Real-World Antipsychotic and Vesicular Monoamine Transporter Type 2 Inhibitor Treatment Patterns in Patients Newly Diagnosed with Tardive Dyskinesia

Introduction Tardive dyskinesia (TD) is associated with antipsychotic (AP) use and management includes antipsychotic (AP) dose modification/discontinuation, often leaving underlying psychiatric conditions undertreated. Deutetrabenazine (DTBZ) is a vesicular monoamine transporter type 2 inhibitor (VMAT2i) approved to treat TD and Huntington disease– associated chorea. AP and VMAT2i treatment patterns post-TD diagnosis are unclear. Methods Patients aged ≥18 years, newly diagnosed with TD (July 2019– June 2022), with ≥1 AP and no VMAT2i claims pre-index were identified from the Symphony Health Solutions Integrated Dataverse (medical, hospital, and prescription claims across all US payer types). Patients were grouped into DTBZ (≥1 DTBZ claim within ≤6 months post-diagnosis) and non-VMAT2i groups, and further by stable DTBZ dose (for ≥60 days). The index date was the first DTBZ claim (DTBZ group) or the difference between TD diagnosis and first DTBZ claim (of the matched patient) added to TD diagnosis (non-VMAT2i group). Results Among 18,375 patients meeting inclusion criteria, 587 (3%) received DTBZ (292 stable-dose DTBZ), 676 (4%) received a different VMAT2i, and 17,112 (93%) had no VMAT2i claims. Among propensity score-matched patients with ≥1 AP claim pre- and post-index (326 DTBZ, 627 non-VMAT2i), pre-index mean AP proportions of days covered (PDCs) were similar between DTBZ (86%), stable-dose DTBZ (86%), and non-VMAT2i (83%) groups. Mean PDCs decreased post-index for DTBZ (86% to 85%) and non-VMAT2i (83% to 81%) groups, but increased for the stable-dose DTBZ group (86% to 88%). While these changes were small, post-index mean PDCs were significantly greater (versus non-VMAT2i) in the DTBZ (5% difference; P =.030) and stable-dose DTBZ (9%; P =.001) groups. Similar proportions of patients in the DTBZ (20%) and non-VMAT2i (20%) groups discontinued APs (ie, no AP claims within ≤6 months post-index). Proportions of patients with AP restarts (7%– 8%) and dose decreases (13%– 17%) were also similar between DTBZ, stable-dose DTBZ, and non-VMAT2i groups. Proportions of patients (16%– 18%) with AP dose increases were similar between DTBZ and non-VMAT2i groups, but significantly greater in the stable-dose DTBZ group (21%) vs non-VAMT2i ( P=. 02). Conclusions AP adherence was significantly, though not substantially, greater for DTBZ versus non-VMAT2i groups. These results suggest that DTBZ, when titrated to a stable/optimal dose, allows flexibility in treating underlying psychiatric conditions. Funding Teva Branded Pharmaceutical Products R&D, Inc.