This grade answers one narrow question: how strong is the public evidence and safety record behind this drug, and how clean is its money trail and court record? It is not a verdict on whether the drug is right for you.
WARNING: ANAPHYLAXIS and INFUSION REACTIONS, G6PD DEFICIENCY ASSOCIATED HEMOLYSIS and METHEMOGLOBINEMIA Anaphylaxis and infusion reactions have been reported to occur during and after administration of KRYSTEXXA. ( 5.1 , 5.2 ) Anaphylaxis may occur with any infusion, and generally manifests within 2 hours of the infusion. However, delayed hypersensitivity reactions have also been reported. ( 5.1 ) KRYSTEXXA should be administered in healthcare settings and by healthcare providers prepared to manage anaphylaxis and infusion reactions. ( 5.1 , 5.2 ) Premedicate with antihistamines and corticosteroids and closely monitor for anaphylaxis for an appropriate period of time after administration of KRYSTEXXA. ( 5.1 , 5.2 ) Monitor serum uric acid levels prior to each infusion and discontinue treatment if levels increase to above 6 mg/dL, particularly when 2 consecutive levels above 6 mg/dL are observed. ( 5.2 ) Screen patients at risk for G6PD deficiency prior to starting KRYSTEXXA. Hemolysis and methemoglobinemia have been reported with KRYSTEXXA in patients with G6PD deficiency. KRYSTEXXA is contraindicated in patients with G6PD deficiency. ( 4 , 5.3 ) WARNING: ANAPHYLAXIS and INFUSION R...
® (pegloticase) is indicated, for the treatment of chronic gout in adult patients refractory to conventional therapy. Gout refractory to conventional therapy occurs in patients who have failed to normalize serum uric acid and whose signs and symptoms are inadequately controlled with xanthine oxidase inhibitors at the maximum medically appropriate dose or for whom these drugs are contraindicated. KRYSTEXXA ® (pegloticase) is a PEGylated uric acid specific enzyme indicated for the treatment of chronic gout in adult patients refractory to conventional therapy. ( 1 ) Limitations of Use: KRYSTEXXA is not recommended for the treatment of asymptomatic hyperuricemia. ( 1 ) Limitations of Use: KRYSTEXXA is not recommended for the treatment of asymptomatic hyperuricemia.
is contraindicated in: Patients with glucose-6-phosphate dehydrogenase (G6PD) deficiency [see Warnings and Precautions (5.3) ]. Patients with history of serious hypersensitivity reactions, including anaphylaxis, to KRYSTEXXA or any of its components. Patients with glucose-6-phosphate dehydrogenase (G6PD) deficiency. ( 4 ) Patients with history of serious hypersensitivity reactions, including anaphylaxis, to KRYSTEXXA or any of its components. ( 4 )
Anaphylaxis : Anaphylaxis may occur with any KRYSTEXXA infusion. Pre-medicate and monitor patients. ( 5.1 ) Infusion Reactions : Infusion reactions occurred in patients treated with KRYSTEXXA. Pre-medicate and monitor patients. ( 5.2 ) G6PD Deficiency Associated Hemolysis and Methemoglobinemia : Screen patients at risk for G6PD deficiency. Do not administer KRYSTEXXA to patients with G6PD deficiency. ( 5.3 ) Gout Flares : Gout flare prophylaxis is recommended for at least the first 6 months of KRYSTEXXA therapy. ( 5.4 ) Congestive Heart Failure : Congestive heart failure exacerbation may occur. Monitor patients closely following infusion. ( 5.5 ) 5.1 Anaphylaxis In a 52-week controlled trial, which evaluated KRYSTEXXA co-administered with methotrexate compared to KRYSTEXXA alone, subjects were pre-treated with standardized infusion reaction prophylaxis and were discontinued from treatment with KRYSTEXXA if serum uric acid levels increased to above 6 mg/dL at 2 consecutive visits after the initiation of KRYSTEXXA therapy to reduce the risk of anaphylaxis. One subject randomized to the group treated with KRYSTEXXA co-administered with methotrexate (1%) experienced anaphylaxis during ...
The following serious adverse reactions are discussed in greater detail in other sections of the label: Anaphylaxis [see Warnings and Precautions (5.1) ] Infusion Reactions [see Warnings and Precautions (5.2) ] G6PD Deficiency Associated Hemolysis and Methemoglobinemia [see Warnings and Precautions (5.3) ] Gout Flares [see Warnings and Precautions (5.4) ] Congestive Heart Failure [see Warnings and Precautions (5.5) ] Co-administration with methotrexate: The most common adverse reactions (≥ 5% of patients) are gout flares, arthralgia, COVID-19, nausea and fatigue. ( 6.1 ) KRYSTEXXA alone: The most common adverse reactions (≥ 5% of patients) are gout flares, infusion reactions, nausea, contusion or ecchymosis, nasopharyngitis, constipation, chest pain, anaphylaxis and vomiting. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Amgen Inc. at 1-800-77-AMGEN (1-800-772-6436) or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch . 6.1 Clinical Trials Experience Because clinical studies are conducted under widely varying and controlled conditions, adverse reaction rates observed in clinical studies of a drug cannot be directly compared to rates in the clinical studies of another drug, and...
Dosage and Administration ( 2.1 , 2.3 ) 8/2025
Source: FDA SPL label for Krystexxa (Horizon Therapeutics USA, Inc.), effective 20260709. Full label on DailyMed.
These are counts of reports people filed, not rates of harm. Anyone can file one, and nobody checks whether the drug was the cause. Millions of doses are taken for every report sent, so the useful part is how this drug compares with the average across all drugs.
| 2019 | 2020 | 2021 | 2022 | 2023 | 2024 | 2025 | 2026 |
|---|---|---|---|---|---|---|---|
| 384 | 240 | 101 | 351 | 426 | 582 | 473 | 332 |
Source: the FDA's Adverse Event Reporting System (FAERS). Reports are voluntary and unverified. Drugs that are prescribed a lot, in the news, or in lawsuits attract more reports, so the percentages are compared with the whole database to correct for that partly, not fully.
Counts measure how much evidence exists and how transparent it is, not how big the benefit is. For that, ask your prescriber: if 100 people like me took this, how many would get better because of it, and how many would be harmed? (Doctors call these the "number needed to treat" and "number needed to harm.") It differs by condition and is the number drug ads leave out. Sources: PubMed, ClinicalTrials.gov.
In 2024, drug companies reported $5,301,725 in payments to US physicians and hospitals tied to this drug across 41,520 transactions (Krystexxa $5,301,725).
No pending federal MDL names this drug or its brands.
Not named in any federal pharmaceutical settlement of $100M or more on record.
Sources: CMS Open Payments (Sunshine Act); Judicial Panel on Multidistrict Litigation pending docket list; DOJ settlements as tabulated on Wikipedia with links to the primary record. State-court and individual suits are not included.
No same-class alternatives found in RxClass.