Exelixis, Merck to collaborate on zanzalintinib with Keytruda combination

Exelixis (EXEL) and Merck (MRK) announced that the companies have entered into a clinical development collaboration to evaluate the combination of Exelixis’ investigational tyrosine kinase inhibitor, or TKI, zanzalintinib with Merck’s anti-PD-1 therapy Keytruda in a phase 3 pivotal trial for the treatment of patients with head and neck squamous cell carcinoma, or HNSCC, and zanzalintinib with Welireg, Merck’s oral hypoxia-inducible factor-2 alpha inhibitor, in a phase 1/2 trial and two phase 3 pivotal trials for the treatment of patients with renal cell carcinoma, or RCC. Under the terms of the collaboration, Merck will supply Keytruda for the ongoing, Exelixis-sponsored phase 3 STELLAR-305 pivotal trial in previously untreated PD-L1 positive recurrent or metastatic HNSCC. In addition, Merck will sponsor a phase 1/2 trial and two phase 3 pivotal trials in RCC. Merck will fund one of these phase 3 studies, and Exelixis will co-fund the phase 1/2 trial and the other phase 3 study, as well as supply zanzalintinib and cabozantinib. Exelixis maintains all global commercial and marketing rights to zanzalintinib.