Trials investigating nivolumab and pembrolizumab as anti–PD-1 antibodies, avelumab, durvalumab, and atezolizumab as anti–PD-L1 antibodies, and ipilimumab and tremelimumab as anti–CTLA-4 antibodies for HCC are currently underway [51]. Here, CTLA4 is linked to hepatocellular carcinoma.