Pegloticase (Krystexxa)

medicine injections

Pegloticase is a protein that is designed to treat severe chronic gout when other more common treatments have failed or are not tolerated.  More specifically, the protein is an enzyme (a substance that results in an action) that breaks down uric acid into a substance that the body can excrete.

How to Take It

Pegloticase is given as an infusion, through a needle inserted into one of the veins by a health care professional. The infusion lasts at least two hours and is given every two weeks. It is used in combination with another drug to prevent gout flares during treatment with pegloticase.

Prior to receiving the first infusion, your doctor should check for a condition known as G6PD deficiency because pegloticase is not safe if this is present.

Prior to receiving each infusion, it is very important to check uric acid levels. If the uric acid levels are measured above 6 mg/dL despite pegloticase infusions, it could indicate that antibodies have developed against the pegloticase, an event that eventually occurs in nearly all patients receiving pegloticase. This development can result in loss of effectiveness of pegloticase and can predict the onset of a future infusion reaction.

Side Effects

Pegloticase often causes certain side effects. The most common side effect is a gout attack, which is why a medication to prevent a gout attack should always be given while receiving pegloticase.

As mentioned above, uric acid is checked before each infusion because if >6 mg/dL, this could indicate the development of an antibody to pegloticase, which itself can predict a future infusion reaction.

The most severe infusion reaction can be anaphylaxis, or a very severe allergic reaction, that could result in serious harm or death if not identified and treated quickly. Immediately tell your health care professional if you develop shortness of breath, wheezing, other unusual breathing sounds, lightheadedness, chest pain, or swelling inside the mouth.

Other side effects reported include nausea, itching, redness, bruising, constipation, and vomiting.

Tell Your Doctor

Before taking pegloticase, tell your doctor if you plan to become pregnant. Studies of pegloticase on pregnancy in animals have shown some dangers in pregnancy, but it is unclear if it is dangerous in humans.

Before taking pegloticase, tell your doctor if you have G6PD deficiency or family history of this. If G6PD deficiency is present, pegloticase is not safe.

Before taking pegloticase, tell your doctor if there is any reason why you may not be able to receive the pegloticase at the recommended two week intervals for the foreseeable future. Since antibodies eventually form in nearly all patients receiving pegloticase, it is important to commit to an every two week infusion so that the medicine can be most effective.

During infusions, immediately tell your health care professional if you develop shortness of breath, wheezing, other unusual breathing sounds, lightheadedness, chest pain, or swelling inside the mouth. This could indicate anaphylaxis, a potentially dangerous or deadly reaction to pegloticase.

Written June 2018 by Chase Correia, MD and reviewed by the American College of Rheumatology Committee on Communications and Marketing.

This information is provided for general education only. Individuals should consult a qualified health care provider for professional medical advice, diagnosis and treatment of a medical or health condition.