Drug Interactions between infigratinib and suvorexant

ADJUST DOSING INTERVAL: Food may increase the oral bioavailability of infigratinib. Coadministration with a high-fat, high-calorie meal (800 to 1,000 calories, with approximately 50% of total calories from fat) in healthy subjects increased mean infigratinib peak plasma concentration (Cmax) and total systemic exposure (AUC) by 60% to 80% and 80% to 120%, respectively, and increased the median time to Cmax from 4 hours to 6 hours. When coadministered with a low-fat, low-calorie meal (approximately 330 calories, with 20% of total calories from fat), mean infigratinib Cmax and AUC increased by 90% and 70%, respectively, while the median time to Cmax did not change.

GENERALLY AVOID: Grapefruit juice may increase the plasma concentrations of infigratinib and one of its active metabolites, BHS697, both of which are primarily metabolized by CYP450 3A4 in vitro. The proposed mechanism is inhibition of CYP450 3A4-mediated first-pass metabolism in the gut wall by certain compounds present in grapefruit. Inhibition of hepatic CYP450 3A4 may also contribute. The interaction has not been studied with grapefruit juice but has been reported for other CYP450 3A4 inhibitors. Coadministration of infigratinib with multiple doses of itraconazole, a potent CYP450 3A4 inhibitor, increased infigratinib peak plasma concentration (Cmax) and total systemic exposure (AUC) by 164% and 622%, respectively, and the AUC for the active metabolite, BHS697, by 174%. In general, the effect of grapefruit juice is concentration-, dose- and preparation-dependent, and can vary widely among brands. Certain preparations of grapefruit juice (e.g., high dose, double strength) have sometimes demonstrated potent inhibition of CYP450 3A4, while other preparations (e.g., low dose, single strength) have typically demonstrated moderate inhibition. Increased exposure to infigratinib and BHS697 may increase the incidence and severity of serious adverse reactions such as infections, anemia, pyrexia, abdominal pain, hypercalcemia, hyperphosphatemia, ocular toxicity (e.g., retinal pigment epithelial detachment), sepsis, stomatitis, diarrhea, palmar-plantar erythrodysesthesia syndrome, increased blood creatinine, increased lipase, and onycholysis.

MANAGEMENT: Infigratinib should be administered on an empty stomach at least one hour before or two hours after food. Patients should avoid consumption of grapefruit, grapefruit juice, or supplements that contain grapefruit during treatment with infigratinib.

GENERALLY AVOID: Alcohol may potentiate some of the pharmacologic effects of suvorexant. Use in combination may result in additive central nervous system depression and/or impairment of judgment, thinking, and psychomotor skills. In addition, alcohol may increase the risk of cognitive and complex behavioral changes associated with the use of hypnotics including suvorexant, such as amnesia, anxiety, hallucinations, sleep-driving, and other neuropsychiatric symptoms.

ADJUST DOSE: Grapefruit juice may significantly increase the plasma concentrations of suvorexant. The proposed mechanism is inhibition of CYP450 3A4-mediated first-pass metabolism in the gut wall by certain compounds present in grapefruit.

ADJUST DOSING INTERVAL: Administration with or soon after a meal may delay the gastrointestinal absorption of suvorexant. According to the product labeling, administration of suvorexant with a high-fat meal resulted in no meaningful change in peak plasma concentration (Cmax) or systemic exposure (AUC), but a delay in Tmax of approximately 1.5 hours.

MANAGEMENT: Concomitant use of suvorexant with alcohol should be avoided. Patients should be advised not to use suvorexant if they had alcohol that evening or before bed. Grapefruit juice should preferably be avoided; otherwise, the recommended dose of suvorexant is 5 mg when used with grapefruit juice and should not exceed 10 mg. Suvorexant may be taken with or without food; however, for faster sleep onset, suvorexant should not be administered with or soon after a meal.