Neurological Disorders

Comparative Study of the Free Radical Scavenging Activities of Original and Generic Edaravone Determined by Electron Spin Resonance

Abstract

Jimbo H, Ikeda Y and Chang-il Lee M

Edaravone, a powerful free radical scavenger, is the drug available in the clinical practice for the treatment of cerebral infarction and amyotrophic lateral sclerosis. Recently, many generic Edaravone injections have been commercialized. Substitution of additives in generic injections has the potential effect of changing the antioxidant ability of the original Edaravone injection. We investigated the dissimilarity between original and generic Edaravone injections focusing on their free radical scavenging activities determined by electron spin resonance spectroscopy. There were no significant differences between the original and generic Edaravone regarding the antioxidant abilities toward the hydroxyl radical. However, the generics in which the additive L-cysteine was substituted with glycerin or citric acid showed significant reduction in their antioxidant activity toward superoxide (p <0.01). Our in vitro findings suggest that the antioxidant ability of generic Edaravone against the hydroxyl radical is equivalent to that of the original Edaravone and that substitution of additives in the generic Edaravone might change its antioxidant activity toward the superoxide.