Relatlimab (BMS-986016, Bristol-Myers Squibb, New York, NY, USA), a human IgG4 anti-LAG3 blocking mAb is currently being evaluated in several phase I and II/III clinical trials in solid tumors and hematological malignancies, including CLL (ClinicalTrials.gov Identifier: NCT02061761), alone or in combination with anti-PD-1/PD-L1 blocking mAbs [32]. This evidence concerns the gene CD274 and B-cell chronic lymphocytic leukemia.