Non-Immunotherapy Approaches for Relapsed or Refractory AML: An Update for 2024.

Background: Relapsed or refractory (R/R) acute myeloid leukemia (AML) is a challenging, high-risk, clinical scenario with a dismal outcome. Recent insights on the genetic, epigenetic, and metabolic events that drive clonal progression and the advent of novel therapies resulted in the incorporation of several new targeted therapies, alone or in combination, in the R/R setting with the aim of improving response rates and survival. Herein, we review current challenges and future opportunities with non-immunotherapeutic approaches to treat R/R AML.

Summary: Inhibitors of FLT3 and IDH 1/2 are now FDA approved for patients with R/R disease and corresponding mutations. These agents are also used in combination with intensive and low-intensity platforms in an attempt to improve response and survival. Several targeted agents are currently being tested alone or in combination in early-phase trials. These include drugs that target apoptotic pathways, drugs that interfere with key survival pathways of the R/R leukemic cell as well as therapies aimed toward the leukemia marrow microenvironment. Menin inhibitors are a promising class of active drugs in NPM1 and KMT2A-rearranged AML.

Key messages: Several new targeted therapies are being studied and are moving through pre-clinical and clinical pipelines. Significant remaining challenges include the development of synergistic combination therapies tailored to the specific biology and clinical context of the patient, and re-defining the role and timing of allogeneic transplantation in patients with R/R disease.