CD274 and esophageal squamous cell carcinoma: Furthermore, the SKYSCRAPER-07 trial evaluates the efficacy and safety of tiragolumab, a monoclonal antibody designed to bind with TIGIT (a protein receptor on immune cells), plus atezolizumab, a humanized monoclonal antibody immune checkpoint inhibitor that selectively binds to PD-L1, compared with the placebo in participants with localized but unresectable esophageal SCC following definitive concurrent chemoradiotherapy.