Ferriprox® (deferiprone) is used for the treatment of iron overload in patients with thalassemia. Such patients require long-term blood transfusions to treat their profound anemia; however, red blood cells are loaded with iron, and there is no physiologic pathway to eliminate excess iron from the body. Consequently, these patients are at risk for developing very high levels of iron in their circulation and vital organs. As the level of labile iron (iron not bound to proteins) rises, it begins to react with its environment to generate free radicals, which are toxic to proteins and membranes. The liver can tolerate fairly high levels of iron before it exhibits toxicity, but the heart and endocrine glands (pancreas, thyroid, hypothyroid, gonads, etc.), exhibit toxicity at much lower levels. Ferriprox works by binding to labile iron in the tissues and circulation, thereby inactivating it, and then removing it from the body, mostly via the urine. With this treatment, patients can continue to receive the blood transfusions they need to keep them alive without building up their body iron levels.
The Ferriprox molecule is unique. It has a low molecular weight and neutral charge and it is mostly bound to proteins in the blood which facilitates its ability to penetrate membranes to enter and remove labile iron from the intracellular sites.
INDICATIONS AND IMPORTANT SAFETY INFORMATION
FERRIPROX® (deferiprone) is an iron chelator indicated for the treatment of patients with transfusional iron overload due to thalassemia syndromes when current chelation therapy is inadequate.
Approval is based on a reduction in serum ferritin levels. There are no controlled trials demonstrating a direct treatment benefit, such as improvement in disease-related symptoms, functioning, or increased survival.
Limitation of Use: Safety and effectiveness have not been established for the treatment of transfusional iron overload in patients with other chronic anemias.
The safety and effectiveness of Ferriprox in pediatric patients have not been established.
IMPORTANT SAFETY INFORMATIONWARNING: AGRANULOCYTOSIS/NEUTROPENIA.
Ferriprox is contraindicated in patients with hypersensitivity to deferiprone or to any of the excipients in the formulation.
Ferriprox can cause fetal harm. Women should be advised of the potential hazard to the fetus and to avoid pregnancy while on this drug.
In clinical studies, 7.5% of 642 subjects treated with Ferriprox developed increased ALT values. Four (0.62%)Ferriprox-treated subjects discontinued the drug due to increased serum ALT levels and and 1 (0.16%) due to an increase in both ALT and AST. Monitor serum ALT values monthly during therapy with Ferriprox, and consider interruption of therapy if there is a persistent increase in the serum transaminase levels. Decreased plasma zinc concentrations have been observed on Ferriprox therapy. Monitor plasma zinc, and supplement in the event of a deficiency.
Avoid concomitant use with other drugs known to be associated with neutropenia or agranulocytosis; however, if this is not possible, closely monitor the absolute neutrophil count. Allow at least a 4-hour interval between Ferriprox and mineral supplements, and antacids that contain polyvalent cations (e.g., iron, aluminum, and zinc).
The most common (incidence ≥ 5%) adverse reactions are chromaturia, nausea, vomiting and abdominal pain, alanine aminotransferase increased, arthralgia, and neutropenia.