TIM-3: a tumor-associated antigen beyond checkpoint inhibition?

Immune checkpoint inhibitors are one of the most remarkable immunomodulatory therapies of current times. Sabatolimab is a high-affinity, humanized anti-TIM-3 monoclonal antibody currently in development for patients with myeloproliferative disorders, including acute myeloid leukemia and myelodysplastic syndromes. By targeting TIM-3, a receptor expressed on various immune effector cells as well as myeloid cells, multiple mechanisms of action that are distinct from canonical immune checkpoint inhibitors are in play - (i) blockade of TIM-3 and its ligands PtdSer/galectin-9, (ii) modulation of leukemic cell self-renewal as well as (iii) antibody-dependent phagocytosis of TIM-3-expressing leukemic cells. Novel immunotherapies such as sabatolimab which enhance the antitumor immune response on converging fronts represent the promise of a continuously replenished armoury for the treatment of cancer.