To systematically review the evidence on the efficacy, safety, and cost-effectiveness of urate-lowering therapy for gout: xanthine oxidase inhibitors (allopurinol and febuxostat), uricosuric medications (benzbromarone, probenecid and sulfinpyrazone), and uricases (pegloticase and rasburicase).
A systematic review was performed as part of the 3e (Evidence, Expertise, Exchange) Initiative on Gout. The primary efficacy outcomes were frequency of acute gout attacks, study participant withdrawal due to adverse events, and cost-effectiveness. Serum urate-lowering was a secondary outcome and was the most commonly reported outcome in the included trials.
The search identified 17 articles for efficacy, 31 for safety, and 3 for cost-effectiveness. The main outcome described in these studies was serum urate-lowering. Allopurinol, febuxostat, and pegloticase are all effective at lowering serum urate compared to placebo and febuxostat (≥ 80 mg) was more effective at lowering serum urate than allopurinol. Compared to probenecid, benzbromarone was more effective at lowering serum urate. Regarding acute gout attacks, pegloticase and febuxostat (≥ 120 mg) resulted in more acute attacks than placebo. Regarding the primary safety outcome, more withdrawals due to adverse events were seen only when pegloticase was compared to placebo. The two trials of cost-effectiveness were inconclusive.
There is currently moderate quality data supporting the efficacy and safety of allopurinol, febuxostat, benzbromarone, and probenecid in gout. Pegloticase, while efficacious, is associated with more withdrawals due to adverse events and infusion reactions. There is insufficient evidence currently with respect to the cost-effectiveness or the most optimal sequencing of urate-lowering therapy.