Background: Despite improvements in the management of locally advanced or metastatic non–small cell lung cancer (NSCLC) from programmed cell death/ligand protein 1 (PD-[L]1) inhibition, there remains an unmet need for improved treatment options. PD-L1 expression is a known biomarker of response to anti–PD-L1 therapies in metastatic NSCLC. The combination of PD-1 inhibition with inhibition of the immunosuppressive T cell Immunoglobulin and ITIM domain (TIGIT) pathway is associated with improved response and prolonged progression-free survival in patients with advanced NSCLC. Domvanalimab (dom) is an Fc-silent humanized IgG1 monoclonal antibody (mAb) that blocks TIGIT, thereby reducing immunosuppression of T/natural killer (NK) cells and promoting antitumor activity. Zimberelimab (zim) is an mAb that binds to PD-1 on T/NK cells, preventing PD-L1-mediated immunosuppressive effects and resulting in tumor cell death. This phase 3 study will investigate the efficacy and safety of combination therapy with dom + zim compared with pembrolizumab monotherapy in patients with PD-L1-high NSCLC. Methods: ARC-10 (NCT04736173) is a global, phase 3, randomized, multicenter, open-label study. Eligible patients are adults with histologically confirmed, treatment-naive, locally advanced or metastatic, squamous or non-squamous NSCLC with ≥1 measurable lesion(s) per Response Evaluation Criteria in Solid Tumors (RECIST) v1.1, high expression of PD-L1 (tumor cells [TC] ≥50%), and an Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1. Patients must not have genomic tumor aberrations for which targeted therapies are approved and available (eg, EGFR, ALK, ROS, BRAF, NTRK). Approximately 600 patients will be randomized 1:1 to receive combination therapy with dom + zim (dom 1200 mg intravenous [IV] once every 3 weeks [Q3W] + zim 360 mg IV Q3W) or pembrolizumab monotherapy (200 mg IV Q3W) for 21-day cycles until disease progression, intolerance, or a maximum of 35 cycles. Randomization will be stratified by ECOG performance status (0 vs 1), geographical region (Asia vs non-Asia), and histology (squamous vs non-squamous). The primary efficacy endpoint is overall survival. Secondary efficacy endpoints include blinded independent central review of progression-free survival and confirmed overall response rate according to RECIST v1.1. Safety endpoints include the presence of treatment-emergent adverse events and laboratory parameters. Health-related quality of life will be assessed by measuring the time to first symptom deterioration in the NSCLC-Symptom Assessment Questionnaire total score. Study recruitment is planned in Asia, North and South America, Africa, and Europe. Clinical trial information: NCT04736173.