CTLA4 and cancer: Immune checkpoint inhibitors (ICIs) employed for cancer therapy include PD-1 (pembrolizumab, nivolumab, cemiplimab, dostarlimab), PDL-1 (atezolizumab, avelumab, durvalumab), CTLA-4 (ipilimumab, tremelimumab), and the recently approved LAG-3 antibodies (relatlimab).