In patients with chronic refractory gout whose serum urate (SU) was not maintained at 6 mg/dL or less, adding an additional tolerizing dose of pegloticase between the first and second biweekly administrations showed an overall response rate of 44%, according to results from a trial presented at the American College of Rheumatology Convergence 2021. Background urate-lowering therapy was discontinued for participants, who were treated with three weekly doses of 8 mg pegloticase followed by biweekly administration of 8 mg pegloticase for a total of 10 doses in 17 weeks. Continued dosing was only permitted if the SU was 6 mg/dL or less. Standard infusion prophylaxis and gout flare prophylaxis were required. Responders had significantly higher trough levels of pegloticase than nonresponders 1 week after the initial infusion that persisted throughout the trial. Among patients with trough pegloticase levels greater than 1.22 mg/mL at 1 week, 73.7% were responders to treatment, whereas 31.6% with trough levels less than or equal to 1.22 mg/mL at 1 week were responders.