Gal-3 inhibitors, used either alone or in combination with immune checkpoint blockers or vaccination, have been and also are investigated in phase I-III clinical trials in melanoma, non-small cell lung cancer, squamous cell carcinoma of the head and neck, and chronic lymphocytic leukemia (NCT02575404, NCT02117362, NCT01723813, and NCT00514696). The gene discussed is LGALS3; the disease is B-cell chronic lymphocytic leukemia.