Merck & Co., Inc. (MRK.US) terminated a phase III study evaluating the combination of PD-1+TIGIT for the first-line treatment of advanced small cell lung cancer.
August 8, 2023, Merck & Co., Inc. (MRK.US) announced that it will discontinue the Phase III KeyVibe-008 study based on the recommendation of the Independent Data Monitoring Committee (IDMC). The study was designed to evaluate the efficacy and safety of the PD-1+TIGIT combination (vibostolimab+K drug) versus atezolizumab+K drug in the first-line treatment of extensive-stage small cell lung cancer (ES-SCLC).
The primary endpoint of the study was overall survival (OS), and key secondary endpoints included progression-free survival (PFS), objective response rate (ORR), and duration of response (DOR). The prespecified analysis showed that the study did not meet the primary endpoint of OS. In addition, the vibostolimab group had a higher rate of adverse events compared to the control group.
The data showed that vibostolimab is a TIGIT-targeting monoclonal antibody developed by Merck & Co., Inc. that blocks the binding of TIGIT receptor to its ligand (CD112 and CD155) to restore antitumor activity and activate T lymphocytes that help destroy tumor cells.