The FDA has approved edaravone (Radicava) for the treatment of amyotrophic lateral sclerosis (ALS), the first new treatment OK'd for the condition in several years, the agency said.
The drug is an antioxidant that relieves the effects of oxidative stress in ALS by neutralizing lipid peroxyl radicals and peroxynitrite, preventing injury to blood vessels and neurons, according to drugmaker Mitsubishi Tanabe.
Edaravone was approved to treat ALS in Japan in June 2015, but had been approved in that country since 2002 to help ease brain damage following a stroke.
The FDA said the drug's efficacy was demonstrated in a six-month trial in Japan, which had enrolled 137 patients who were randomized to edaravone or placebo. At week 24, those on the drug had less decline on a clinical assessment of daily functioning compared with those on placebo.
that there were two phase III trials of the drug in Japan; the first , but the second -- which enrolled patients who had better function at baseline -- found the drug worked for these mildly symptomatic patients.
The FDA said adverse events were similar between groups, and the most common adverse reactions were bruising and gait disturbance.
The agency also noted the drug is associated with risks that require medical care such as hives, swelling, shortness of breath, and allergic reactions to sodium bisulfite -- an ingredient that can cause anaphylactic symptoms that can be life-threatening in people with sulfite sensitivity.
Edaravone is given as an intravenous infusion, with an initial treatment cycle of daily dosing for 14 days, followed by a 14-day drug-free period. Subsequent treatment cycles consist of dosing on 10 of 14 days, followed by another two-week drug-free period.
Eric Bastings, MD, deputy director of the Division of Neurology Products in the FDA's Center for Drug Evaluation and Research, said in a statement that once the FDA learned about the use of the drug to treat ALS in Japan, the agency "rapidly engaged with the drug developer about filing a marketing application in the United States."
In the U.S., the drug had been granted orphan drug designation -- raising questions about a potentially high price tag, despite the fact that generic versions of the drug are available in China and India, according to Alzforum.
The CDC estimates that 12,000 to 15,000 Americans have ALS.