Efficacy of Melatonin, Low-dose Quetiapine, or Placebo in Patients With Psychiatric Disorders and Comorbid Insomnia

Efficacy of Melatonin, Low-dose Quetiapine, or Placebo in Patients With Psychiatric Disorders and Comorbid Insomnia: a Randomized Clinical Trial

The goal of this investigator-initiated, randomized, blinded, 3-armed placebo-controlled, pragmatic, clinical superiority trial is to examine the efficacy of melatonin or low-dose quetiapine versus placebo for treatment of insomnia in patients with psychiatric disorders. The aims of the study are:

• To examine the efficacy of melatonin or low-dose quetiapine versus placebo for treatment of insomnia
• To examine how melatonin or low-dose quetiapine affects global symptom severity, sleep quality, psychosocial functioning and subjective well-being.

Participants will receive six weeks of treatment with either melatonin, quetiapine or placebo followed by a brief taper off.

Inclusion Criteria:

• 16 to 64 years of age
• ICD-10 diagnosis of a current or previous mental or behavioral disorder (F20-F69, F84, F90-95)
• For the diagnoses F84 and F90 a previous period of treatment with melatonin is required
• For the 16-17 years old: Non-pharmacological treatment options including sleep hygiene education, weighted blanket or other gravity products have been tested with insufficient effect
• Self-reported sleep difficulties at least three times per week in the preceding 3 months
• Insomnia Severity Index score ≥11
• Women of childbearing potential: negative pregnancy test at baseline and use of highly effective contraception measures
• Informed consent

Exclusion Criteria:

• Current treatment with melatonin or quetiapine
• Severe somatic comorbidity
• BMI ≥ 35 kg/m2
• Breastfeeding
• Alcohol and/or substance dependency within the last 3 months
• Inadequate Danish language skills
• Not able to make an informed consent
• Increased cardiac risk as assessed by presence of cardiac risk factors, cardiac symptoms, or prolonged QT-interval at baseline ECG