Background: In a Phase 3 study, amyotrophic lateral sclerosis (ALS) patients experienced significantly less physical functional decline with 24-week edaravone vs placebo, followed by open-label treatment for an additional 24 weeks.Methods: Outcome (the change in ALS Functional Rating Scale-Revised, ALSFRS-R, from baseline) was projected for placebo patients through 48 weeks and compared with 48-week edaravone or 24-week edaravone after switching from placebo.Results: A total of 123 patients received open-label treatment (65 edaravoneedaravone; 58 placebo-edaravone). The projected ALSFRS-R decline for placebo from baseline through week 48 was greater than for 48-week edaravone (P < .0001). For patients switching from placebo to edaravone, ALSFRS-R slope approached that of continued edaravone for 48 weeks. ALSFRS-R decline did not differ between actual and projected edaravone through week 48.Conclusions: Compared with placebo, these analyses suggest that edaravone is beneficial in ALS patients even after 6 mo of receiving placebo, and efficacy is maintained for up to 1 year. K E Y W O R D S

Introduction/Aims An intravenous (IV) formulation of edaravone has been shown to slow the rate of physical functional decline in amyotrophic lateral sclerosis (ALS). An oral suspension formulation of edaravone was recently approved by the United States Food and Drug Administration for use in patients with ALS. This study assessed the safety and tolerability of oral edaravone. Methods This global, open‐label, phase 3 study evaluated the long‐term safety and tolerability of oral edaravone in adults with ALS who had a baseline forced vital capacity ≥70% of predicted and disease duration ≤3 y. The primary safety analysis was assessed at weeks 24 and 48. Patients received a 105‐mg dose of oral edaravone in treatment cycles replicating the dosing of IV edaravone. Results The study enrolled 185 patients (64.3% male; mean age, 59.9 y; mean disease duration, 1.56 y). The most common treatment‐emergent adverse events (TEAEs) at week 48 were fall (22.2%), muscular weakness (21.1%) and constipation (17.8%). Serious TEAEs were reported by 25.9% of patients; the most common were worsening ALS symptoms, dysphagia, dyspnea, and respiratory failure. Twelve TEAEs leading to death were reported. Forty‐six (24.9%) patients reported TEAEs that were considered related to study drug; the most common were fatigue, dizziness, headache, and constipation. Sixteen (8.6%) patients discontinued study drug due to TEAEs. No serious TEAEs were related to study drug. Discussion This study indicated that oral edaravone was well tolerated during 48 wk of treatment, with no new safety concerns identified.

Objectives: The edaravone development program established a study design in which a treatment effect slowing functional loss in amyotrophic lateral sclerosis (ALS) could be documented within a 24-week time frame. This report elucidates the strategic enrichment design utilized to create efficiency and precision in the development program. Methods: Post-hoc analyses describe learning, sequential iteration, and evolution in study design. Results: The first Phase 3 study of edaravone in ALS (Study MCI186-16) included a large proportion (35%) of placebo patients who were minimal progressors. These patients demonstrated high heterogeneity in change in ALSFRS-R score (À4 median with interquartile range [IQR] 7.5) and a modal distribution score of 0, suggesting evidence of minimal change in ALSFRS-R during the study. This level of variability and rate of progression may have made it difficult to detect a prospective treatment effect in the study. A strategic enrichment strategy provided the second Phase 3 study (Study MCI186-19) with the ability to detect a treatment effect. In Study MCI186-19, only 13% of the placebo patients were minimal progressors. Further, these placebo patients demonstrated less heterogeneity and greater functional progression of ALS, thereby providing greater likelihood of detecting a treatment effect. The enrichment strategy may have excluded some rapidly progressing patients, potentially supporting the detection of a treatment effect. As previously published, Study MCI186-19 prospectively documented a 33% reduction in rate of progression of ALS (p ¼ 0.0013). Conclusions: Strategic choices in the design of Study MCI186-19 reduced the proportion of minimally progressing patients and supported detection of a treatment effect.

ObjectiveThis was a post hoc analysis of the Edaravone Phase III Study MCI186-19 (‘Study 19’) to examine the utility of clinical staging systems as end points in clinical trials in amyotrophic lateral sclerosis (ALS).MethodsAmyotrophic Lateral Sclerosis Functional Rating Scale—Revised item scores from Study 19 were retrospectively mapped to King’s stage and Milano-Torino staging (MiToS) stage. We assessed the percentage of patients who experienced progression in King’s and MiToS stages during Study 19. We also assessed disease progression in subgroups of patients according to baseline King’s stage.ResultsDuring double-blind treatment, the percentage of patients who experienced a progression in King’s stage was lower for edaravone (42.0%, 95% CI 30.4% to 53.6%) than placebo (55.9%, 95% CI 44.1% to 67.6%). The most pronounced effect was noted among patients who were in stage 1 and was maintained throughout open-label treatment. An analysis of a ≥2-stage progression in MiToS stage showed no difference between treatment arms during double-blind treatment, but during the open-label period, more rapid progression was noted among patients in the placebo–edaravone arm than among those in the edaravone–edaravone arm (log-rank test, p<0.001).ConclusionsThe King’s and MiToS staging systems provided utility in assessing clinical progression in Edaravone Study 19. These findings may support the use of staging systems as end points in ALS clinical trials and to understand the timing of benefit as measured by these scales.

Background Edaravone slowed the rate of functional decline in subjects with amyotrophic lateral sclerosis (ALS) in phase 3 study MCI186-19 (Study 19). One of the Study 19 inclusion criteria was forced vital capacity (FVC) ≥80% of predicted (≥80%p). Therefore, the study provided no information on edaravone efficacy in subjects with FVC <80%p. In Study 19, 24-week, double-blind treatment was followed by open-label treatment where all subjects received edaravone. At 24 weeks, some subjects had FVC <80%p (FVC24 <80%p). This allowed for post-hoc assessment of the effects of edaravone in subgroups of subjects with FVC24 ≥80%p vs <80%p. Objective To address the question of the efficacy of edaravone in ALS patients with FVC <80%p. Methods Post-hoc analysis of Study 19 comparing edaravone efficacy at week 48 in subjects with FVC24 ≥80%p vs <80%p. Results With edaravone treatment, subjects in both the FVC24 ≥80%p and the FVC24 <80%p subgroups experienced a reduction in ALS Functional Rating Scale-Revised (ALSFRS-R) score loss vs placebo subjects through week 48. For the FVC24 ≥80%p subgroup, the changes in ALSFRS-R scores from baseline to week 48 were −7.63 for edaravone-edaravone vs −9.69 for placebo-edaravone, a difference of 2.05 (P = .034; 95% CI: 0.16, 3.94). For the FVC24 <80%p subgroup, the changes in ALSFRS-R scores from baseline to week 48 were −10.26 for edaravone-edaravone vs −15.20 for placebo-edaravone, a difference of 4.94 (P = .0038; 95% CI: 1.64, 8.25). Linear regression analysis indicated that, in the FVC24 <80%p subgroup, there was a notable change in the slope of the ALSFRS-R score-vs-time graph after the start of edaravone treatment. Conclusion ALS subjects in the Study 19 placebo arm had a slowing in disease progression, even when edaravone was added with an FVC of <80%p prior to starting edaravone. A randomized, placebo-controlled study is needed to validate these post-hoc findings.