0793 Nearly 25% of Restless Legs Syndrome (RLS) Patients Nationally Treated with Dopamine Agonists are Taking Higher Doses than the Maximum Recommended by FDA and Expert Guidelines

Abstract

Abstract Introduction Dopamine agonists (DAs) have been first-line therapy for restless legs syndrome (RLS) for 30 years. Long-term DA use is associated with augmentation, a dose-related iatrogenic worsening of RLS, which results in a vicious cycle of escalating DA dosing to manage worsening symptoms. The objective of this study was to investigate rates of high-dose DA prescribing in patients with RLS nationally. Methods Patients with a diagnosis of RLS (ICD-10 G255.81), and no diagnosis of Parkinson’s disease, treated with rotigotine, pramipexole, and ropinirole, alone or in combination for >180 days, were identified from National Prescription Audit database from October 2017-September 2018. Daily total dosage was grouped into low (FDA-approved) and high (above FDA-approved) dose ranges, respectively (rotigotine: >0-≤3mg/>3mg; pramipexole: >0-≤0.75mg/>0.75mg; ropinirole: >0-≤4mg/>4mg). When DAs were used in combination with each other, dose-equivalent algorithms were used (rotigotine/ropinirole/pramipexole, 1:1:4). Results Prescriptions for 244,423 patients meeting inclusion criteria were sampled, constituting 71,181,466 therapy days. For all patients on DA therapy for RLS, 23.5% (57,552/244,423) were prescribed higher than FDA-recommended doses. For patients on DA monotherapy, high-dose prescriptions were provided to 42.7% (819/1919) on rotigotine, 40.7% (38,342/94,275) on pramipexole, and 11.5% (16,900/146,355) on ropinirole. Nearly one-quarter (23.2%) of all pramipexole monotherapy prescriptions were for very high dosages (>1.25 mg). For patients on DA combination therapy, high-dose prescriptions were provided to 79.6% (1,491/1,874). Conclusion Roughly 25% of RLS patients treated with DAs were prescribed doses above FDA and expert guideline-recommended maximum doses. Patients on DA combination therapy had substantially higher rates of cumulative high-dose prescriptions. High-dosage DA use is likely due to dose escalation in response to augmentation, risking further augmentation and adverse events such as impulse control disorders. Prescriber education on risks of high-dose DA prescribing for RLS is important. Support Arbor Pharmaceuticals, LLC