Treating Gout in Kidney Transplant Recipients on Immunosuppression

Immunomodulator cotherapy has been shown to improve the efficacy of pegloticase by reducing its immunogenicity. Results of the PROTECT study, an open-label, single-arm study in kidney transplant recipients on stable immunosuppressants with uncontrolled gout suggested that pegloticase was effective in reducing serum urate levels, with a high responder rate of 89% (serum urate <6 mg/dL for ≥80% of the time during month 6, while preserving key indicators of graft function).

Abdul A. Abdellatif, MD, and colleagues conducted a study to assess the pharmacokinetics and immunogenicity of pegloticase in patients with uncontrolled gout with a history of kidney transplant on immunosuppression. Results were reported during a poster session at the American Society of Nephrology Kidney Week 2022 in a poster titled Pharmacokinetics and Immunogenicity of Pegloticase in Patients With Kidney Transplants Revoicing Pegloticase for Uncontrolled Gout.

Pegloticase was administered via intravenous (IV) infusion 8 mg every 2 weeks for 24 weeks. Pharmacokinetics and immunogenicity analyses were conducted using serum samples collected pre- and postdose at multiple visits.

The analysis included 20 patients who received at least one dose of pegloticase. Among serum urate responders, measurable pegloticase concentrations were maintained through month 6. Following initiation of pegloticase treatment, median pre- and postdose pegloticase concentration ranged from 0.97 to 1.59 µg/mL and 1.57 to 3.60 µg/mL, respectively. Conversely, the two nonresponders both had predose concentrations of pegloticase below the limit of quantification (BLQ), and one had a BLQ value postinfusion, consistent with the immunogenicity results.

Pegloticase exposures were higher in patients observed with pegloticase monotherapy, consistent with previously observed improved pharmacokinetic seen with methotrexate cotherapy. There were no reactions or anaphylaxis during the trial period.

“Pegloticase 8 mg IV every 2 weeks with standard of care immunosuppressants in transplant patients resulted in a high serum urate responder rate and improved pegloticase exposure,” the researchers said.

Source: Abdellatif AA, Xin Y, Chamberlain J, et al. Pharmacokinetics and immunogenicity of pegloticase in patients with kidney transplants receiving pegloticase for uncontrolled gout. FR-PO232. Abstract of a poster presented at the American Society of Nephrology Kidney Week 2022; November 4, 2022; Orlando, Florida.