Possible side effects of KRYSTEXXA include:
- Anaphylaxis which occurred in some patients treated with KRYSTEXXA. KRYSTEXXA should be administered in healthcare settings and by healthcare providers prepared to manage anaphylaxis. Patients should be pre-medicated with antihistamines and corticosteroids. Patients should be closely monitored for an appropriate period of time for anaphylaxis after administration of KRYSTEXXA.
- Infusion reactions which occurred in some patients treated with KRYSTEXXA. The risk of an infusion reaction is higher in patients who have lost therapeutic response. Because the risk of infusion reactions is higher in patients who lose therapeutic response to KRYSTEXXA, monitor serum uric acid before each infusion and consider discontinuing treatment if levels rise above 6mg/dL, particularly when two consecutive levels above 6 mg/dL are observed.
- As with other urate-lowering therapies, an increase in gout flares was seen in some patients treated with KRYSTEXXA. Gout flare prophylaxis with a non-steroidal anti-inflammatory drug (NSAID) or colchicine is recommended starting at least 1 week before initiation of KRYSTEXXA therapy and lasting at least 6 months, unless medically contraindicated or not tolerated.
KRYSTEXXA has not been formally studied in patients with congestive heart failure, but some patients in clinical trials experienced exacerbation. Exercise caution when using KRYSTEXXA in patients who have congestive heart failure and monitor patients closely following infusion.
Patients receiving re-treatment may be at increased risk for anaphylaxis and infusion reactions and should be monitored carefully.
ADVERSE REACTIONSThe most commonly reported serious adverse reactions are anaphylaxis, infusion reactions and gout flares. Most common adverse reactions: gout flares (77%), infusion reactions (26%), nausea (12%), contusion or ecchymosis (11%), nasopharyngitis (7%), constipation (6%), chest pain (6%), anaphylaxis (5%), and vomiting (5%). Please see the Full Prescribing Information and Medication Guide at http://www.krystexxa.com/. ABOUT REFRACTORY CHRONIC GOUT Gout is a painful, debilitating form of arthritis and affects approximately eight million people in the U.S. alone. A significant sub-population of gout patients, approximately 120,000, are burdened with a difficult-to-treat form of the condition, known as refractory chronic gout (RCG). Symptoms of gout are caused by the body's response to the presence of uric acid crystals in the joints and surrounding tissue, which form when uric acid levels in the blood are elevated (a condition called hyperuricemia). The longer hyperuricemia persists, the higher the risk of developing gout. Symptoms of gout may include painful flares, pain or swelling in the joints (known as "gouty arthritis") or deposits of uric acid crystals under the skin, called "tophi." In cases of RCG, these symptoms may have a major influence on patient health-related quality of life due to the frequency and severity of episodes, the recurrent pain and the disfigurement associated with this condition. Although most cases of gout can be controlled with conventional urate-lowering therapy, when uric acid levels remain high and symptoms persist despite treatment efforts, chronic gout may be defined as refractory.