Effectivity and Safety of Febuxostat in Reducing Serum Urate in Gout Patients With Chronic Kidney Disease: A Prospective Multicenter ULTRA Registry Study.

Abstract

Gout, an inflammatory arthritis caused by hyperuricemia, is highly prevalent with chronic kidney disease (CKD). We evaluated longitudinal changes in serum urate (SU) levels and febuxostat dosage according to renal function. Among 405 patients in the Urate-Lowering Therapy in Gout (ULTRA) registry between November 2021 and December 2023, 112 were analyzed after excluding those with < 1-year follow-up period, nonfebuxostat therapy, or missing data. SU levels and febuxostat doses were compared between the 2 groups at baseline, 6, and 12 months. Baseline SU levels did not differ between the normal and CKD groups. After febuxostat therapy, mean (SD) SU levels were significantly lower in the CKD group than in the normal group (at 6 months: 4.45 [1.84] mg/dL vs 5.62 [1.62] mg/dL, <i>P</i> = 0.001; at 12 months: 4.81 [1.81] mg/dL vs 5.60 [1.94] mg/dL, <i>P</i> = 0.04). Meanwhile, the mean dosages of febuxostat were lower in CKD group than in the normal group (at 6 months: 40.61 [22.07] mg vs 47.54 [19.43] mg, <i>P</i> = 0.11; at 12 months: 40.59 [21.73] mg vs 48.49 [19.70] mg, <i>P</i> = 0.06), although these differences were not statistically significant. Additionally, the proportion of patients achieving SU < 6 mg/dL at 6 months was higher in the CKD group than in the normal group (91.2% vs 68.6%, <i>P</i> = 0.01). An individualized dosing strategy based on SU response, rather than renal function alone, may optimize treatment outcomes in these patients.