before and after surgery, KEYTRUDA introduces an entirely new therapeutic paradigm: mobilizing the immune system early to eliminate micrometastatic disease and prevent relapse. This represents a major scientific leap for immuno-oncology — moving from palliative to curative-intent applications.
Regulatory Significance
The European Commission’s decision follows a positive recommendation from the Committee for Medicinal Products for Human Use (CHMP) and applies to all 27 EU Member States, as well as Iceland, Liechtenstein, and Norway.
It is the first EU approval for an anti-PD-1 therapy in the peri-operative setting for resectable LA-HNSCC, reflecting a new level of confidence in immune-checkpoint blockade for earlier-stage disease. This approval mirrors the U.S. Food and Drug Administration’s (FDA) earlier authorization in June 2025 for the same indication, underscoring global regulatory alignment in recognizing the value of peri-operative immunotherapy. By anchoring pembrolizumab within standard surgical oncology pathways, the decision sets a new benchmark for biomarker-driven treatment strategies and opens the door for future filings across multiple early-stage tumor types.
Business Significance
Advertisement
For Merck, this milestone strengthens its leadership in oncology and broadens the commercial life cycle of KEYTRUDA, already approved in over 30 cancer indications. Expanding into earlier-stage disease translates to longer treatment duration and larger eligible patient populations — a critical factor as the company prepares for KEYTRUDA’s eventual patent expiry later this decade. The peri-operative indication adds strategic depth to Merck’s immunotherapy portfolio and enhances differentiation in a competitive market where rivals are pursuing similar early-disease opportunities. Industry analysts estimate that peri-operative and adjuvant uses of immunotherapy could add several billion dollars in incremental annual revenue by 2030, particularly in cancers with strong PD-L1 biomarker expression. In parallel, Merck continues to invest heavily in novel combinations, bispecific antibodies, and next-generation checkpoint inhibitors, leveraging real-world evidence and digital pathology to sustain its innovation edge.
Patients’ Significance
For patients with resectable LA-HNSCC, this approval represents a new era of hope. Historically, recurrence rates have remained high even after aggressive multimodal therapy, often resulting in devastating outcomes for speech, swallowing, and quality of life. By introducing immunotherapy before surgery, KEYTRUDA gives clinicians an opportunity to reduce tumor burden early, improve resectability, and potentially eradicate residual microscopic disease post-operation. “This decision changes the trajectory of how we treat high-risk head and neck cancer,” said Dr. Vicki Goodman, head of global oncology clinical development at Merck. “By leveraging the body’s immune system across the surgical journey, we may now help patients achieve longer disease-free survival and more durable outcomes.” For thousands of European patients each year, the availability of pembrolizumab in this setting could redefine long-term survival prospects and bring curative intent within reach for many who previously faced limited options.
Policy Significance
From a health-policy perspective, the EC’s approval reflects the ongoing shift toward earlier intervention, precision oncology, and biomarker-guided care. It will likely prompt updates to European treatment guidelines, including the integration of PD-L1 testing as standard practice in resectable head and neck cancer. National reimbursement authorities across the EU will now evaluate coverage frameworks for peri-operative immunotherapy — a key step to ensure equitable access. The decision also aligns with the European Beating Cancer Plan, which prioritizes innovation, prevention, and early treatment as pillars for reducing cancer mortality. By supporting evidence-based adoption of immunotherapy in curative settings, the EC signals a strong policy commitment to accelerating transformative oncology advances while maintaining patient safety and cost transparency.
Transaction Highlights
Merck’s KEYTRUDA (pembrolizumab) has received European Commission approval for use as part of a peri-operative treatment regimen in adults with resectable, locally advanced head and neck squamous cell carcinoma expressing PD-L1 (CPS ≥ 1). The approved regimen involves neoadjuvant KEYTRUDA monotherapy, followed by surgery, then adjuvant KEYTRUDA combined with radiotherapy (with or without cisplatin) and maintenance KEYTRUDA monotherapy. The approval is based on data from the Phase 3 KEYNOTE-689 trial, which demonstrated a 30% reduction in risk of disease recurrence, progression, or death, with median EFS improving from 29.6 to 59.7 months compared to standard therapy. This decision reinforces Merck’s scientific leadership in immuno-oncology and provides a new, clinically validated option for earlier intervention in
LA-HNSCC, complementing prior metastatic indications.
Source: Merck & Co., Inc. Press Release
