Immunoregulatory functions of PD-1/PD-L1 inhibitors and development of resistance to them

This review presents a current understanding of PD-1/PD-L1 inhibitors. In spite of unprecedented clinical efficacy of checkpoint inhibitors in some cancer types, primary or acquired resistance to anti-PD1 therapies is common and affecting up to 60% of patients in some cancer types. The mechanisms that contribute to the development of anti-PD1-/PD-L1 resistance are also discussed.