Background/Purpose: Pegloticase, a recombinant pegylated uricase, rapidly reduces serum urate (SU) in patients refractory to/intolerant of oral urate-lowering therapies (ULTs).^1,2 However, pegloticase is generally used for ≤1 year for intensive SU-lowering and subsequent urate burden depletion. Optimal post-pegloticase treatment has not yet been established, but use and efficacy of oral ULTs remains an important unanswered clinical question. This analysis retrospectively examined data from a large US rheumatology database to better understand real-world practice patterns of post-pegloticase oral ULT use and to preliminarily examine post-pegloticase oral ULT efficacy.

Methods: Patients in the UR-NICE data repository who had first pegloticase infusion code (J2507) between 2012 and 2022 were included in analyses. The beginning and end of therapy was defined as the date of first and last pegloticase infusion code, respectively. All patients were in the database for ≥60 days following last infusion. Oral ULT use (allopurinol, febuxostat, probenecid) before and after pegloticase therapy was examined. Patients were also stratified by those that did and did not receive ≥12 infusions (considered as “full course” in prior retrospective studies³). Patient characteristics prior to pegloticase therapy were also examined to help characterize the pegloticase-treated population.

Results: 211 patients (77% male; mean[±SD] age: 62.7±12.8 years, BMI: 32.9±7.2 kg/m², eGFR: 66.0±24.7 ml/min/1.73m² [46% eGFR < 60]) were included. 74% had tophaceous gout and pre-pegloticase SU was 7.9±2.5 mg/dL (n=148). Available inflammatory biomarkers were moderately elevated (median CRP: 3.3 mg/dL [n=114], neutrophil-to-lymphocyte ratio [NLR]⁴: 2.9 [n=41]). 141 patients (67%) had pre-pegloticase oral ULT use noted (73% allopurinol, 48% febuxostat, and/or 18% probenecid). Patients received a mean (±SD) of 12.3±12.6 pegloticase infusions (median: 9; 88 [42%] received ≥12), with a 2.2±2.0 wk dosing interval. Following last infusion, 115 patients (55%) began oral ULT (67% allopurinol, 44% febuxostat, and/or 17% probenecid), most (67%) within 30 days of last pegloticase infusion. More patients who received ≥12 infusions had an SU < 6 mg/dL when treated with post-pegloticase oral ULT than those who received < 12 infusions (first post-ULT SU < 6 mg/dL: 78% vs 36%; mean SU: 4.7±3.0 [n=37] vs 7.4±2.9 mg/dL [n=47]).

Conclusion: These pegloticase-treated patients reflected a typical uncontrolled gout population. Two-thirds of patients began oral ULT after pegloticase, most within 30 days of last infusion. Patients who had a longer pegloticase course (≥12 infusions) were more likely to have post-treatment oral ULT efficacy, perhaps because of greater urate burden depletion. These data suggest oral ULTs may be effective after successful pegloticase therapy but further prospective studies are needed to verify our findings and better understand how overall urate burden may influence oral ULT efficacy.

References
1. Sundy JS, et al. JAMA 2011;306:711-20.
2. Botson JK, et al. Arthritis Rheumatol 2023;75:293-304.
3. Keenan RT, et al. Semin Arthritis Rheum 2021;51:347-52.
4. Forget P, et al. BMC Res Notes 2017;10:12.

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ACR Meeting Abstracts - https://acrabstracts.org/abstract/oral-urate-lowering-therapy-use-and-efficacy-following-pegloticase-treatment-findings-from-a-rheumatology-network-database/