Long-term outcomes of edaravone in amyotrophic lateral sclerosis in South Korea: 72-week observational study

Abstract

Background Amyotrophic lateral sclerosis (ALS) is a lethal neurodegenerative disease characterized by the gradual loss of upper and lower motor neurons that leads to progressive muscle atrophy and weakness. Edaravone, a free-radical scavenger, was approved as an ALS treatment in 2015 in South Korea. Methods This study investigated the long-term effects and safety of edaravone by reviewing the medical records of 16 Korean patients with ALS who received extended edaravone between 2015 and 2021 in a single tertiary ALS center. Results Among sixteen patients, eleven patients underwent extended edaravone therapy for more than 18 cycles (72 weeks). The mean monthly changes in the revised ALS Functional Rating Scale (ALSFRS-R) were - 0.96 +/- 0.83 (0-24 weeks), - 0.70 +/- 0.76 (24-48 weeks), - 1.18 +/- 1.67 (48-72 weeks), and - 0.81 +/- 0.60 (0-72 weeks). The mean decline in forced vital capacity (FVC) was 17.4 +/- 24.1. The changes were significant in both ALSFRS-R (p < 0.001) and FVC (p = 0.048); however, the mean change in compound muscle action potential of phrenic nerves was not. Patients experienced only minor adverse events, which were well tolerated. Conclusions This study verifies previous reported outcomes of edaravone in 16 Korean ALS patients, indicating a modest effect with a favorable safety profile.