0781 Comparative Response to Tonic Motor Activation (TOMAC) and Extended-Duration TOMAC for Restless Legs Syndrome (RLS)

Abstract Introduction Restless legs syndrome (RLS) is often associated with breakthrough symptoms during sleep causing increased wake after sleep onset. High-frequency peroneal nerve stimulation – also known as tonic motor activation (TOMAC) – reduces RLS symptoms and improves sleep when administered for 30-minutes as needed (TOMAC-30). Here, we evaluated comparative response to an investigational device that stimulates for an extended duration of 180-minutes every night (TOMAC-180). Methods This open-label trial enrolled patients with moderate-to-severe RLS (IRLS ≥15) who reported ≥3 nights per week of mid-night awakenings with symptoms. Patients were assigned to TOMAC-30 for two weeks followed by six weeks of TOMAC-180. For TOMAC-30, patients activated 30-minute sessions as needed at bedtime or after mid-night awakenings. For TOMAC-180, patients activated one 180-minute session every night. Outcome measures were evaluated at week-8 relative to study entry and were International RLS Study Group Rating Scale (IRLS) score, Medical Outcomes Study Sleep Problems Index II (MOS-II), and Patient Global Impressions of Improvement (PGI-I) responder rate. All week-8 outcomes for participants in the present study (n=14) were compared to week-8 outcomes for participants who were assigned to TOMAC-30 (not sham) in the previously published RESTFUL study (n=64). Results Mean IRLS change for TOMAC-180 was −11.4 points (CI: −15.4, −7.3) versus −8.7 for TOMAC-30 in RESTFUL (CI: −10.2, −7.1), a difference of −2.7 (CI: −7.0, 1.6). The prevalence of ≥10 point IRLS reduction was 71.4% for TOMAC-180 versus 35.9% for TOMAC-30 in RESTFUL. Mean MOS-II change was −30.7 points (CI: −42.0, −19.3) for TOMAC-180 versus −18.2 for TOMAC-30 in RESTFUL (CI: −21.8, −14.5), a difference of −12.5 (CI: −24.3, −0.8). PGI-I responder rate was 78.6% for TOMAC-180 and 60.9% for TOMAC-30 in RESTFUL. No device-related serious or severe adverse events were observed, and no patients discontinued TOMAC-180 due to adverse events or lack of tolerability. Conclusion Extending the duration of TOMAC stimulation during sleep from 30 to 180 minutes was well tolerated and may lead to greater improvements in RLS symptoms and sleep, especially for patients with frequent awakenings. Further research with a larger sample size and randomized control group is warranted. Support (if any) This study was funded by Noctrix Health, Inc.