Krystexxa contains the active ingredient pegloticase, a uric acid specific enzyme made from modified urate oxidase. It belongs to the class of PEGylated enzymes and is prepared as a sterile solution for intravenous infusion. The formulation includes sodium chloride and phosphates as key inactive ingredients. Krystexxa is designed for injection after dilution, commonly used for handling uric acid conditions.

How should I use this medication?

This medication is infused into a vein. It is given by your care team in a hospital or clinic setting.

A special MedGuide will be given to you before each treatment. Be sure to read this information carefully each time.

Talk to your care team about the use of this medication in children. Special care may be needed.

Overdosage: If you think you have taken too much of this medicine contact a poison control center or emergency room at once.

NOTE: This medicine is only for you. Do not share this medicine with others.

What if I miss a dose?

Keep appointments for follow-up doses. It is important not to miss your dose. Call your care team if you are not able to keep your appointment.

Where should I keep my medication?

This medication is given in a hospital or clinic. It will not be stored at home.

NOTE: This sheet is a summary. It may not cover all possible information. If you have questions about this medicine, talk to your doctor, pharmacist, or health care provider.

What side effects may I notice from receiving this medication?

Side effects that you should report to your care team as soon as possible:

• Allergic reactions—skin rash, itching, hives, swelling of the face, lips, tongue, or throat
• Gout—severe pain, redness, warmth, or swelling in joints, such as the big toe
• Headache, unusual weakness or fatigue, shortness of breath, nausea, vomiting, rapid heartbeat, blue skin or lips, which may be signs of methemoglobinemia
• Hemolytic anemia—unusual weakness or fatigue, dizziness, headache, trouble breathing, dark urine, yellowing skin or eyes
• Infusion reactions—chest pain, shortness of breath or trouble breathing, feeling faint or lightheaded

Side effects that usually do not require medical attention (report these to your care team if they continue or are bothersome):

• Fatigue
• Joint pain
• Nausea
• Vomiting

This list may not describe all possible side effects. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What should I tell my care team before I take this medication?

They need to know if you have any of these conditions:

• G6PD deficiency
• Heart disease
• High blood pressure
• An unusual or allergic reaction to pegloticase, other medications, foods, dyes, or preservatives
• Pregnant or trying to get pregnant
• Breastfeeding

What may interact with this medication?

• Methotrexate
• Other medications for gout, such as allopurinol, febuxostat, probenecid

This list may not describe all possible interactions. Give your health care provider a list of all the medicines, herbs, non-prescription drugs, or dietary supplements you use. Also tell them if you smoke, drink alcohol, or use illegal drugs. Some items may interact with your medicine.

What should I watch for while using this medication?

Your condition will be monitored carefully while you are receiving this medication. Tell your care team if your symptoms do not start to get better or if they get worse.

You may need blood work done while you are taking this medication.

This medication can cause serious allergic reactions. To reduce the risk, your care team may give you other medications to take before receiving this one. Follow the directions from your care team.

This medication may increase gout flares when you first start treatment. Do not stop taking this medication if you have a flare. Talk to your care team about how to reduce flares. They can help you find the option that works for you.

Your care team may test you for G6PD deficiency before you start this medication. When someone has low levels of the G6PD enzyme, their body breaks down red blood cells too fast. Red blood cells carry oxygen from the lungs to the rest of the body. This medication can cause serious side effects in people with G6PD deficiency. Talk to your care team right away if you have unusual weakness or fatigue, dizziness, headache, dark urine, or yellowing skin or eyes. Seek medical help if you have trouble breathing, a rapid heartbeat, or blue skin or lips.

What are the most serious risks of this medication?

This medication can cause serious and life-threatening allergic reactions. These reactions may occur with your first dose or at any time during treatment. Your care team will watch you closely. Tell your care team right away if you have a skin rash, itching, hives, swelling of the face, tongue, arms, or legs, trouble breathing, fast or irregular heartbeat, or feel faint or lightheaded.

This medicine should only be given by a healthcare provider who has special training and experience in using it.

People with G6PD deficiency should never get this medicine. This can cause severe, life-threatening bleeding. People of African or Mediterranean or South Asian descent are more likely to have G6PD deficiency and may need a genetic blood test to determine their risk.

This medication may cause a rare condition that affects how red blood cells carry oxygen from your lungs to the rest of your body (methemoglobinemia). Tell your care team right away if you have shortness of breath, a rapid heartbeat, or blue skin or lips.

This medicine should be given to you in the hospital, a clinic, or in a healthcare treatment setting.