Merck Expands Kidney Cancer Treatment Welireg to Broader Patient Group

Merck has expanded the use of its cancer treatment Welireg to a broader set of kidney cancer patients. The FDA approved Welireg in combination with Eisai's Lenvima for certain kidney cancer patients on Friday, September 25, 2026.

The approval marks an expansion of Welireg's existing label, which previously only covered specific types of kidney cancer patients who had failed prior therapy. With this new approval, the treatment will now be available to a wider range of patients with renal cell carcinoma (RCC), including those who have not received prior therapy.

Welireg was initially approved in 2022 as a monotherapy for adult patients with RCC who were at risk of disease progression. The treatment has since shown promising results in combination with other therapies, leading to this latest expansion of its label.