FLT3 inhibitor quizartinib improves survival in FLT3-ITD AML
Although the multikinase inhibitor midostaurin was approved in 2017 for the treatment of newly diagnosed, FLT3-mutated AML, there is no approved targeted therapy in the relapsed/refractory (R/R) setting. Quizartinib is a second-generation, highly potent and selective FLT3 inhibitor that demonstrated antileukemic activity in phase 1 and 2 trials.
Professor Jorge Cortes (MD Anderson Cancer Center, Houston, USA) presented the first results of the phase 3 QuANTUM-R trial comparing single-agent quizartinib to standard chemotherapy (loDAC, FLAG-IDA, or MEC) in R/R AML with FLT3-internal tandem duplication (ITD; ≥3% allelic ratio). Patients who responded were allowed to continue to hematopoietic stem cell transplantation (HSCT), and patients in the quizartinib arm were allowed to receive quizartinib again post HSCT.
Cortes: “Single-agent quizartinib significantly prolonged overall survival (OS) in patients with R/R FLT3-ITD-mutated AML compared to standard chemotherapy, with a median OS of 6.2 vs. 4.7 months (HR 0.76, p=0.0177).” The drug was well tolerated, with a very low frequency (3%) of grade ≥3 QTcF prolongation. “QuANTUM-R is the first phase 3 study that shows a significant improvement in OS for a single agent, here a FLT3 inhibitor, in this population of R/R FLT3-ITD-mutated AML.”