Drug Interaction Report

MONITOR: Coadministration with inducers of CYP450 3A4 may decrease the plasma concentrations of panobinostat, which is partially metabolized by the isoenzyme. The interaction has not been evaluated clinically, but simulations using physiologically-based pharmacokinetic (PBPK) models suggest an approximately 70% decrease in panobinostat systemic exposure in the presence of potent CYP450 3A4 inducers.

MANAGEMENT: Caution is advised during concomitant use of panobinostat with CYP450 3A4 inducers. The potential for decreased efficacy of panobinostat should be considered.

GENERALLY AVOID: Grapefruit juice may increase the plasma concentrations of panobinostat. The proposed mechanism is inhibition of CYP450 3A4-mediated first-pass metabolism in the gut wall by certain compounds present in grapefruit. Increased exposure to panobinostat may increase the risk of adverse effects such as nausea, vomiting, diarrhea, anorexia, peripheral edema, cardiotoxicity, ECG abnormalities, electrolyte disturbances, bleeding complications, hepatotoxicity, and myelosuppression.

Food may delay the rate of absorption of panobinostat, but does not significantly affect the overall extent of absorption. When a single oral dose of panobinostat was administered to 36 patients with advanced cancer 30 minutes after a high-fat meal, panobinostat peak plasma concentration (Cmax) and systemic exposure (AUC) were approximately 44% and 16% lower, respectively, compared to administration under fasting conditions. The median time to maximum concentration (Tmax) was prolonged by 2.5 hours.

MANAGEMENT: Patients should avoid consumption of grapefruit or grapefruit juice during treatment with panobinostat. The manufacturer also recommends avoiding star fruit, Seville oranges, pomegranate, and pomegranate juice. Panobinostat may be administered with or without food.

MONITOR: Coadministration of two or more sympathomimetic agents may increase the risk of adverse effects such as nervousness, irritability, and increased heart rate. Central nervous system (CNS) stimulants, particularly amphetamines, can potentiate the adrenergic response to vasopressors and other sympathomimetic agents. Additive increases in blood pressure and heart rate may occur due to enhanced peripheral sympathetic activity.

MANAGEMENT: Caution is advised if two or more sympathomimetic agents are coadministered. Pulse and blood pressure should be closely monitored.