Potency on lowering serum uric acid in gout patients: a pooled analysis of registrative studies comparing febuxostat vs. allopurinol.

OBJECTIVE

Hyperuricemia leading to urate crystal formation in tissues represents the pathophysiological mechanism of gout. Guidelines recommend a therapeutic target of serum urate concentration (sUA) <6 mg/dL, or even lower (≤5 mg/dL) in patients with large deposits. We conducted an analysis with the aim to achieve additional insights into the urate-lowering efficacy of two xanthine oxidase inhibitors, allopurinol and febuxostat.

PATIENTS AND METHODS

This was a pooled analysis of phase III trials on allopurinol and febuxostat, including 4101 patients with gout and hyperuricemia. The efficacy outcomes were: mean reduction of sUA concentration from baseline; number of patients with target sUA levels (<6.0 mg/dL or ≤5 mgdL); time to reach target sUA levels.

RESULTS

Three registrative, phase III, randomized, multicenter, placebo-controlled/allopurinol-controlled trials assessing the efficacy of febuxostat, were included. The mean reduction of sUA concentration with any dose of febuxostat was higher (-2.92±2.87 mg/dL; -27%), with respect to placebo- (-0.62±1.84 mg/dL; -5%) and allopurinol-pooled groups (-2.41±2.20 mg/dL; -24%). Moreover, febuxostat showed a higher probability to achieve the recommended target sUA concentration than allopurinol [odds ratio: 2.43 (95% CI: 2.119-2.789) and 4.05 (95% CI: 3.41-4.82) for sUA levels <6 mg/dL and ≤5 mg/dL, respectively]. Patients on any-dose febuxostat reached target sUA faster than allopurinol-treated patients (86.04±71.47 vs. 98.76±70.88 days and 52.08±49.97 vs. 90.42±68.03 days for reaching sUA levels <6 mg/dL and ≤5 mg/dL, respectively; p <0.001 for both comparisons).

CONCLUSIONS

In patients with gout and hyperuricemia, febuxostat was significantly more effective and faster than allopurinol in obtaining the recommended target sUA levels, which were reached by a higher number of patients. Therefore, febuxostat was confirmed as an effective option for the treatment of hyperuricemia in gout.