Background: Tardive dyskinesia (TD) is managed by dose reduction or interruption of dopamine-receptor antagonists (DRAs), possibly causing psychiatric disorder relapse. Deutetrabenazine (DTB) was efficacious and safe for the treatment of TD in the ARM-TD and AIM-TD trials regardless of baseline DRA use or comorbidities.
Objective: To evaluate the efficacy and safety of long-term DTB by DRA use or psychiatric disorder.
Methods: This open-label, single-arm, long-term extension trial included patients who completed ARM-TD or AIM-TD. Change in Abnormal Involuntary Movement Scale (AIMS) scores from baseline, treatment success assessed using the Clinical Global Impression of Change (CGIC) or Patient Global Impression of Change (PGIC) at Week 54 were analyzed by psychotic or mood disorders, and presence of current DRA use.
Results: At Week 54, meaningful improvements in AIMS scores (mean [standard error]) were observed for patients with mood disorders (–5.2 [0.93]) and psychotic disorders (–5.0 [0.63]), and in patients currently using (–4.6 [0.54]) or not using DRAs (–6.4 [1.27]). Treatment success rates were 73% and 71% on CGIC, and 62% and 57% on PGIC in patients with mood or psychotic disorders; and 71% and 74% on CGIC, and 58% and 63% on PGIC, stratified by current DRA use. Prior treatment did not impact long-term treatment response. The frequency of dose modification or interruption due to AEs was low regardless of psychiatric comorbidities or DRA use.
Conclusions: Clinicians and patients reported meaningful improvement in TD symptoms with long-term DTB treatment regardless of underlying psychiatric illness or DRA use.