Exploratory double-blind, parallel-group, placebo-controlled study of edaravone (MCI-186) in amyotrophic lateral sclerosis (Japan ALS severity classification: Grade 3, requiring assistance for eating, excretion or ambulation).

Our objective was to explore the efficacy and safety of edaravone in amyotrophic lateral sclerosis (ALS) patients with a Japan ALS severity classification of Grade 3. In a 24-week, double-blind, randomized study, 25 patients who met all of the following criteria were enrolled: Japan ALS severity classification Grade 3; definite, probable, or probable-laboratory supported ALS (El Escorial/revised Airlie House); forced vital capacity (%FVC) ≥60%; duration of disease ≤3 years at consent; and change in the revised ALS functional rating scale (ALSFRS-R) score of -1 to -4 points during the 12-week pre-observation period. Patients received edaravone (n = 13) or placebo (n = 12) for six cycles. The efficacy outcome was change in the ALSFRS-R score. The least-squares mean change in the ALSFRS-R score ± standard error during the 24-week treatment was -6.52 ± 1.78 in the edaravone group and -6.00 ± 1.83 in the placebo group; the difference of -0.52 ± 2.46 was not statistically significant (p = 0.835). Incidence of adverse events was 92.3% (12/13) in the edaravone group and 100.0% (12/12) in the placebo group. There was no intergroup difference in the changes in the ALSFRS-R score. The incidences of adverse events were similar in the two groups.