Deferasirox (Exjade) Gets FDA Nod for Removal of Excess Iron in Patients With Genetic Blood Disorder
Agency also clears imaging companion diagnostic to detect liver iron concentration (Jan. 23)
The FDA has expanded the approved use of deferasirox (Exjade, Novartis) to treat patients aged 10 years and older who have chronic iron overload resulting from a genetic blood disorder called non–transfusion-dependent thalassemia (NTDT).
NTDT is a milder form of thalassemia that does not require individuals to undergo frequent red blood cell (RBC) transfusions. However, over time, some patients with NTDT are still at risk for iron overload, which can lead to damage to vital organs.
The FDA has also authorized marketing of FerriScan (Resonance Health) as an imaging companion diagnostic for deferasirox. The agency previously cleared FerriScan for measuring the liver iron concentration (LIC), but its use in clinical studies of deferasirox to select patients for therapy and to manage therapy defined its role as an imaging companion diagnostic necessary for the safe and effective use of deferasirox. FerriScan measures LIC noninvasively using magnetic resonance imaging (MRI).
An estimated 1,000 people in the U.S. have thalassemia, according to the National Heart, Lung, and Blood Institute. Thalassemia conditions can cause the body to make fewer healthy RBCs and less hemoglobin — a protein that carries oxygen to all parts of the body and returns carbon dioxide to the lungs so it can be exhaled. Some patients with thalassemia require frequent transfusions of RBCs to maintain an acceptable level of hemoglobin. Iron overload is common in these patients.
Exjade (deferasirox) was previously approved for the treatment of chronic iron overload due to blood transfusions in patients aged 2 years and older. The new approval extends its use to the treatment of patients with NTDT who show iron overload. Deferasirox should be used in patients with NTDT who have an LIC of at least 5 mg of iron per gram of dry liver tissue weight.
The safety and effectiveness of deferasirox to treat chronic iron overload in patients with NTDT were established in two clinical trials designed to measure the number of patients whose LIC was reduced to less than 5 mg per gram dry weight after 52 weeks of treatment. In the first trial, 166 patients were randomly assigned to receive daily treatment with 5 mg/kg of deferasirox, 10 mg/kg of deferasirox, or placebo. The results showed that 15% and 27% of deferasirox-treated patients achieved the target LIC, respectively, compared with 4% of placebo-treated patients. The second trial included 133 patients from the first study who received an additional year of treatment with deferasirox or switched from placebo to deferasirox. Thirty-five percent of the evaluable patients in this extension trial achieved the target LIC.
Source: FDA; January 23, 2013.