Prospective randomized comparison of effect on coronary endothelial and renal function between febuxostat and benzbromarone in hyperuricemic patients with coronary artery disease: EFEF study.

Background and Aims: There are two types of serum uric acid-lowering agents, the xanthine oxidoreductase (XO) inhibitor and non-XO inhibitor. We investigated whether febuxostat, XO inhibitor, could produce more favorable effects on coronary endothelial function (CEF) and renal function than benzbromarone, non-XO inhibitor, in hyperuricemic coronary artery disease (CAD) patients. Methods: We divided 21 hyperuricemic patients with stenting for left anterior descending (LAD) or left circumflex (LCX) artery into patients started on febuxostat (F group) and those on benzbromarone (B group). After 8 months, all patients underwent CEF evaluations (acetylcholine provocation test) and optical coherence tomography (OCT) for non-culprit vessels (e.g. if patients received LAD stenting, we evaluated LCX). We compared the diameter ratio induced by acetylcholine and baseline (CEF ratio), thin-cap fibroatheroma and calcified plaque by OCT, uric acid, oxidative stress biomarkers, and renal function including estimated glomerular filtration rate (eGFR) between F and B groups. Creatinine 2 days after stenting was measured to evaluate contrast-induced nephropathy (CIN). Results: Change of eGFR was significantly lower in F group (n= 11) than B group over 8 months while the other parameters including CEF ratio were similar. F group showed favorable effects for CIN. Conclusion: In conclusion, 8-months of febuxostat, XO inhibitor, does not significantly protect CEF but can protect the renal function including CIN in hyperuricemic patients with CAD compared to benzbromarone, non-XO inhibitor.