Figure 2.

Combination therapies with anti-PD-1/PD-L1 antibodies. Because of the complexity of the tumor microenvironment and the complexity of checkpoint regulation in TILs, only partially successful clinical results of PD-1/PD-L1 blockade have been achieved in certain tumors. Therefore, combination therapies are required. Ongoing studies, such as using PD-1/PD-L1 antibodies combined with other checkpoint antibodies, tumor vaccines, antiviral drugs, anti-microbiome modulation, chemotherapy and radiation therapies, or kinase or enzyme inhibitors are being developed. Combination therapies will be a future direction for cancer patient treatment.