The Food and Drug Administration approved the antioxidant drug edaravone on May 5 for the treatment of amyotrophic lateral sclerosis, making it only the second drug ever to be approved by the agency for the motor neuron disease.
The FDA granted approval for edaravone, to be marketed by Mitsubishi Tanabe Pharma America under the brand name Radicava, through its orphan drug pathway, which is meant for drugs used to treat rare diseases or conditions. The Centers for Disease Control and Prevention estimates that amyotrophic lateral sclerosis (ALS) affects 12,000-15,000 Americans.
“After learning about the use of edaravone to treat ALS in Japan, we rapidly engaged with the drug developer about filing a marketing application in the United States,” said Eric Bastings, MD, deputy director of the division of neurology products in the FDA’s Center for Drug Evaluation and Research, said in the agency’s announcement. “This is the first new treatment approved by the FDA for ALS in many years, and we are pleased that people with ALS will now have an additional option.”
Mitsubishi Tanabe Pharma America demonstrated the efficacy of edaravone in a 6-month trial of 137 Japanese ALS patients. At 24 weeks, individuals who received edaravone had less decline on a clinical assessment of daily functioning, the ALS Functional Rating Scale-Revised (ALSFRS-R), compared with those who received a placebo. The difference in decline between the two groups was 33%, or a total of 2.49 points, on the ALSFRS-R. Most of the patients in the study also received the only other drug approved for ALS, riluzole (Rilutek).
Edaravone is thought to confer neuroprotection in part through its free radical–scavenging activity.
The adverse events most often reported by clinical trial participants who took edaravone included bruising and gait disturbance. The FDA also warned that edaravone is associated with hives, swelling, or shortness of breath, and allergic reactions to an ingredient in the drug, sodium bisulfite, which may cause anaphylactic symptoms that can be life-threatening in people with sulfite sensitivity.
The drug is administered via 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 14 days drug-free.
Mitsubishi Tanabe Pharma America said in a statement that it has created a patient access program called Searchlight Support for people with ALS who are prescribed the drug. The program provides personal case management, reimbursement support, and 24/7 clinical support.
In 2015, edaravone was approved for use as a treatment for ALS in Japan and South Korea.