Drug Interaction Report

MONITOR: Coadministration with inhibitors of organic anion transporting polypeptides (OATP) 1B1 and/or 1B3 may increase the plasma concentrations and effects of momelotinib, which is a substrate of these hepatic uptake transporters. In a phase I study, coadministration of momelotinib (200 mg) with a single dose of the OATP1B1/1B3 inhibitor rifampin (600 mg) increased the peak plasma concentration (Cmax) and systemic exposure (AUC) of momelotinib by 40% and 57%, respectively. The Cmax and AUC of the active metabolite of momelotinib, M21, was also increased, by 6% and 12%, respectively.

MANAGEMENT: Caution is advised if momelotinib is used in combination with inhibitors of OATP1B1 and/or 1B3. Dosage adjustments of momelotinib may be required. Patients should be advised to report any momelotinib-related adverse reactions such as bacterial or viral infection, thrombocytopenia, neutropenia, hepatotoxicity, thrombosis, and adverse cardiovascular events.

MONITOR: Coadministration with inhibitors of organic anion transporting polypeptides (OATP) 1B1 and/or 1B3 may increase the plasma concentrations and effects of momelotinib, which is a substrate of these hepatic uptake transporters. In a phase I study, coadministration of momelotinib (200 mg) with a single dose of the OATP1B1/1B3 inhibitor rifampin (600 mg) increased the peak plasma concentration (Cmax) and systemic exposure (AUC) of momelotinib by 40% and 57%, respectively. The Cmax and AUC of the active metabolite of momelotinib, M21, was also increased, by 6% and 12%, respectively.

MANAGEMENT: Caution is advised if momelotinib is used in combination with inhibitors of OATP1B1 and/or 1B3. Dosage adjustments of momelotinib may be required. Patients should be advised to report any momelotinib-related adverse reactions such as bacterial or viral infection, thrombocytopenia, neutropenia, hepatotoxicity, thrombosis, and adverse cardiovascular events.

ADJUST DOSING INTERVAL: Administration of atazanavir with food enhances oral bioavailability and reduces pharmacokinetic variability. According to the manufacturer, administration with a light meal increased the peak plasma concentration (Cmax) and area under the concentration-time curve (AUC) of a single 400 mg dose of atazanavir by 57% and 70%, respectively, relative to the fasting state. Administration with a high-fat meal resulted in a mean increase of 35% in atazanavir AUC and no change in Cmax compared to fasting. The coefficient of variation of AUC and Cmax decreased by approximately one-half when given with either a light or high-fat meal compared to the fasting state.

MANAGEMENT: To ensure maximal oral absorption, atazanavir should be administered with or immediately after a meal.