QT Prolongation, Torsades DE Pointes, and Cardia Arrest

• VANFLYTA prolongs the QT interval in a dose- and concentration-related manner [see Clinical Pharmacology]. 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 and Warnings and Precautions].
• Torsades de pointes and cardiac arrest have occurred in patients receiving VANFLYTA. Do not administer VANFLYTA to patients with severe hypokalemia, severe hypomagnesemia, or long QT syndrome [see Contraindications and Warnings and Precautions].
• Do not initiate treatment with VANFLYTA or escalate the VANFLYTA dose if the QT interval corrected by Fridericia’s formula (QTcF) is greater than 450 ms [see Dosage and Administration and Warnings and Precautions].
• Reduce the VANFLYTA dose when used concomitantly with strong CYP3A inhibitors, as they may increase quizartinib exposure [see Dosage and Administration and Warnings and Precautions].