Edaravone: a new hope for deadly amyotrophic lateral sclerosis

Amyotrophic lateral sclerosis (ALS), commonly known as Lou Gehrig's disease, is a fatal motor neuron degenerative disorder leading to paralysis and eventual death. At present, we do not have any specific cure for this deadly disorder. Current drug therapy can only reduce morbidity in ALS patients. In 1995, riluzole was the first drug approved by the U.S. Food and Drug Administration (FDA) for ALS. After a long gap of 22 years, Mitsubishi Tanabe Pharma America got U.S. FDA approval for edaravone (Radicava) in May 2017 for the management of ALS. Edaravone, a novel neuroprotective agent, is indicated to slow down progression of ALS. In 2015, Mitsubishi Tanabe Pharma launched edaravone (Radicut) for the treatment of stroke and ALS in Japan. The U.S. FDA approved edaravone following clinical evidence from three clinical trials conducted in 368 ALS patients in Japan. Edaravone is awaiting approval by the European Medicines Agency (EMA) in Europe. Edaravone (60 mg) is administered by very slow intravenous infusion (60 minutes) in 28-day cycles. It has been shown to slow down the loss of physical function in ALS patients by 33% as compared to placebo. Edaravone is a strong antioxidant that prevents oxidative stress from inducing motor neuron death in ALS patients. Being a potent free radical scavenger, it has been shown to inhibit nitration of tyrosine residues in the cerebrospinal fluid and improve motor functions in mouse models of ALS. The product has been patented and the FDA has not approved any generic version of edaravone. This article discusses the preclinical pharmacology, pharmacokinetics, safety profile, clinical studies and drug interactions of edaravone (Radicava) in ALS.