An Overview of Targeted Therapies in Acute Myeloid Leukemia

Abstract

Acute myeloid leukemia (AML) is the most aggressive adult leukemia, characterized by clonal differentiation arrest of progenitor or precursor hematopoietic cells. Intense preclinical and clinical research has led to regulatory approval of several targeted therapeutics, administered either as single agents or as combination therapies. However, the majority of patients still face a poor prognosis and disease relapse frequently occurs due to selection of therapy-resistant clones. Hence, more effective novel therapies, most likely as innovative, rational combination therapies, are urgently needed. Chromosomal aberrations, gene mutations, and epigenetic alterations drive AML pathogenesis but concurrently provide vulnerabilities to specifically target leukemic cells. Other molecules, either aberrantly active and/or overexpressed in leukemic stem cells, may also be leveraged for therapeutic benefit. This concise review of targeted therapies for AML treatment, which are either approved or are being actively investigated in clinical trials or recent preclinical studies, provides a flavor of the direction of travel, but also highlights the current challenges in AML treatment.

Induction of AML cell differentiation using HOXA9/DNA binding inhibitors as a potential therapeutic option for HOXA9‐dependent AML

“…Given that conventional chemotherapy is still the standard AML treatment, the need for new targeted therapies, especially against various AML subtypes like those involving HOXA9, remains imperative. Among the newly approved or evaluated treatments, 2 , 3 differentiation therapies have indeed proved effective in the clinic such as the mitochondrial protein IDH2 (isocitrate dehydrogenase‐2) inhibitor enasidenib (AG221, Celgene), 5 , 38 the IDH1 inhibitor Ivosidenib (AG‐120, Agios), 5 , 39 lysine‐specific demethylase 1 (LSD1) inhibitors 40 , 41 such as tranylcypromine and analogs 32 , 42 or ORY‐1001, 3 , 43 , 44 , 45 or the DOT1L inhibitor pinometostat (EPZ‐5676) 7 , 17 , 46 , 47 known to downregulate HOXA9 expression. 48 More recently the Menin/MLL inhibitor revumenib (SNDX‐5613) showed promising results against the HOXA9‐dependant MLL subtypes of AML, 6 , 49 but it also led to resistance.…”

“… 48 More recently the Menin/MLL inhibitor revumenib (SNDX‐5613) showed promising results against the HOXA9‐dependant MLL subtypes of AML, 6 , 49 but it also led to resistance. 50 Overcoming this resistance and other expected ones will require new drugs, 3 , 4 with one approach being the direct targeting of HOXA9 function as a common downstream effector of differentiation blockade. 10 HOXA9 is an interesting oncogenic target since it is not or only slightly expressed in healthy adult tissues, except in hematopoietic stem cells.…”

“…Among approved or clinically tested targeted therapies are FLT3-mutated, P53-mutated, IDH-mutated or BCL2 inhibitors, cereblon E3-ligase modulators, and monoclonal antibodies (anti-CD33, CD123 ± CD3, CD47, CTLA4, PD-1, or TIM3). 3,4 Additionally, the development of small molecule inhibitors aiming to induce AML cell differentiation to mirror the success of all-trans-retinoic-acid (ATRA/Tretinoïne/Vesanoid®) and arsenic trioxide (ATO/Trisenox®) targeting the PML-RARα fusion transcription factor in acute promyelocytic leukemia (APL, AML-M3) is an attractive strategy leading to the development of IDH1 (Ivosidenib/AG-120/Tibsovo®) or IDH2 (Enasidenib/AG-221/Idhifa®) mutants inhibitors, or epigenetic modulators against the menin/MLL interaction like Revumenib/SNDX-5613, Ziftomenib/KO-539 or JNJ-6617, or targeting DOT1L histone methyltransferase (Pinometostat/EPZ-5676). [5][6][7] While transcription factors play a key role in regulating the expression of oncogenic-associated genes, the direct targeting of these factors by antitumor molecules remains limited.…”

Machine Learning Predicts 30-Day Outcome among Acute Myeloid Leukemia Patients: A Single-Center, Retrospective, Cohort Study

“…Chemotherapy (CTx) measures include standard 3 + 7 therapy (Standard CTx), FLAG (fludarabine, anthracycline, G-CSF), hypomethylating agents (HMA), low-dose cytarabine (LDAR), mitoxantrone, etoposide, and cytarabine combination CTx (MEC), which could be applied to patients considering age, organ dysfunction, and performance status [ 7 , 8 , 9 , 10 ]. Targeted therapy based on tumor neoantigens with respect to genetic mutations is under current development and is entering the clinical field [ 11 , 12 , 13 , 14 , 15 ]. Hematopoietic stem cell transplantation could be performed for eligible patients and could be a curative measure.…”

Acute Myelomonoblastic Leukemia (My1/De): A Preclinical Rat Model

“…Even though recent decades witnessed great advancements in understanding the pathological processes of acute myeloid leukemia (AML), this hematologic malignancy still remains the most aggressive type of adult acute leukemia (1). Owing to their inherent ability to resemble primary tumorigenesis and metastatic spread, preclinical leukemic models hold great promise in revealing clinically relevant complementary information on AML-associated genetic, cellular as well as immunological abnormalities.…”