Pharmacokinetics, pharmacodynamics, and tolerability of verinurad, a selective uric acid reabsorption inhibitor, in healthy Japanese and non-Asian male subjects

Purpose: Verinurad (RDEA3170) is a selective uric acid reabsorption inhibitor in clinical development for treatment of gout and asymptomatic hyperuricemia. This study evaluated verinurad pharmacokinetics, pharmacodynamics, and tolerability in healthy Japanese and non-Asian adult male subjects. Methods: This was a Phase I, randomized, single-blind, placebo-controlled study. Panels of 8 Japanese subjects were randomized to receive oral verinurad (2.5-15 mg) or placebo administered as a single dose in a fasted and fed state and as once-daily doses for 7 days in a fed state. Eight non-Asian subjects received verinurad 10 mg as a single dose (fasted and fed) and multiple doses in the fed state. Serial plasma/serum and urine samples were assayed for verinurad and uric acid. Safety was assessed by adverse events and laboratory data. Results: Of 48 randomized subjects, 46 (Japanese, 39; non-Asian, 7) completed the study. Following single or multiple doses in Japanese subjects, maximum plasma concentration (C-max) and area under the plasma concentration-time curve (AUC) increased in a near dose-proportional manner. Time to C-max (T-max) was similar to 1.25-2.0 hours with fasting. A moderate-fat meal delayed T-max (range 3.0-5.0 hours) and had a variable effect on AUC (0%-97% increase) and C-max (0%-26% increase) across the dose groups. Following multiple verinurad 10 mg doses, C-max and AUC were 38% and 23% higher, respectively, in Japanese vs non-Asian subjects, largely due to body weight differences. Mean reduction of serum urate following multiple verinurad 10 mg doses was 46% and 44% after 24 hours in Japanese and non-Asian subjects, respectively. Verinurad was well tolerated at all doses. Conclusion: Verinurad monotherapy lowered serum urate and was well tolerated in both healthy Japanese and non-Asian males, while small differences in plasma pharmacokinetics were observed. These data support further evaluation of once-daily verinurad as a treatment for gout and asymptomatic hyperuricemia.