What are the indications and eligibility criteria for the Nidra (Tonic Motor Activation) implant in adults with moderate-to-severe Restless Legs Syndrome refractory to standard pharmacologic therapy?

Indications for NIDRA (TOMAC) Implant

The NIDRA system (Tonic Motor Activation/TOMAC) is indicated for adults with moderate-to-severe primary restless legs syndrome (RLS) who have failed standard pharmacological therapy, particularly those refractory to first-line treatments including gabapentinoids and IV iron.

Primary Indication

The device is specifically designed for medication-refractory RLS patients 1. According to the most recent 2025 AASM guidelines, bilateral high-frequency peroneal nerve stimulation (the mechanism of TOMAC) is conditionally recommended for adults with RLS 1.

Eligibility Criteria

Patient Population

• Adults with moderate-to-severe primary RLS who meet diagnostic criteria
• Refractory to standard pharmacological therapy, defined as:
  • Failed trials of first-line agents (gabapentin, pregabalin, or IV iron formulations) 1
  • Inadequate response to or intolerance of these medications
  • Average refractoriness to 3+ prior medications in clinical trials 2, 3

Clinical Characteristics

• Patients experiencing chronic sleep disturbances from RLS symptoms
• Those with documented treatment failure with gabapentinoids (strong AASM recommendation for these as first-line) 1
• Patients who have had appropriate iron status evaluated and optimized (ferritin and transferrin saturation) 1

Special Populations

• Medication-resistant patients who cannot achieve symptom control with available drugs 2, 4
• Medication-naïve patients who are unwilling or unable to take medications 4
• Patients on chronic opioid therapy for RLS who need dose reduction to minimize risks 3

Treatment Algorithm Position

Step 1: Optimize iron status first (ferritin, transferrin saturation) and treat with IV iron if appropriate 1

Step 2: Trial of gabapentin or pregabalin (strong AASM recommendations) 1

Step 3: If refractory, consider TOMAC/peroneal nerve stimulation as a non-pharmacological alternative 1

Step 4: Reserve opioids for truly refractory cases, potentially combined with TOMAC to enable dose reduction 3

Evidence Base

The RESTFUL trial demonstrated 45% CGI-I responder rate versus 16% for sham (p=0.00011) at 4 weeks 2. Long-term data showed sustained efficacy with 72.7% responder rate at 24 weeks 5. The device enabled 29.9% opioid dose reduction in patients on chronic opioid therapy without worsening RLS symptoms 3.

Key Advantages for Refractory Patients

• Non-pharmacological approach avoiding medication side effects and augmentation risk (major concern with dopamine agonists that AASM now recommends against) 1
• No serious device-related adverse events in clinical trials; most AEs were mild discomfort or site irritation that resolved rapidly 2, 5
• Self-administered at home when symptoms present, providing on-demand relief 2, 3
• Enables opioid reduction in patients requiring chronic opioid therapy 3

Important Caveats

• The AASM recommendation is conditional with moderate certainty of evidence 1, reflecting that this is a newer therapy with less long-term data than medications
• Benefits partially revert upon cessation of treatment, indicating need for ongoing use 5
• Most effective when used as part of comprehensive RLS management after optimizing iron status and attempting first-line pharmacotherapy 1
• Not a replacement for addressing secondary causes of RLS (iron deficiency, renal failure, medication-induced) 1