Systematic Review of Valbenazine Shows Its Efficacy
In April, 2017, valbenazine (Ingrezza) became the only medication approved by the US Food and Drug Administration (FDA) with a specific indication for treating tardive dyskinesia (TD).
This usually irreversible condition typically results from the use of dopamine receptor blockers to treat psychiatric disorders and is characterized by involuntary, repetitive, and aimless movements. Moreover, because patients’ social contacts may find these involuntary movements disconcerting, TD may further stigmatize many patients already stigmatized because of a psychiatric diagnosis.
To evaluate the clinical utility of valbenazine — a reversible inhibitor of vesicular monoamine transporter 2 (VMAT2) — Leslie Citrome (pictured), MD, MPH, clinical professor of psychiatry and behavioral sciences at New York Medical College in Valhalla, New York, recently conducted a systematic review of all available clinical reports of studies of valbenazine for the treatment of TD. Citrome then extracted the principal results of these studies and used them to calculate the number needed to treat (NNT) and the number needed to harm (NNH) for relevant outcomes. These two numbers are measures of a drug’s effect size, either positive (for NNT) or negative (for NNH), and indicate how many patients must be treated with one agent instead of another to obtain one more outcome of interest.
NYMC Faculty: Leslie L. Citrome, M.D., M.P.H., clinical professor of psychiatry & behavioral sciences