Exelixis, Inc. (Nasdaq: EXEL) and Merck (NYSE: MRK), known as MSD outside the U.S. and Canada, have announced a clinical development collaboration. The partnership will evaluate the investigational tyrosine kinase inhibitor (TKI) zanzalintinib in combination with Merck’s anti-PD-1 therapy KEYTRUDA® (pembrolizumab) in a phase 3 pivotal trial for patients with head and neck squamous cell carcinoma (HNSCC). Additionally, they will study zanzalintinib with WELIREG® (belzutifan), Merck’s oral hypoxia-inducible factor-2 alpha (HIF-2α) inhibitor, in a phase 1/2 trial and two phase 3 pivotal trials for renal cell carcinoma (RCC).
“This collaboration highlights our confidence in zanzalintinib’s potential to benefit patients when combined with immunotherapy or targeted therapy for head and neck squamous cell carcinoma (HNSCC) and renal cell carcinoma (RCC), where there are significant unmet needs,” said Amy Peterson, M.D., Executive Vice President and Chief Medical Officer at Exelixis. “KEYTRUDA and WELIREG have already improved outcomes for some cancer patients, and we are excited to work with Merck’s clinical team to explore the potential of these therapies combined with zanzalintinib. This partnership facilitates further development of zanzalintinib in RCC.”
Dr. Marjorie Green, Senior Vice President and Head of Oncology at Merck, added, “We look forward to collaborating with Exelixis to advance these clinical trials. Merck is committed to enhancing patient outcomes by strategically evaluating new combination therapies.”
Under the agreement, Merck will provide KEYTRUDA for Exelixis’ ongoing phase 3 STELLAR-305 trial for previously untreated PD-L1 positive recurrent or metastatic HNSCC. Merck will also sponsor a phase 1/2 trial and two pivotal phase 3 trials in RCC, funding one of the phase 3 studies. Exelixis will co-fund the phase 1/2 trial and the other phase 3 study while supplying zanzalintinib and cabozantinib. Exelixis retains all global commercial rights to zanzalintinib.
About Head and Neck Cancer
Head and neck cancer encompasses various tumors in the throat, larynx, nose, sinuses, and mouth. Most are squamous cell carcinomas, which originate in the thin surface layer of these structures. Major risk factors include tobacco and alcohol use, as well as human papillomavirus (HPV). In 2022, over 891,500 new cases and more than 458,100 deaths were reported globally. In the U.S., estimates for 2024 include over 58,450 new cases and more than 12,230 deaths.
About Renal Cell Carcinoma
Renal cell carcinoma (RCC) is the most prevalent form of kidney cancer, making up about 90% of diagnoses. It occurs more frequently in men than women and is often discovered incidentally during imaging for other conditions. RCC has a high recurrence risk, with up to 40% of newly diagnosed patients experiencing recurrence within five years of surgery. In the U.S., approximately 81,600 new cases and 14,400 deaths from kidney cancer are anticipated in 2024.
About Zanzalintinib
Zanzalintinib targets multiple cancer-related pathways involved in resistance to therapies, including immune checkpoint inhibitors. Promising results from the phase 1b STELLAR-001 clinical trial were shared at the 2023 International Kidney Cancer Symposium.
About KEYTRUDA® (pembrolizumab)
KEYTRUDA is an anti-PD-1 therapy that enhances the immune system’s ability to detect and combat tumor cells. It blocks the interaction between PD-1 and its ligands, PD-L1 and PD-L2, thereby activating T lymphocytes to target both tumor and healthy cells. Merck leads the industry with over 1,600 clinical trials studying KEYTRUDA across various cancers and treatment settings, aiming to understand its role and identify predictive biomarkers for patient benefit.
