The use of valbenazine was shown to significantly improve tardive dyskinesia in patients with schizophrenia, schizoaffective disorder, and other mood disorders, according to supplemental analysis results published in the Journal of Clinical Psychiatry.
The US Food and Drug Administration (FDA) approval of valbenazine in patients with tardive dyskinesia was based on preliminary results from the KINECT 3 trial. Additional findings from the phase 3 study were assessed to present more clinically relevant results. Study participants (n=202) were given valbenazine 40 mg, 80 mg, or a placebo once daily for a total of 6 weeks. Treatment efficacy was measured using changes in the Abnormal Involuntary Movement Scale (AIMS) total score (items 1 to 7).
After post hoc analysis, the researchers reported that medium-to-high effect sizes were seen for mean changes in AIMS total score from baseline to week 6 (40-mg group: −1.8, d=0.52; 80-mg group: −3.1, d=0.89). In addition, AIMS total score treatment responses between 10% and 70% improvement were found to be statistically significant in the valbenazine 80-mg arm vs placebo (P ≤.01).
Researchers noted that the KINECT 3 study was not designed to test all the post hoc analyses presented.
“Results from these supplemental AIMS analyses indicated a consistently stronger effect with valbenazine versus placebo, with sustained improvements during double-blind long-term valbenazine treatment,” the researchers wrote.
“It is hoped that these analyses will help clinicians interpret clinical trial data and make relevant treatment decisions for their patients with [tardive dyskinesia],” they concluded.
Correll CU, Cutler AJ, Kane JM, McEvoy JP, Liang GS, O’Brien CF. Characterizing treatment effects of valbenazine for tardive dyskinesia: additional results from the KINECT 3 study. J Clin Psychiatry. 2018;80(1):18m12278.