Efficacy of Suvorexant in Patients With Effectively Treated Restless Legs Syndrome and Persistent Chronic Insomnia
Condition: Restless Legs Syndrome; Insomnia; Sleep Disorder
MeSH terms: Sleep Initiation and Maintenance Disorders; Sleep Wake Disorders; Psychomotor Agitation; Restless Legs Syndrome; Syndrome
Intervention: Suvorexant; Placebo
Intervention description: 10-mg or 20-mg suvorexant capsules; Matching placebo capsules
Intervention MeSH terms: Suvorexant
Phase: Phase 4
Study type: Interventional
Primary purpose: Treatment
Allocation: Randomized
Intervention model: Crossover Assignment
Intervention model description: Subjects will be randomized in a 1:1 ratio to suvorexant 10-20 mg or equivalent placebo for four weeks followed by crossover (after a 2-week washout) to the alternate treatment.
Masking: Double (Participant, Investigator)
Masking description: The participant, investigator, and clinical research coordinator will remain masked throughout the duration of the study.
Enrollment: 46.0
Sex: All
Minimum age: 25 Years
Maximum age: 85 Years
Healthy volunteers: No
Keywords: Suvorexant

Summary:

      The investigators aim to determine the effect of suvorexant on actigraphically-derived total
      sleep time in patients with effectively treated restless legs syndrome with persistent
      insomnia in a two-arm, double-blind, randomized placebo-controlled crossover 2.5-month trial.
    

Eligibility criteria:

        Inclusion Criteria:

          1. Men or women of any ethnic origin

          2. Written informed consent is obtained

          3. Speaks and writes in English

          4. A willingness and ability to comply with study procedures

          5. Age 25-85 years

          6. Diagnosis of RLS via Cambridge-Hopkins RLS questionnaire

          7. International Restless Legs Syndrome Study Group scale score (IRLS) < 15

          8. RLS treatment with a dopaminergic agonist or an alpha-2-delta agent

          9. No changes in RLS medication in the previous month

         10. DSM-5 criteria for Insomnia Disorder

         11. Report a total sleep time ≤ 7 hours and wake after sleep onset (WASO) > 45 minutes on
             7 or more of the 14 nightly sleep logs during both the initial 2-week screening period
             and the two-week screening run-in period. WASO does not decrease by more than 50% on
             the 2-week sleep diary obtained between the screening visit and the randomization
             visit

        Exclusion Criteria:

          1. Diagnosis of moderate/severe obstructive sleep apnea (AHI > 30) not using continuous
             positive airway pressure therapy (CPAP) (can be included if CPAP adherent), or other
             untreated primary sleep disorders (e.g. narcolepsy)

          2. Shift workers

          3. Unwillingness to not use sedative-hypnotics (other than suvorexant) during the study
             period

          4. Unwillingness to maintain stable RLS medication during the study unless medically
             indicated

          5. Current use of an opiate medication

          6. Unwillingness to not take stimulants (e.g. caffeine) after 4:00 pm during the study

          7. Current major depressive episode, by report and as indicated by the Patient Health
             Questionnaire (PHQ-9)

          8. Lifetime history of bipolar disorder, psychosis, or other serious psychiatric illness

          9. Current alcohol/substance use disorder

         10. BMI ≥ 40 kg/m^2

         11. Renal or hepatic disease judged to interfere with drug metabolism and excretion

         12. Pregnancy or breastfeeding

         13. Malignancy within past 2 years

         14. Surgery within past 3 months

         15. Neurological disorder or cardiovascular disease raising safety concerns about use of
             suvorexant and/or judged to interfere with ability to assess efficacy of the treatment

         16. Medical instability considered to interfere with study procedures

         17. Concomitant medications with drug interaction or co-administration concerns

         18. Contraindications or allergic responses to suvorexant

         19. History of being treated with suvorexant

         20. Travel across two time-zones during the week prior to enrollment

         21. Greater than 6 cups of coffee per day