New approaches for the immunotherapy of acute myeloid leukemia

Acute myeloid leukemia (AML) is a set of related diseases characterized by the immortalization and uncontrolled expansion of myeloid precursor cells. Core therapy for AML has remained unchanged for nearly 30 years, and survival rates remain unsatisfactory. However, advances in the immunotherapy of AML have created opportunities for improved outcomes. Enforcing a tumor-specific immune response through the re-direction of the adaptive immune system, which links remarkable specificity with potent cytotoxic effector functions, has proven particularly compelling. This may be coupled with immune checkpoint blockade and conventional therapies for optimal effect. Engineered antibodies are currently in use in AML and the repertoire of available therapeutics will expand. NK cells have shown effectiveness in this disease. New methods to optimize their activation and the targeting of AML show potential. Most significantly, adoptive immunotherapy with tumor-specific T cells, and particularly T cells re-directed using genetically introduced TCR or chimeric antigen receptors, have demonstrated promise. Each of these approaches has unique benefits and challenges that we explore in this review.