Efficacy and Safety of Once Daily Dosing vs. Approved On/Off Dosing of Edaravone Oral Suspension Up to 48 Weeks in Patients With Amyotrophic Lateral Sclerosis (Study MT-1186-A02).

Introduction/aims: An On/Off dosing regimen of intravenous (IV) edaravone and edaravone oral suspension is approved in the US for the treatment of amyotrophic lateral sclerosis (ALS). Placebo-controlled clinical trials showed IV edaravone slows the rate of physical functional decline. This study evaluated whether investigational daily dosing displayed superior efficacy vs. approved on/off dosing of edaravone oral suspension, and assessed safety and tolerability, over 48 weeks in patients with ALS.

Methods: Study MT-1186-A02 (NCT04569084) was a multicenter, phase 3b, double-blind, parallel group, superiority study that randomized patients to edaravone oral suspension (105-mg dose) administered Once Daily or the same edaravone oral suspension dose administered according to the approved On/Off regimen including placebo to mimic daily drug dosing. Patients had definite or probable ALS, baseline forced vital capacity ≥ 70%, and baseline disease duration ≤ 2 years. The primary endpoint was a combined assessment of function and survival (CAFS) at week 48, which included change in ALS Functional Rating Scale-Revised (ALSFRS-R) and time to death.

Results: CAFS at week 48 indicated Once Daily dosing did not show a statistically significant difference vs. approved on/off dosing (p = 0.777). Both dosing regimens provided comparable change from baseline ALSFRS-R total score to week 48 (least squares mean difference: 0.27 [95% CI -1.43 to 1.97]). Edaravone oral suspension was well tolerated, and no new safety concerns were identified in either group.

Discussion: Daily edaravone oral suspension did not show superiority and had equivalent safety and tolerability vs. the approved On/Off regimen, reinforcing the appropriateness of the approved dosing regimen.