PDCD1 and cancer: The listed trials include participants with both hematologic & solid malignancies; a few of the trials focus on immunocompromised patients, including transplant recipients, patients with human immunodeficiency virus (HIV), or patients with malignancy or autoimmune disease receiving chemotherapy, radiotherapy, anti-PD-1 therapy, anti-PD-L1 therapy, or anti-CD20 therapy.