VANFLYTA carries significant risks, primarily QT prolongation, Torsades de Pointes, and cardiac arrest, necessitating strict monitoring and adherence to a Risk Evaluation and Mitigation Strategy (REMS).

Critical Safety Monitoring and Contraindications for VANFLYTA

Before initiating VANFLYTA, and periodically thereafter, electrocardiograms (ECGs) must be performed to monitor the QTcF interval; treatment should not start if QTcF > 450 ms. Electrolyte imbalances (hypokalemia, hypomagnesemia) must be corrected and monitored. VANFLYTA is contraindicated in patients with severe hypokalemia, severe hypomagnesemia, long QT syndrome, or a history of ventricular arrhythmias or Torsades de Pointes. Concomitant use with strong CYP3A inhibitors requires VANFLYTA dose reduction, while use with strong or moderate CYP3A inducers should be avoided. The drug is only available through the VANFLYTA REMS program due to these cardiac risks. Embryo-fetal toxicity is also a concern, requiring contraception.