PDCD1 and neoplasm: As LAG-3 is frequently co-expressed with PD-1 in tumor infiltrating lymphocytes, combined efficacy of PD-1 and LAG-3 blockade (NCT03005782 and NCT02061761) or a bispecific antibody against PD-1 and LAG-3 (NCT03219268) are actively being investigated in various types of malignancies including blood cancers.