The FDA today approved Elelyso (taliglucerase alfa) for long term enzyme replacement therapy to treat a form of Gaucher disease, a rare genetic disorder.
Gaucher disease occurs in people with a deficiency of the enzyme glucocerebrosidase. The enzyme deficiency results in deposition of lipids in the spleen, liver, kidneys, and other organs. The major signs of Gaucher disease include liver or spleen damage, anemia, low blood platelet counts, and bone problems.
Elelyso is an injection that replaces the missing enzyme in patients with a confirmed diagnosis of Type I (non-neuropathic) Gaucher disease and should be administered by a health care professional every other week.
Due to the small number of affected patients, the efficacy of Elelyso was evaluated in a total of 56 patients with Type 1 Gaucher disease enrolled in two clinical trials. Many of these patients continued treatment on a longer-term extension study.
In one multi-center, double-blind, parallel-dose trial, the efficacy of Elelyso for use as an initial therapy was evaluated in 31 adult patients who had not previously received enzyme replacement therapy. Patients were randomly selected to receive Elelyso at a dose of either 30 or 60 units per kilogram.
At both doses, Elelyso was effective in reducing spleen volume, the study’s primary endpoint, from baseline by an average of 29% in patients receiving the 30 units/kg dose and by an average of 40% in patients receiving the 60 units/kg dose after nine months of treatment. Improvements in liver volume, blood platelet counts, and red blood cell (hemoglobin) levels also were observed.
In the other study, the efficacy of Elelyso was assessed in 25 patients with Type 1 Gaucher disease who were switched from imiglucerase, another enzyme replacement therapy product. In this multi-center, open-label, single-arm trial, patients who had been receiving treatment with imiglucerase for at least two years were switched to Elelyso infusions every other week at the same dose of imiglucerase. Results showed Elelyso was effective in maintaining spleen and liver volumes, blood platelet counts, and hemoglobin levels over a nine month evaluation period.
The most common side effects reported during clinical studies were infusion and allergic reactions. Symptoms of infusion reactions include headache, chest pain or discomfort, weakness, fatigue, hives, skin redness, increased blood pressure, back pain, joint pain, and flushing. As with other intravenous protein products, anaphylaxis has been observed in some patients during Elelyso infusions.
Other commonly observed side effects observed in greater than 10% of patients treated with Elelyso included upper respiratory tract infection, common cold-like symptoms (nasopharyngitis), joint pain (arthralgia), influenza, headache, extremity pain, back pain, and urinary tract infections.
Elelyso is manufactured and distributed by New York City-based Pfizer Inc., under license from Protalix BioTherapeutics Inc.