By Fineline Cube 
At the European Society for Medical Oncology (ESMO) 2025 Congress, Eisai (TYO: 4523) and Merck, Sharp & Dohme Inc. (MSD; NYSE: MRK) unveiled compelling long‑term follow‑up data from the Phase III 309/KEYNOTE‑775 trial. The combination of Eisai’s oral multitargeted tyrosine‑kinase inhibitor lenvatinib and MSD’s anti‑PD‑1 antibody Pembrolizumab (Keytruda) demonstrated sustained overall survival (OS) benefits over conventional chemotherapy in patients with advanced endometrial carcinoma who had progressed after at least one platinum‑based regimen.
Key Findings
| Population | 5‑Year OS (Len‑Pemb) | 5‑Year OS (Chemo) |
|---|---|---|
| All‑study cohort | 16.7 % | 7.3 % |
| Mismatch‑repair proficient (pMMR) | 19.9 % | 7.7 % |
- Consistent Benefit – The pMMR subgroup mirrors the overall cohort, underscoring the treatment’s efficacy irrespective of mismatch‑repair status.
- Survival Gap – The 9‑percentage‑point advantage over chemotherapy translates into a clinically meaningful extension of life for a historically difficult‑to‑treat population.
Clinical Implications
- First‑Line Option – The data support lenvatinib‑Pembrolizumab as a durable alternative to single‑agent chemotherapy for platinum‑refractory, advanced endometrial cancer.
- Regulatory Momentum – These results may influence labeling decisions and reimbursement discussions across Europe and beyond.
- Future Research – Ongoing trials are exploring biomarker‑driven sequencing and combination strategies to further improve outcomes.
Forward‑Looking Statements
This release contains forward‑looking statements that involve risks and uncertainties. Actual results may differ materially.-Fineline Info & Tech