Comparison of the incidence of proteinuria and changes in eGFR among febuxostat and topiroxostat users.

Abstract

Background: Febuxostat and topiroxostat are non-purine selective xanthine oxidoreductase inhibitors commonly used for hyperuricaemia treatment in Japan. However, comparative data on the effects of febuxostat and topiroxostat on renal function and proteinuria are limited. This study compared proteinuria incidence and changes in the estimated glomerular filtration rate (eGFR) among prevalent febuxostat and topiroxostat users.

Methods: We conducted a retrospective cohort study using databases provided by DeSC Healthcare, Inc. (Tokyo, Japan). We identified 17,446 individuals (11.8% women; mean age 67.4 years) with eGFR ≥ 30 mL/min/1.73 m² and no history of cardiovascular disease or proteinuria at baseline. Separate analyses were performed for individuals with eGFR < 60 mL/min/1.73 m² and those with eGFR ≥ 60 mL/min/1.73 m². The adjusted hazard ratio (HR) for proteinuria incidence in topiroxostat users compared with febuxostat users was assessed using the Cox model. Changes in eGFR were compared between the two groups using multiple regression analysis.

Results: During the mean follow-up period of 1.79 years, 1,433 participants developed proteinuria. In non-diabetic individuals with eGFR ≥ 60 mL/min/1.73 m², the adjusted HR for proteinuria incidence in topiroxostat users compared with febuxostat users was 0.60 (95% confidence interval, 0.40-0.91; p = 0.016). No significant differences were observed in eGFR changes between the two groups with eGFR < 60 and ≥ 60 mL/min/1.73 m².

Conclusion: Topiroxostat prevalent users had a lower risk of proteinuria than febuxostat prevalent users in non-diabetic individuals with eGFR ≥ 60 mL/min/1.73 m². Our findings suggest that topiroxostat might be more effective than febuxostat in preventing proteinuria in non-diabetic individuals with eGFR ≥ 60 mL/min/1.73 m².