Drug Interaction Report

Consumer information for this interaction is not currently available.

MONITOR: Coadministration with inhibitors of CYP450 2C9 may increase the plasma concentrations of lesinurad, which is primarily metabolized by the isoenzyme. According to the manufacturer, administration of lesinurad with the moderate CYP450 2C9 inhibitor fluconazole (200 mg daily) increased lesinurad peak plasma concentration (Cmax) and systemic exposure (AUC) by approximately 35% and 55%, respectively, compared to administration of lesinurad alone. In a cross-study pharmacogenomic analysis conducted in patients receiving single or multiple doses of lesinurad, patients who were deficient in CYP450 2C9 activity (i.e., CYP450 2C9 poor metabolizers) had an approximately 1.8-fold higher exposure to lesinurad at the 400 mg dose than extensive metabolizers.

MANAGEMENT: Caution is advised when lesinurad is prescribed with CYP450 2C9 inhibitors. Patients should be closely monitored for adverse renal effects such as serum creatinine elevations, renal function impairment, and nephrolithiasis. It may be advisable to avoid concomitant use with a potent CYP450 2C9 inhibitor such as gemfibrozil.

Consumer information for this interaction is not currently available.

MONITOR: Smoking and alcohol consumption during therapy with vadadustat may increase the risk of gastrointestinal erosions. Serious erosions, including gastrointestinal bleeding and the need for red blood cell transfusions, have been reported during vadadustat clinical trials. Patients with a history of gastrointestinal erosion, peptic ulcer disease, and current tobacco smokers and alcohol drinkers may be at higher risk of gastrointestinal injury.

MANAGEMENT: Caution is advised if vadadustat is prescribed to current tobacco smokers or alcohol drinkers. Patients should be advised to contact their physician if they develop potential signs and symptoms of gastrointestinal injury such as abdominal pain, hematemesis, trouble swallowing, chest or throat pain, and/or black, tarry stools.