Deutetrabenazine Reduces Severe Tardive Dyskinesia Movements in a 3-year Open-Label Extension Trial

Background: There are no established treatment guidelines for tardive dyskinesia (TD) based on movement severity. The 12-week ARM-TD and AIM-TD studies in TD patients with baseline Abnormal Involuntary Movement Scale (AIMS) total score (items 1-7) ‚ ≥6 showed clinically significant improvements in AIMS score with deutetrabenazine vs placebo. Patients who completed these studies were eligible for the open-label extension (OLE) trial. This post-hoc analysis evaluated deutetrabenazine in TD patients with severe movements.

Methods: Subgroups were defined by upper quartile of baseline total AIMS score (local rating). Endpoints were change and percent change from baseline in AIMS score, and percent of patients achieving ‚ ≥50% AIMS reduction from baseline.

Results: 337 patients were analyzed. The upper quartile of baseline total AIMS score was 14. Subgroups were defined as >14 and ‚≤14 at baseline, respectively (n=64 vs 273); data are presented at Wk 145 (n=40 vs 120). Mean treatment duration was 880.5 and 760.8 days. Mean[±SE] daily doses were 41.1(1.6)mg and 38.9(1.0)mg. Mean[±SE] change from baseline in AIMS score was -11.0(0.8) vs -5.1(0.3); percent change from baseline was -60.1(3.6)% vs -55.9%(3.0)%. More patients with AIMS score >14 had ‚â•50% AIMS reduction (73% vs 65%). Less patients discontinued (38% vs 51%); reasons included withdrawal by subject (16% vs 25%), adverse event (3% vs 11%), and lost to follow-up (6% vs 7%). Withdrawal due to lack of efficacy was uncommon (5% vs 2%).

Conclusions: Patients with baseline total AIMS score >14 had clinically meaningful reductions in AIMS score, suggesting deutetrabenazine has long-term benefit in these patients.