Combination of CTLA-4 and PD-1/PD-L1 Immune Checkpoints Inhibitors for Treatment of Cancer

Blockade checkpoints of immune cell activation has been illustrated to be the most powerful approach for activation of anticancer immune responses.PD-1 and CTLA-4 checkpoints have mainly on activated T-cells to be the most solid targets for the cancer treatment.The drugs when administered as monotherapy had substantial increase in durable response rates and had possible safety profile, but 50 % or more of patients failed to respond to treatment.Combination of CTLA-4 and PD-1 blockers was estimated to increase the response rates, and ipilimumab (anti-CTLA-4) plus nivolumab (anti-PD-1) combination was seen to importantly boost efficiency in metastatic melanoma patients.The success of combination immune checkpoints therapy motivated several clinical examinations in other cancer types.