Merck (NYSE:MRK), known as MSD outside of the United States and Canada, and Eisai today announced results from the Phase 3 LITESPARK-012 trial evaluating combination regimens for the first-line treatment of patients with advanced clear cell renal cell carcinoma (RCC). The trial evaluated the triplet therapy of KEYTRUDA® (pembrolizumab), Merck's anti-PD-1 therapy, plus LENVIMA® (lenvatinib), the orally available multiple receptor tyrosine kinase inhibitor (TKI) discovered by Eisai, plus WELIREG® (belzutifan), Merck's first-in-class, oral hypoxia-inducible factor-2 alpha (HIF-2α) inhibitor. The study also evaluated MK-1308A, the coformulation of KEYTRUDA and quavonlimab, Merck's investigational anti-CTLA-4 antibody, plus LENVIMA. Both combination regimens were compared to KEYTRUDA plus LENVIMA for these patients.

At a pre-specified interim analysis, the combination regimens did not meet the dual primary endpoints of progression-free survival (PFS) and overall survival (OS) for the first-line treatment of patients with RCC compared to KEYTRUDA plus LENVIMA. The safety profiles of the combination regimens were consistent with those observed in previously reported studies evaluating the individual medicines and the KEYTRUDA plus LENVIMA combination. A full evaluation of the data from this study is ongoing, and Merck and Eisai will work with investigators to share the results with the scientific community.