FDA Approves New Treatment for Rare Genetic Disease

The FDA on Tuesday granted approval to Genzyme’s eliglustat (Cerdelga), the only first-line oral therapy for patients with Type 1 Gaucher disease.

The rare genetic disease occurs in patients who do not produce enough of the enzyme glucocerebrosidase, which causes fatty materials to collect in the spleen, liver, and bone marrow. Eliglustat inhibits the metabolic process that forms the production of the fatty materials in those with the disease, which currently affects approximately 6000 people in the United States.

In a press release, Amy G. Egan, MD, MPH, deputy director of the FDA Office of Drug Evaluation III, said eliglustat's approval "offers another important treatment option for patients with Type 1 Gaucher disease. In addition to its approval, Cerdelga received orphan drug designation from the FDA, “reflecting the agency’s focus and commitment to the development of treatments for rare diseases,” added Dr. Egan.

Eliglustat was evaluated in 2 separate clinical studies that enrolled nearly 200 Gaucher disease patients. In the first double-blind, placebo-controlled trial, 40 patients with Type 1 Gaucher disease who had not received prior enzyme replacement therapy were evaluated over a period of 9 months.

After receiving a starting twice-daily dose of 42 mg, treatment with eliglustat showed a greater reduction in spleen volume from baseline to week 39 when compared with placebo. The drug also showed increased improvement in liver volume, blood platelet count, and hemoglobin level compared with placebo.

In the second trial, eliglustat was compared to an enzyme replacement therapy in 159 patients with Type 1 Gaucher disease who had been previously treated and stabilized on the drug imiglucerase. The trial found eliglustat treatment offered the same stabilization of hemoglobin level, platelet count, and spleen and liver volume as imiglucerase therapy.

In both clinical trials, common adverse events associated with eliglustat use included fatigue, headache, nausea, diarrhea, back pain, pain in extremities, and upper abdominal pain.

Genzyme anticipates eliglustat will be available to patients within a month, although a limited number of patients metabolizing eliglustat at a more rapid or undetermined rate will not be eligible for the treatment.

“Cerdelga is an important new option for people living with Gaucher disease Type 1,” said Rhonda Buyers, CEO of the National Gaucher Foundation, in a press release. “As enzyme replacement therapy is the standard of treatment for Gaucher disease, patients receive regular intravenous infusions for life. With FDA's approval of a first-line oral treatment, Cerdelga has the potential to be a valuable treatment option for people living with this serious disease.”