Drug Interaction Report

Coadministration with potent inhibitors of CYP450 3A4 may significantly increase the plasma concentrations of netupitant. When a single 300 mg-0.5 mg dose of netupitant-palonosetron was administered following 400 mg once daily administration of the potent CYP450 3A4 inhibitor ketoconazole for 12 days, mean netupitant peak plasma concentration (Cmax) and systemic exposure (AUC) increased by 25% and 140%, respectively, while mean Cmax and AUC of palonosetron increased by 15% and 10%, respectively. No dosage adjustment is necessary for single-dose administration of netupitant-palonosetron when used with potent CYP450 3A4 inhibitors. However, patients may experience increased adverse effects such as headache, asthenia, dyspepsia, fatigue, constipation, and erythema.