Safety profiles of anti-CTLA-4 and anti-PD-1 antibodies alone and in combination.

Inhibition of immune checkpoints using anti-programmed cell death-1 (PD-1) or anti cytotoxic-T-lymphocyte-associated antigen 4 (CTLA-4) monoclonal antibodies has revolutionized the management of patients with advanced-stage melanoma and is among the most promising treatment approaches for many other cancers. Use of CTLA-4 and PD-1 inhibitors, either as single agents, or in combination, has been approved by the US FDA for the treatment of metastatic melanoma. Treatment with these novel immunotherapies results in a unique and distinct spectrum of adverse events, which are mostly related to activation of the immune system and are, therefore, an unwanted consequence of their mechanisms of action.