The primary objective of this study is to evaluate the effect of pegloticase on the response rate of sustained serum uric acid (sUA) reduction to sUA < 6 mg/dL during Month 6 of treatment.

The study design includes: 1) a Screening Period, lasting up to 35 days; 2) a 24-week treatment period which includes an End-of-Study (Week 24) /Early Termination Visit; 3) a safety follow-up phone/email Visit 30 days after the last infusion; and 4) a 3 month post-treatment follow up visit.

Study acquired from Horizon in 2024.

Inclusion Criteria:

• Willing and able to give informed consent;

• Willing and able to comply with the prescribed treatment protocol and evaluations for the duration of the study;

• Adult men or women ≥ 18 years of age;

• Is a recipient of a de novo kidney from a living or deceased donor and is >1 year post transplant prior to screening;

• Is on a stable standard of care immunosuppression therapy for at least 3 months prior to screening;

• Kidney allograft is functional at entry, based on an estimated glomerular filtration rate (eGFR) ≥ 15 mL/min/1.73m²;

• Women of childbearing potential have a negative screening serum pregnancy test and will be required to use a medically approved form of birth control during their participation in the study;

• Uncontrolled gout, defined as:

  1. Hyperuricemia during screening as documented by sUA ≥ 7 mg/dL during Screening and prior to entry into the Treatment Period (Note: the sUA may be repeated up to 3 times during the Screening Period to confirm eligibility), and
  2. Inability to maintain sUA <6 mg/dL on other urate-lowering therapy or intolerable side effects or contraindicated with conventional urate-lowering therapy, and
  3. At least 1 of the following:

  i. Evidence of tophaceous deposits; ii. Recurrent gout flares defined as 2 or more flares in the 12 months prior to Screening; iii. Presence of chronic gouty arthritis;

• Able to tolerate low-dose prednisone (< 10 mg/day) as part of the required standard gout flare prophylaxis regimen for ≥ 1 week before the first infusion.

Exclusion Criteria:

• Any other organ transplant beside kidney;
• Any severe infection, unless treated and completely resolved at least 2 weeks prior to Day 1;
• Chronic or active hepatitis B virus infection;
• Known history of hepatitis C virus ribonucleic acid (RNA) positivity unless treated and viral load is negative;
• Known history of human immunodeficiency virus (HIV) positivity;
• Glucose-6-phosphate dehydrogenase (G6PD) deficiency (tested at the Screening Visit);
• Decompensated congestive heart failure or hospitalization for congestive heart failure within 3 months of the Screening Visit, uncontrolled arrhythmia, treatment for acute coronary syndrome (myocardial infarction or unstable angina), or uncontrolled blood pressure (> 160/100 mm Hg) at the end of the Screening Period (Day 1 prior to infusion);
• Pregnant, planning to become pregnant, breastfeeding, planning to impregnate female partner, or not using an effective form of birth control, as determined by the Investigator;
• Prior treatment with pegloticase, another recombinant uricase (rasburicase), or concomitant therapy with a polyethylene glycol-conjugated drug;
• Known allergy to pegylated products or history of anaphylactic reaction to a recombinant protein or porcine product;
• Receipt of an investigational drug within 4 weeks or 5 half-lives, whichever is longer, prior to Day 1, or plans to take an investigational drug during the study;
• Currently receiving systemic or radiologic treatment for ongoing cancer;
• History of malignancy within 5 years other than non-melanoma skin cancer, in situ carcinoma of cervix, early stage renal cell cancer or early stage prostate cancer that has been completely resected > 2 years prior to screening;
• Uncontrolled hyperglycemia with a plasma glucose value > 240 mg/dL at Screening that is not subsequently controlled by the end of the Screening Period;
• Diagnosis of osteomyelitis;
• Known history of hypoxanthine-guanine phosphoribosyl-transferase deficiency, such as Lesch-Nyhan and Kelley-Seegmiller syndrome;
• Unsuitable candidate for the study, based on the opinion of the Investigator (e.g., cognitive impairment), such that participation might create undue risk to the subject or interfere with the subject's ability to comply with the protocol requirements or complete the study;
• Currently receiving allopurinol, febuxostat or other urate lowering medications and unable to discontinue medication 7 days prior to Day 1; or
• Currently receiving probenecid and unable to discontinue medication within 3 days, prior to Day 1.

De-identified individual patient data for variables necessary to address the specific research question in an approved data sharing request.

Data sharing requests relating to this study will be considered beginning 18 months after the study has ended and either 1) the product and indication (or other new use) have been granted marketing authorization in both the US and Europe or 2) clinical development for the product and/or indication discontinues and the data will not be submitted to regulatory authorities. There is no end date for eligibility to submit a data sharing request for this study.

Qualified researchers may submit a request containing the research objectives, the Amgen product(s) and Amgen study/studies in scope, endpoints/outcomes of interest statistical analysis plan, data requirements, publication plan, and qualifications of the researcher(s). In general, Amgen does not grant external requests for individual patient data for the purpose of re-evaluating safety and efficacy issues already addressed in the product labelling. Requests are reviewed by a committee of internal advisors, and if not approved, may be further arbitrated by a Data Sharing Independent Review Panel. Upon approval, information necessary to address the research question will be provided under the terms of a data sharing agreement. This may include anonymized individual patient data and/or available supporting documents, containing fragments of analysis code where provided in analysis specifications. Further details are available at the URL below.

From the date of first dose of treatment through 30 days after the last dose of treatment (up to Week 22 plus 30 days).