Additionally, several phase I trials include the use of IL-15 with nivolumab (anti-PD-1) and ipilimumab (anti-cytotoxic T-lymphocyte associated protein 4 [CTLA4]) in refractory cancers (NCT03388632), with avelumab (anti-PD-L1) in T cell malignancies (NCT03905135), with obinutuzumab (anti-CD20) in chronic lymphocytic leukemia (NCT03759184), and with alemtuzumab (anti-CD52) in adult T-cell leukemia (NCT02689453). Here, PDCD1 is linked to cancer.