In a Merck Litespark trial, the Welireg (belzutifan) triplet with Keytruda (pembrolizumab) and Lenvima (lenvatinib) missed both progression-free survival (PFS) and overall survival (OS) endpoints in first-line advanced renal cell carcinoma (RCC). 2
This refers to the phase 3 LITESPARK-012 trial evaluating Welireg added to Keytruda plus Lenvima in the first-line setting. 3578
In contrast, Welireg plus Lenvima succeeded in LITESPARK-011 for previously treated advanced RCC, meeting PFS endpoint vs. cabozantinib. 357
Welireg is approved for late-line RCC post PD-1/L1 and VEGF therapy based on LITESPARK-005, showing significant PFS benefit. 14
Sources:
1. https://www.oncologypipeline.com/apexonco/merck-vs-merck-late-line-kidney-cancer
2. https://www.fiercepharma.com/pharma/merck-litespark-shocker-welireg-triplet-misses-mark-first-line-kidney-cancer
3. https://www.eisai.com/news/2026/news202611.html
4. https://cancerletter.com/clinical-roundup/20230908_8e/
5. https://www.merck.com/news/merck-and-eisai-announce-welireg-belzutifan-plus-lenvima-lenvatinib-met-primary-endpoint-of-progression-free-survival-pfs-in-certain-previously-treated-patients-with-advanced-renal-c/
7. https://www.merck.com/news/welireg-belzutifan-plus-lenvima-lenvatinib-reduced-the-risk-of-disease-progression-or-death-by-30-compared-to-cabozantinib-in-certain-previously-treated-patients-with-advanced-renal-ce/