A Phase 3 interventional study of Tasimelteon Oral Suspension and Placebo in Insomnia Disorder, sponsored by Vanda Pharmaceuticals. Recruiting at 35 sites in 4 countries. Open to participants aged 2 Years to 17 Years. Per ClinicalTrials.gov, last updated 2026-06-05.
Sponsored by Vanda Pharmaceuticals · Phase 3, Interventional, and Treatment
This is a multicenter, double-blind, randomized study to evaluate the efficacy and safety of a daily single oral dose of tasimelteon and matching placebo in male and female pediatric participants with insomnia disorder.
2,722 studies on the registry are indexed under Sleep Initiation and Maintenance Disorders; 726 are open to participants now.
This study's planned enrollment of 420 is above the median of 68 across 2,350 interventional studies indexed under Sleep Initiation and Maintenance Disorders.
Browse Sleep Initiation and Maintenance Disorders studies →Vanda Pharmaceuticals is the lead sponsor of 82 studies on the registry; 17 are open to participants now.
Of its 33 completed or terminated interventional studies of FDA-regulated products, 22 (67%) have results posted.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Drug: Tasimelteon Oral Suspension
Drug: Placebo
Single daily dose, weight-based liquid suspension formulation.
Placebo comparator.
Change in sleep latency, as measured by daily sleep diary.
Time frame: 12 Weeks
Change in nighttime subjective sleep parameters, such as sleep quality, as measured by sleep diary.
Time frame: 12 Weeks
Change in nighttime subjective sleep parameters, such as sleep time, as measured by sleep diary.
Time frame: 12 Weeks
Change in daytime functioning, as measured by questionnaire.
Time frame: 12 Weeks
Change in behavior, as measured by questionnaire.
Time frame: 12 Weeks
Change in nighttime objective sleep parameters such as sleep time, as measured by actigraphy.
Time frame: 12 Weeks
Assessment of safety and tolerability of daily single dose of tasimelteon, as measured by spontaneous reporting of adverse events (AEs).
Time frame: 12 Weeks
Not enrolling at this site — choose another above.
Plan to share: No
No publications or documents are linked to this record.
Started Apr 2025 (actual). Primary completion is estimated for Nov 2027, 31 months after the start.
Of 29 industry-sponsored phase 3 interventional studies under Sleep Initiation and Maintenance Disorders, half reached primary completion within 18 months of starting (the median), counting those still running; a quarter within 9 and three quarters within 25. This study's planned 31 months is above that.
Counting every sponsor, half of 42 studies reached it within 19 months; a quarter within 15 and three quarters within 28.
How these figures are worked out, and which studies are left out of them.
Eligibility is decided by the study team. Share this record with your doctor or contact the team directly.
Contact study teamGet an email when the registry record changes — status, dates, results — or when someone posts here.
Sign in to followQuestions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.
Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.
Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.
Studies of the drug tested here: Tasimelteon
Sleep Initiation and Maintenance Disorders →