Drug Interactions between fluconazole and gilteritinib

The use of fluconazole has been rarely associated with hepatotoxicity. Reversible idiosyncratic hepatitis, cholestasis and fatal fulminant hepatic failure have been reported, the latter occurring primarily in patients with serious underlying medical conditions and taking multiple concomitant medications. Liver function tests should be performed periodically in patients with preexisting hepatic abnormalities, particularly during prolonged therapy. Treatment should be withdrawn if persistent elevations or worsening of liver enzyme levels occur.

Some azole antifungals have been associated with prolongation of the QT interval on the ECG. Rare cases of QT prolongation and torsade de pointes have been reported during postmarketing experience; such reports usually involved seriously ill patients with multiple confounding risk factors, such as structural heart disease, electrolyte abnormalities, and concomitant medications. These drugs should be administered with caution to patients with potentially proarrhythmic conditions, such as congenital/acquired QT prolongation, cardiomyopathy (especially when heart failure is present), sinus bradycardia, and existing symptomatic arrhythmias. Concomitant use with other medications that have potential to increase the risk of cardiotoxicity should be avoided.

Fluconazole is substantially removed by hemodialysis. Plasma levels of fluconazole has been shown to reduce by 50% following 3 hours of dialysis. Fluconazole should be administered after hemodialysis.

Gilteritinib has been associated with prolonged cardiac ventricular repolarization (QT interval). Perform electrocardiogram (ECG) prior to initiation of treatment with gilteritinib, on days 8 and 15 of cycle 1, and prior to the start of the next two subsequent cycles. Interrupt and reduce the dosage of gilteritinib in patients who have a QTcF >500 msec. Hypokalemia or hypomagnesemia may increase the QT prolongation risk. Correct hypokalemia or hypomagnesemia prior to and during treatment administration.

The effect of severe hepatic (Child-Pugh Class C) or severe renal impairment (Clcr = 29 mL/min) on gilteritinib pharmacokinetics is unknown.

Gilteritinib has been associated with prolonged cardiac ventricular repolarization (QT interval). Perform electrocardiogram (ECG) prior to initiation of treatment with gilteritinib, on days 8 and 15 of cycle 1, and prior to the start of the next two subsequent cycles. Interrupt and reduce the dosage of gilteritinib in patients who have a QTcF >500 msec. Hypokalemia or hypomagnesemia may increase the QT prolongation risk. Correct hypokalemia or hypomagnesemia prior to and during treatment administration.

Gilteritinib has been associated with prolonged cardiac ventricular repolarization (QT interval). Perform electrocardiogram (ECG) prior to initiation of treatment with gilteritinib, on days 8 and 15 of cycle 1, and prior to the start of the next two subsequent cycles. Interrupt and reduce the dosage of gilteritinib in patients who have a QTcF >500 msec. Hypokalemia or hypomagnesemia may increase the QT prolongation risk. Correct hypokalemia or hypomagnesemia prior to and during treatment administration.

Fluconazole is primarily eliminated by the kidney. Patients with renal impairment may be at greater risk for adverse effects from fluconazole due to decreased drug clearance. Dosage adjustments are recommended for patients with moderate to severe renal impairment (CrCl <= 50 mL/min) receiving multiple doses of the drug.

The effect of severe hepatic (Child-Pugh Class C) or severe renal impairment (Clcr = 29 mL/min) on gilteritinib pharmacokinetics is unknown.