Research shows that approximately 1 in 4 patients with chronic exposure to antipsychotics develops TD. While there are several strategies for managing TD, to date no medications have been approved by the Food and Drug Administration (FDA) for the treatment of TD.
For the study, Robert Hauser, M.D., M.B.A., of the University of South Florida and colleagues randomly assigned 234 patients with schizophrenia, schizoaffective disorder, or a mood disorder to take valbenazine (40 mg/day or 80 mg/day) or placebo daily for six weeks. All patients in the trial had moderate-to-severe TD at screening, and approximately 85% were also taking antipsychotics throughout the trial. The researchers compared change from baseline in dyskinesia scores on the Abnormal Involuntary Movement Scale (AIMS, items 1–7) at two, four, and six weeks.
A total of 205 patients completed the study. The mean change from baseline to week six of the AIMS dyskinesia score was −3.2 for the 80 mg/day group, compared with −0.1 for the placebo group, a significant difference. The mean AIMS dyskinesia score was also reduced in the 40 mg/day group (−1.9 compared with −0.1). Valbenazine was generally well tolerated, with somnolence, akathisia, and dry mouth reported by 5.3%, 3.3%, and 3.3% of patients in both dosage groups, respectively.
“These findings add to a growing body of evidence showing that valbenazine is effective … at reducing the severity of movements in patients with moderate-to-severe TD,” said Stanley Caroff, M.D., an emeritus professor of psychiatry at the Perelman School of Medicine at the University of Pennsylvania, who not involved with the study. “Although many fundamental questions remain—including concurrent changes in antipsychotic and anticholinergic therapy, the course and outcome of TD in long-term investigations, and relative costs of treating TD—the availability of an agent that significantly suppresses manifestations of TD would be extremely valuable in reducing the stigma and embarrassment that accompanies TD, thereby enhancing social rehabilitation and recovery efforts," Caroff concluded.
In 2016, Neurocrine announced that the FDA was reviewing the company’s New Drug Application (NDA) for valbenazine for the treatment of TD. According to a press release by the company, the FDA is expected to reach a decision by April 11, 2017.
For related information, see the Psychiatric News article “New Hope for Patients With Tardive Dyskinesia,” by Stanley Caroff, M.D.