Acute Myeloid Leukemia Therapy Approved by FDA

The FDA has approved Daiichi Sankyo’s Vanflyta (quizartinib) to treat adult patients with newly diagnosed acute myeloid leukemia (AML).¹ It is indicated to be used in combination with standard cytarabine and anthracycline induction and cytarabine consolidation, and as maintenance monotherapy following consolidation chemotherapy. Vanflyta is oral inhibitor of FLT3, and it specifically targets FLT3-ITD mutations, which drive cancer growth and contribute to increased risk of relapse and shorter overall survival.

AML is one of the most common forms of leukemia in adults and an estimated 20,380 new cases will be diagnosed in the United States in 2023. Up to 37% of newly diagnosed patients with AML have a mutation of the FLT3 gene (FMS-like tyrosine kinase 3). About 80% of these are FLT3-ITD mutations.

Vanflyta will be available by prescription in the coming weeks. The wholesale acquisition cost (WAC) is $546.00 per tablet for both the 17.7 mg and 26.5 mg dose — or $199,290 annually. A spokesperson for Daiichi Sankyo said the price reflects the clinical innovation and potential therapeutic benefit for newly diagnosed FLT3-ITD positive AML across three phases of treatment – induction, consolidation and maintenance in patients without transplant.

“The approval of VANFLYTA represents a significant advancement for the treatment of patients with newly diagnosed FLT3-ITD positive AML, which is one of the most aggressive and difficult-to-treat subtypes,” Harry P. Erba, M.D., Ph.D., professor of medicine, Department of Medicine, Division of Hematologic Malignancies and Cellular Therapy, Duke Cancer Institute, said in a press release.¹

The approval was based on results of the QuANTUM-First trial published in The Lancet.² In the trial, Vanflyta combined with cytarabine and anthracycline induction and cytarabine consolidation resulted in a 22% reduction in the risk of death compared with standard chemotherapy alone in patients with newly diagnosed FLT3-ITD positive AML. While complete remission (CR) rates were similar between both arms of the trial, the median duration of complete remission was more than three times longer at 38.6 months for patients receiving Vanflyta compared with 12.4 months for those receiving placebo plus standard chemotherapy alone.

Vanflyta is approved with a boxed warning for QT prolongation (which increases the risk of arrhythmia), torsades de pointes (a type of abnormal heart rhythm) and cardiac arrest. Treatment emergent QT interval prolongation events of any grade were reported in 14% of patients who received Vanflyta, including 3.0% who experienced a grade 3 or 4 event.

Vanflyta is not indicated as maintenance monotherapy following allogeneic hematopoietic stem cell transplantation.

This article originally appeared on Formulary Watch.

References

1. VANFLYTA® First FLT3 Inhibitor Approved in the U.S. Specifically for Patients with Newly Diagnosed FLT3-ITD Positive AML. News Release. Daiichi Sankyo. July 20, 2023. Accessed July 31, 2023. https://daiichisankyo.us/press-releases/-/article/vanflyta-first-flt3-inhibitor-approved-in-the-u-s-specifically-for-patients-with-newly-diagnosed-flt3-itd-positive-aml

2. Erba HP, Montesinos P, Kim H-J, et al. Quizartinib plus chemotherapy in newly diagnosed patients with FLT3-internal-tandem-duplication-positive acute myeloid leukaemia (quantum-first): A randomised, double-blind, placebo-controlled, phase 3 trial. The Lancet. 2023;401(10388):1571-1583. doi:10.1016/s0140-6736(23)00464-6