Long-Term Efficacy and Safety of Deutetrabenazine in Patients With Tardive Dyskinesia: Post Hoc Subgroup Analysis by Race
Background: Deutetrabenazine demonstrated clinically significant improvements in Abnormal Involuntary Movement Scale (AIMS) scores in 12-week pivotal tardive dyskinesia (TD) trials (ARM-TD [NCT02195700]/AIM-TD [NCT02291861]). African descent has been identified as a risk factor for TD. This post hoc analysis assessed long-term efficacy and safety of deutetrabenazine by racial subgroups.
Methods: Patients who completed ARM-TD or AIM-TD enrolled in this 3-year, open-label extension study (NCT02198794), with deutetrabenazine dose titrated based on dyskinesia control and tolerability. Change from baseline in total motor AIMS score (items 1–7), Patient Global Impression of Change (PGIC) and Clinical Global Impression of Change (CGIC) treatment success, and adverse event (AE) rates were analyzed in racial subgroups.
Results: Of 337 patients, 264 were White (mean age, 58 years; 43% male) and 73 were non-White (including 69 Black, 2 Asian, 1 American Indian or Alaskan Native; mean age, 54 years; 48% male). Mean baseline total motor AIMS score was 8.8 in both groups. At Week 145, mean (SE) dose was 39.6 mg/d (0.9) in White patients and 38.5 mg/d (2.0) in non-White patients. Mean (SE) changes from baseline in AIMS score were −6.5 (0.42) and −7.5 (0.76); 61% and 77% achieved PGIC treatment success and 71% and 86% achieved CGIC treatment success, respectively. AE incidence was low (exposure-adjusted incidence rates [incidence/patient-year]: any, 1.28 and 1.11; serious, 0.11 for both groups; leading to discontinuation, 0.06 and 0.05).
Conclusion: This analysis suggests that deutetrabenazine for long-term treatment of TD is beneficial, with a favorable safety profile, in White and non-White patients.
