A recent study analyzed the minimal clinically important change (MCIC) in total motor Abnormal Involuntary Movement Scale (AIMS) score in patients with tardive dyskinesia (TD) treated with deutetrabenazine. Deutetrabenazine is an approved medication for TD. The study included 295 patients, with 197 receiving deutetrabenazine and 98 receiving a placebo. The analysis found that the MCIC in deutetrabenazine-treated patients was approximately -2.4 based on the Patient Global Impression of Change (PGIC) and -2.1 based on the Clinical Global Impression of Change (CGIC). In comparison, the MCIC for placebo-treated patients was -1.4 based on the PGIC and -1.5 based on the CGIC. Additionally, a significant proportion of deutetrabenazine-treated patients showed improvement in total motor AIMS score by at least 2 and 3 points. These findings suggest that a reduction in total motor AIMS score of approximately 2 is associated with clinically meaningful improvement in TD symptoms when treated with deutetrabenazine.
Reference: Hauser RA, Barkay H, Wilhelm A, Wieman M, Savola JM, Gordon MF. Minimal clinically important change in Abnormal Involuntary Movement Scale score in tardive dyskinesia as assessed in pivotal trials of deutetrabenazine. Parkinsonism Relat Disord. 2022;97:47-51. doi:10.1016/j.parkreldis.2022.02.017