A Study of Valemetostat Tosylate Plus Pembrolizumab Versus Pembrolizumab Alone in First-Line NSCLC Without Actionable Genomic Alterations

This trial will evaluate the safety and efficacy of valemetostat tosylate (DS-3201b) in combination with fixed-dose pembrolizumab versus pembrolizumab alone in participants with advanced or metastatic NSCLC without actionable genomic alterations, whose tumor has PD-L1 TPS ≥50%, and who have not received prior systemic therapy for advanced or metastatic NSCLC. The trial will be in 2 phases, dose escalation and dose expansion phases.