medwireNews: Results of a phase III trial indicate that both the immediate and extended release formulations of febuxostat reduce serum uric acid (sUA) levels in patients with gout, including those with impaired renal function.
These findings are in accordance with recent phase II trial results, and suggest that febuxostat “has the potential to help address the treatment of gout in patients with renal impairment,” say Kenneth Saag (University of Alabama at Birmingham, USA) and co-investigators.
As reported in Arthritis & Rheumatology, 1790 patients with gout who had either normal kidney function (estimated glomerular filtration rate [eGFR] ≥90 mL/min per 1.73 m2) or mild-to-severe renal impairment (eGFR=15–89 mL/min per 1.73 m2) were randomly assigned to receive febuxostat immediate release (IR) or extended release (XR) at a dose of 40 mg or 80 mg once daily, or to receive placebo, for a total of 3 months.
Patients receiving febuxostat IR or XR at either dose were significantly more likely to achieve target sUA levels below 5.0 mg/dL at 3 months than those given placebo, with rates of 15.7–50.1% versus 0.3%.
Saag et al report that in general, “[e]quivalent doses of febuxostat XR and IR had similar treatment effects on sUA endpoints,” but a significantly higher proportion of patients receiving the XR versus the IR formulation at a dose of 40 mg achieved sUA levels below 5.0 mg/dL (25.9 vs 15.7%).
Of note, the team found that both formulations of febuxostat, at both doses, were associated with a significantly greater proportion of patients meeting target sUA levels versus placebo among patients in all subgroups for renal function (normal function and mild, moderate, or severe impairment), with the exception of the XR formulation at the 40 mg dose.
Overall rates of treatment-emergent adverse events (TEAEs) were “low and evenly distributed between treatment arms,” and similar across renal function subgroups, say the researchers. In all, TEAEs were reported in 37.6–41.5% of patients, most commonly diarrhea, nasopharyngitis, and hypertension, and 1.7–3.4% experienced serious TEAEs.
Three patients died during the study. One death, caused by cardiorespiratory arrest in a patient with severe renal impairment in the febuxostat IR 80 mg group, was considered to be treatment-related.
Together, these results suggest that febuxostat is overall “well tolerated and effective in patients with gout and normal renal function or mild-to-severe renal impairment,” write Saag and team. They note, however, that febuxostat did not reduce the risk for gout flare relative to placebo; flare rates were comparable across the groups at 20.7–27.2%.
medwireNews is an independent medical news service provided by Springer Healthcare. © 2018 Springer Healthcare part of the Springer Nature group