Early in 2021 at the American Society of Clinical Oncology’s (ASCO’s) annual meeting, attendees witnessed the first validation of a novel checkpoint target: lymphocyte activation gene 3 (LAG-3). Bristol Myers Squibb’s (BMS’s) recent success in a phase 3 study of the relatlimab anti-LAG-3 monoclonal antibody (MAb) proved that the combination of LAG-3 and programmed cell death protein 1 (PD-1) is more effective than the standard of care in first-line metastatic melanoma (1). For about seven years, that standard has been…