In vitro studies have revealed EPI-589 as more protective of cell viability against oxidative stress than edaravone (approximately 1000 times more potent with a difference in half maximal effective concentration for fibroblast cells derived from patients with ALS with FUS c.1566G>A mutation and SOD1 E50K mutation) [19,20]. This evidence concerns the gene FUS and amyotrophic lateral sclerosis.