A transdermal edaravone patch for amyotrophic lateral sclerosis (ALS) : preparation method using calcium silica

Daisuke Uesugi – Researcher, Shima Trading Co., LTD.; Yuji Saeki – Assistant Manager, Pharmaceuticals Dept., Shima Trading Co., LTD.; Takafumi Sanada – Department Manager, Pharmaceuticals Dept., Shima Trading Co., LTD.; Satoshi Murao – Assistant Professor, Pharmacy, Osaka Ohtani University; Masahiro Murakami – Guest Professor, Pharmacy, Osaka Ohtani University

Introduction: Amyotrophic lateral sclerosis (ALS) is associated with unmet medical needs. An edaravone oral suspension is used to slow the progression of functional disabilities, but there is a risk of aspiration, and fasting time increases. We studied the use of a transdermal edaravone patch to improve the quality of life of patients with ALS [1]. During patch formulation, relatively large amounts of solvent are needed to ensure that the drug content is applicable for clinical use, because edaravone has limited solubility in solvents. Here, we describe the utility of calcium silica as a filler for patches.