Abstract
Elevated serum uric acid is a cardiovascular risk factor in patients with hypertension, even when blood pressure (BP) is well controlled. Xanthine oxidoreductase inhibitors (XORi) reduce serum uric acid levels and have several other potential effects. This multicenter, randomized, open-label study compared the effects of two XORi, topiroxostat and febuxostat, on arterial stiffness, uric acid levels, and BP in hypertensive patients with hyperuricemia. Patients received topiroxostat 40-160 mg/day or febuxostat 10-60 mg/day, titrated to maintain serum uric acid <6 mg/dl, for 24 weeks. The primary endpoint was change in the cardio-ankle vascular index (CAVI) from baseline to 24 weeks. There were no significant changes in CAVI from baseline to 24 weeks (from 9.13 to 9.16 [feboxustat] and 8.98 to 9.01 [topiroxostat]). Compared with baseline, there were significant reductions in serum uric acid (-2.9 and -2.5 mg/dl; both p < 0.001) and morning home systolic BP (-3.6 and -5.1 mm Hg; both p < 0.01) after 24 weeks' treatment with febuxostat and topiroxostat. BP decreased to the greatest extent in the subgroup of patients with uncontrolled blood pressure at baseline. Topiroxostat, but not febuxostat, significantly decreased plasma xanthine oxidoreductase activity versus baseline. The urinary albumin-creatinine ratio (UACR) decreased significantly from baseline to 24 weeks with topiroxostat (-20.8%; p = 0.021), but not febuxostat (-8.8%; p = 0.362). In conclusion, neither topiroxostat nor febuxostat had any significant effects on arterial stiffness over 24 weeks' treatment.