Drug Interactions between cabozantinib and probucol

MONITOR CLOSELY: Cabozantinib can cause prolongation of the QT interval. In a randomized, double-blinded, placebo-controlled study of patients with medullary thyroid cancer, a cabozantinib dose of 140 mg was administered orally once a day. After 4 weeks at this dose, a mean increase in QTcF (corrected QT interval by Fridericia) from baseline of 10 to 15 ms was observed. Theoretically, coadministration with other agents that can prolong the QT interval may result in additive effects and increased risk of ventricular arrhythmias including torsade de pointes and sudden death. In general, the risk of an individual agent or a combination of agents causing ventricular arrhythmia in association with QT prolongation is largely unpredictable but may be increased by certain underlying risk factors such as congenital long QT syndrome, cardiac disease, and electrolyte disturbances (e.g., hypokalemia, hypomagnesemia). In addition, the extent of drug-induced QT prolongation is dependent on the particular drug(s) involved and dosage(s) of the drug(s).

MANAGEMENT: Caution and close clinical monitoring are recommended if cabozantinib is used in combination with other drugs that can prolong the QT interval. Patients should be advised to seek prompt medical attention if they experience symptoms that could indicate the occurrence of torsade de pointes such as dizziness, lightheadedness, fainting, palpitation, irregular heart rhythm, shortness of breath, or syncope.