Merck & Co. won FDA approval for Welireg (belzutifan) plus Keytruda (pembrolizumab) in an adjuvant setting for high-risk clear cell renal cell carcinoma after surgery. The June 12 nod marks the first approval for a PD-1 plus HIF-2 alpha inhibitor combination used as adjuvant therapy in ccRCC. The approval is based on the pivotal Litespark-022 trial, which enrolled 1,841 patients and reported a 28% reduction in the risk of disease recurrence, metastasis, or death versus Keytruda plus placebo. Disease-free survival estimates were 81% in the Welireg-Keytruda arm versus 74% in the control arm, though overall survival data were described as not yet mature. Merck’s result extends the company’s post-Keytruda strategy deeper into earlier-stage renal cell carcinoma and provides a new combination option for intermediate-high and high recurrence-risk patients.