This study aims to evaluate clinical experiences with vesicular monoamine transporter 2 (VMAT2) inhibitors in pediatric hyperkinetic movement disorders.

VMAT2 inhibitors are often prescribed for the treatment of hyperkinetic movement disorders such as tics, stereotypy, tardive dyskinesia and chorea. Pediatric patients may struggle to access VMAT2 inhibitors due to insurance and financial barriers, lack of FDA approval in children, and potential side effects or medication interactions. Less is known about prescribing practices and patient experiences with VMAT2 inhibitors in the pediatric population.

We performed a retrospective chart review of patients treated with VMAT2 inhibitors at a pediatric movement disorders clinic from 2011 to 2023. Demographics, indication, medical history, and clinical notes were reviewed.

We identified 340 patients (65.3% male, average age 11.9 years) who had been prescribed a VMAT2 inhibitor. Of 347 prescriptions for VMAT2 inhibitors, 94% were prescribed tetrabenazine, 4.6% deutetrabenazine and 1.4% valbenazine. The clinical indication was mainly for the treatment of tics (73.5%), followed by chorea (9.1%) and stereotypy (7.1%). The majority of patients (62.8%) reported clinical improvement with an average Clinical Global Impression-Improvement of 1.8 (+/- 1.2). Some reported no improvement (11.5%) and others were unable to initiate (24.2%). 63.9% of patients reported side effects, most commonly drowsiness. Only 35 patients (10.1%) necessitated discontinuation due to adverse effects. Of the 347 prescriptions, 194 (59.3%) experienced at least one denial from insurance companies. 64 (19.6%) patients expressed financial concerns regarding medication affordability.

Our study suggests that VMAT2 inhibitors are effective and safe for treating pediatric hyperkinetic movement disorders. While adverse effects were common, most were mild and improved with dosage reduction or transitioning to deutetrabenazine or valbenazine. Furthermore, this study provides insight into barriers to pediatric access.