OBJECTIVE: Assess NLR response to edaravone oral suspension treatment in patients with amyotrophic lateral sclerosis (ALS) and whether baseline NLR may predict NLR response vs propensity score-matched Pooled Resource Open-Access ALS Clinical Trials (PRO-ACT) placebo controls.
BACKGROUND: The US Food and Drug Administration (FDA) approved an on/off dosing regimen of Radicava ORS® (edaravone) oral suspension for patients with ALS. In a retrospective analysis, edaravone ORS-treated patients with ALS from Studies MT-1186-A01/A02/A03/A04 showed a 7.3-month significantly prolonged mean survival vs matched PRO-ACT controls (P<0.001) over 34 months. Elevated neutrophil-to-lymphocyte ratio (NLR) is a potential prognostic biomarker for ALS, correlating with clinical deterioration. In some non-ALS oxidative stress disease models, edaravone treatment was associated with NLR decline, paralleling clinical improvement. DESIGN/METHODS: MT-1186-A01 (NCT04165824) was a phase 3, open-label, 48-week study conducted to evaluate the long-term safety and tolerability of FDA-approved on/off edaravone oral suspension; MT-1186-A03 (NCT04577404) was its 96-week extension. MT-1186-A02 (NCT04569084) was a phase 3b, double-blind study in patients randomized to an investigational drug once daily or FDA-approved on/off edaravone oral suspension regimen; MT-1186-A04 (NCT05151471) was its 48-week extension. MT-1186-A01/A02/A03/A04 patients were propensity score-matched 1:1 on 11 baseline variables with historical, PRO-ACT controls (placebo control patients may have received riluzole). RESULTS: Patients from Studies MT-1186-A01/02/03/04 (n=221) showed a numeric trend towards decreasing NLR at 48 weeks (least squares mean difference= −0.2851) vs matched PRO-ACT controls (n=221) (P=0.065). Patients were grouped by baseline NLR<3 or NLR≥3. Edaravone-treated patients with NLR<3 showed significantly lower NLR at 48 weeks (P=0.038) vs PRO-ACT controls. CONCLUSIONS: Edaravone oral suspension treatment in MT-1186 studies vs PRO-ACT controls supports the possible role of NLR as a novel ALS prognostic biomarker. These analyses were retrospective non-randomized comparisons, and there was a potential time bias between matched groups. Further studies are needed to validate NLR as a prognostic biomarker across ALS population.