FDA Approves Drug for Duchenne Muscular Dystrophy

Feb. 10, 2017 -- A new drug to treat Duchenne muscular dystrophy has been approved by the U.S. Food and Drug Administration.

The tablet and liquid forms of Emflaza (deflazacort) were approved to treat patients age 5 years and older. The drug is a corticosteroid that reduces inflammation and slows the activity of the immune system.

Corticosteroids are used in many other countries to treat Duchenne muscular dystrophy, but this is the first FDA approval of a corticosteroid to treat the disease, and the first approval of deflazacort for any use in the United States.

Duchenne muscular dystrophy is the most common type of muscular dystrophy. The genetic disorder typically appears at ages 3 to 5 years and causes progressive muscle deterioration and weakness. Patients typically die in their 20s or 30s.

The FDA's approval of Emflaza -- marketed by Marathon Pharmaceuticals of Illinois -- is based on two studies showing that male patients who took the drug had improvements in muscle strength and appeared to lose the ability to walk later than those who took a placebo.

Common side effects of the drug are similar to those of other corticosteroids and include: facial puffiness, weight gain, increased appetite, upper respiratory tract infection, cough, haveig to urinate often during the daytime, unwanted hair growth, and excessive fat around the stomach, according to the FDA.

Less common side effects include: endocrine function problems, increased risk of infection, higher blood pressure, risk of gastrointestinal perforation, serious skin rashes, behavioral and mood changes, decrease in the density of the bones, and vision problems such as cataracts.