Effect of Dotinurad on Serum Uric Acid Concentration in Chronic Kidney Disease Patients Treated with Febuxostat.

Background: Febuxostat is recommended for treatment of severe hyperuricemia in chronic kidney disease (CKD). We previously reported a significant positive correlation between fractional excretion of uric acid (FEUA) and estimated excretion of uric acid (eEUA) in patients receiving febuxostat and proposed that the addition of uricosuric agents could further decrease serum uric acid (sUA) levels by enhancing FEUA and eEUA in patients treated with febuxostat.

Methods: This retrospective study included 34 patients with CKD who were categorized into three groups (G3-G5) according to their estimated glomerular filtration rate (eGFR). The effects on sUA, FEUA, and eEUA of adding dotinurad (0.5 mg/day) to febuxostat (10 mg/day) were evaluated in these patients. Specifically, we examined changes in sUA, FEUA, and eEUA in each group after the addition of dotinurad.

Results: Dotinurad significantly increased FEUA in all groups and notably decreased sUA in groups G3 and G4 but not in group G5. There was no significant change in eEUA in any group. Dotinurad maintained the significant positive correlation between FEUA and eEUA in patients receiving febuxostat.

Conclusions: This study is the first to show the effect of combining dotinurad with febuxostat in lowering sUA levels in G3 and G4 patients. Additional research is required in order to clarify the pharmacological mechanisms of dotinurad in patients with CKD.