Overview
11 DESCRIPTION VANFLYTA (quizartinib) is a kinase inhibitor for oral use. The chemical name of quizartinib dihydrochloride is N -(5- tert -butyl-isoxazol-3-yl)- N '-{4-[7-(2-(morpholin-4-ylethoxy)imidazo[2,1- b ][1,3]benzothiazol-2-yl]phenyl}urea dihydrochloride. Quizartinib dihydrochloride is a white to off-white solid with a molecular formula of C 29 H 32 N 6 O 4 S∙2 HCl and a molecular weight...
Mechanism of Action
12 CLINICAL PHARMACOLOGY 12.1 Mechanism of Action Quizartinib is a small molecule inhibitor of the receptor tyrosine kinase FLT3. Quizartinib and its major active metabolite AC886 bind to the adenosine triphosphate (ATP) binding domain of FLT3 with comparable affinity, and both had 10-fold lower affinity towards FLT3-ITD mutation compared to FLT3 in a binding assay. Quizartinib and AC886 inhibited FLT3 kinase activity, preventing autophosphorylation of the receptor, thereby inhibiting downstream FLT3 receptor signaling and blocking FLT3-ITD-dependent cell proliferation. Quizartinib showed antitumor activity in a mouse model of FLT3-ITD-dependent leukemia. 12.
Indications
- 1 INDICATIONS AND USAGE VANFLYTA is indicated in combination with standard cytarabine and anthracycline induction and cytarabine consolidation, and as maintenance monotherapy following consolidation chemotherapy, for the treatment of adult patients with newly diagnosed acute myeloid leukemia (AML) that is FLT3 internal tandem duplication (ITD)-positive as detected by an FDA-approved test [see Dosage and Administration (2.1) and Clinical Studies (14) ] .
Common Doses
- 35.4 mg
- 26.5 mg
- 53 mg
- 0.9 mg
Dosage
2 DOSAGE AND ADMINISTRATION Take VANFLYTA tablets orally once daily with or without food at approximately the same time each day. ( 2.2 ) See Full Prescribing Information for recommended VANFLYTA dosage regimen and dosage modifications. ( 2.2 , 2.3 , 2.4 ) 2.1 Patient Selection Select patients for the treatment of AML with VANFLYTA based on the presence of FLT3-ITD mutation positivity [see Clinical Studies (14) ] . Information on FDA-approved tests for the detection of FLT3-ITD mutation in AML is available at: http://www.fda.gov/CompanionDiagnostics. 2.
Black Box Warning
WARNING: QT PROLONGATION, TORSADES DE POINTES, and CARDIAC ARREST VANFLYTA prolongs the QT interval in a dose- and concentration-related manner [see Clinical Pharmacology (12.2) ] . Prior to VANFLYTA administration and periodically, monitor for hypokalemia or hypomagnesemia, and correct deficiencies. Perform ECGs to monitor the QTc at baseline, weekly during induction and consolidation therapy, weekly for at least the first month of maintenance, and periodically thereafter [see Dosage and Administration (2.3) and Warnings and Precautions (5.1) ].
Contraindications
- 4 CONTRAINDICATIONS VANFLYTA is contraindicated in patients with severe hypokalemia, severe hypomagnesemia, long QT syndrome, or in patients with a history of ventricular arrhythmias or torsades de pointes [see Warnings and Precautions (5.1) ]. Contraindicated in patients with severe hypokalemia, severe hypomagnesemia, long QT syndrome, or in patients with a history of ventricular arrhythmias or torsades de pointes. ( 4 , 5.1 )
Side Effects
- 6 ADVERSE REACTIONS The following clinically significant adverse reactions are described elsewhere in the labeling: QT Prolongation, Torsades de Pointes, and Cardiac Arrest [see Warnings and Precautions (5.1) ] The most common (>20%) adverse reactions, including laboratory abnormalities, are lymphocytes decreased, potassium decreased, albumin decreased, phosphorus decreased, alkaline phosphatase increased, magnesium decreased, febrile neutropenia, diarrhea, mucositis, nausea, calcium decreased, abdominal pain, sepsis, neutropenia, headache, creatine phosphokinase increased, vomiting, and...
Interactions
- 7 DRUG INTERACTIONS Table 7: Effect of Other Drugs on VANFLYTA Strong CYP3A Inhibitors Clinical Impact VANFLYTA is a CYP3A substrate. Concomitant use of VANFLYTA with a strong CYP3A inhibitor increases quizartinib systemic exposure [see Clinical Pharmacology (12.3) ] , which may increase the risk of VANFLYTA adverse reactions. Prevention or Management Reduce the dosage of VANFLYTA [see Dosage and Administration (2.4) ].