18. LONG-TERM SAFETY AND EFFICACY OF DEUTETRABENAZINEIN PATIENTS AGED ≥ 65 YEARS WITH TARDIVE DYSKINESIA

Introduction

Tardive dyskinesia (TD) is an involuntary, hyperkinetic movement disorder more prevalent in older patients. Deutetrabenazine is approved by the United States Food and Drug Administration for the treatment of TD based on results from two 12-week trials, ARM-TD and AIM-TD, which demonstrated significant improvements in Abnormal Involuntary Movement Scale (AIMS) score, as well as favorable safety/tolerability, versus placebo. This analysis assessed the long-term safety and efficacy of deutetrabenazine in patients with TD aged LESS THAN 65 or ≥65 years.

Methods

Patients who completed either ARM-TD or AIM-TD could enroll in this 3-year, single-arm, open-label extension study (NCT02198794). Change from baseline and ≥50% response rate for AIMS score, treatment success defined as “much improved” or “very much improved” on Clinical Global Impression of Change (CGIC) or Patient Global Impression of Change (PGIC), and safety were assessed at Week 145.

Results

Among 337 participants, 258 were aged LESS THAN 65 years and 79 were aged ≥65 years. At Week 145, 50% (130/258) of patients aged LESS THAN 65 years and 51% (40/79) of patients aged ≥65 were receiving deutetrabenazine. The mean±SE total dose at Week 145 was 40.3±0.91 and 36.8±1.85 mg/d, respectively. The mean±SE changes in the AIMS score from baseline were −6.7±0.43 and −6.2±0.77 in the LESS THAN 65 and ≥65 years cohorts, respectively (percent change: −59.3%±2.70% and −50.0%±5.33%). 71% and 54% of patients in the LESS THAN 65 and ≥65-years cohorts, respectively, achieved ≥50% AIMS response. Most patients achieved treatment success per CGIC (LESS THAN 65, 71%; ≥65, 79%) and PGIC (LESS THAN 65, 65%; ≥65, 59%). Exposure-adjusted incidence rates (incidence/patient-years) were 1.13 and 1.76 for any adverse event, 0.01 and 0.02 for akathisia, 0.06 and 0.09 for somnolence and sedation, 0.06 and 0.18 for Parkinson-like events, and 0.06 and 0.16 for depression in LESS THAN 65 and ≥65-years cohorts, respectively.

Conclusions

Deutetrabenazine treatment was associated with improvements in the AIMS score from baseline to Week 145 and treatment success per CGIC and PGIC scores in both age cohorts. Deutetrabenazine was well tolerated in both older and younger patients with TD.