Current Hematologic Malignancy Reports

, Volume 9, Issue 2, pp 174–185 | Cite as

FLT3 Inhibitors in AML: Are We There Yet?

Acute Leukemias (R Stone, Section Editor)

Abstract

FMS-like tyrosine kinase 3 (FLT3) is the most frequently mutated gene in AML. Thirty percent of patients with acute myeloid leukemia (AML) harbor activating mutations in FLT3, either internal tandem duplication mutations in the juxtamembrane domain (FLT3-ITD) or point mutations in the tyrosine kinase domain (FLT3 TKD). Small molecule FLT3 inhibitors have emerged as an attractive therapeutic option in patients with FLT3 mutations; however, the clinical activity of early inhibitors was limited by a lack of selectivity, potency and unfavorable pharmacokinetic properties. Newer agents such as quizartinib have improved potency and selectivity associated with much higher bone marrow response rates; however, response duration is limited by the development of secondary resistance. We will review here a number of FLT3 inhibitors that have been evaluated in clinical trials and discuss challenges facing the use of these agents in AML.

Keywords

AML FLT3-ITD FLT3 mutation FLT3 inhibitor Midostaurin Lestaurtinib Sunitinib Sorafenib Quizartinib PLX3397 Ponatinib Resistance 

Notes

Compliance with Ethics Guidelines

Conflict of Interest

Dr. Akshay Sudhindra declares no potential conflicts of interest relevant to this article.

Dr. Catherine Choy Smith received research funding from Plexxikon and has a patent pending for discovery of AC220-resistant mutations.

Human and Animal Rights and Informed Consent

This article does not contain any studies with human or animal subjects performed by any of the authors.

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© Springer Science+Business Media New York 2014

Authors and Affiliations

  1. 1.University of California, San FranciscoSan FranciscoUSA

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