Drug Interaction Report

CONTRAINDICATED: Coadministration with inhibitors of CYP450 1A2 may significantly increase the plasma concentrations of fezolinetant, which is primarily metabolized by the isoenzyme. In clinical drug interaction studies, coadministration of the potent CYP450 1A2 inhibitor fluvoxamine increased the peak plasma concentration (Cmax) and systemic exposure (AUC) by 80% and 840%, respectively. Likewise, the moderate CYP450 1A2 inhibitor, mexiletine, is predicted through physiologically based pharmacokinetic (PBPK) modeling to increase the Cmax and AUC of fezolinetant by 40% and 360%, respectively. The weak CYP450 1A2 inhibitor cimetidine is also predicted via PBPK to increase the Cmax and AUC of fezolinetant by 30% and 100%, respectively.

MANAGEMENT: Concomitant use of fezolinetant with CYP450 1A2 inhibitors is considered contraindicated.

CONTRAINDICATED: Coadministration with inhibitors of CYP450 1A2 such as caffeine may significantly increase the plasma concentrations of fezolinetant, which is primarily metabolized by the isoenzyme. The interaction has not been studied with caffeine but has been reported for other CYP450 1A2 inhibitors. Consumption of caffeine-containing food or beverages (e.g., chocolate, coffee, cola drinks, energy drinks, tea) could result in an interaction with fezolinetant. In clinical drug interaction studies, coadministration of the potent CYP450 1A2 inhibitor fluvoxamine increased the peak plasma concentration (Cmax) and systemic exposure (AUC) by 80% and 840%, respectively. Likewise, the moderate CYP450 1A2 inhibitor, mexiletine, is predicted through physiologically based pharmacokinetic (PBPK) modeling to increase the Cmax and AUC of fezolinetant by 40% and 360%, respectively. The weak CYP450 1A2 inhibitor cimetidine is also predicted via PBPK to increase the Cmax and AUC of fezolinetant by 30% and 100%, respectively.

MANAGEMENT: Concomitant use of fezolinetant with CYP450 1A2 inhibitors such as caffeine, including caffeine-containing food or beverages, is considered contraindicated.

GENERALLY AVOID: The ingestion of foods containing photosensitizing components (e.g., limes, figs, parsley, parsnips, rue (Ruta graveolens), mustard, carrots and celery) may increase the risk of photosensitivity and severe burning during methoxsalen therapy. Two cases of photosensitivity involving rue and a soup containing celery, parsley, and parsnip have been reported in PUVA patients.

MANAGEMENT: Patients who are undergoing PUVA treatment and taking methoxsalen should be advised to avoid eating large quantities of these foods.