Trial results
AI generated results summary. Written by an AI model from the official source data and checked on a sample basis. It can contain mistakes, so confirm anything important against the original source. How we use AI
According to the results reported on ClinicalTrials.gov, this trial (NCT05687916) enrolled 71 people in total, split across three groups: 24 received a placebo (a dummy treatment), 23 received a dose of TAK-861 called "2 mg BID" (meaning twice a day), and 24 received a varying dose of TAK-861 (starting at 2 mg and moving to 5 mg). The trial was measuring how well participants could stay awake, using a standard test called the Maintenance of Wakefulness Test (MWT), which records brain activity to track how long someone can resist falling asleep during 40-minute rest sessions. It also measured how sleepy participants felt during daily life using a self-rated questionnaire called the Epworth Sleepiness Scale (ESS), where higher scores mean greater daytime sleepiness. The reported data shows that, after 8 weeks, the average improvement in the time participants could stay awake (compared to their starting point) was 2.14 minutes for the placebo group, 1.90 minutes for the fixed 2 mg twice-daily group, and 4.54 minutes for the group whose dose was adjusted up to 5 mg. On the sleepiness questionnaire — scored from 0 to 24 — the reported average reduction in score (lower scores meaning less sleepiness) was 3.39 points for the placebo group, 3.71 points for the fixed 2 mg group, and 6.45 points for the dose-adjusted group. The reported data also shows how many participants in each group experienced at least one adverse event (an unintended medical occurrence during the study): 8 out of 24 in the placebo group, 10 out of 23 in the fixed 2 mg group, and 18 out of 24 in the dose-adjusted group. The trial did not report further detail on what those events were within this dataset. These are the results as reported to ClinicalTrials.gov. They are not medical advice — always discuss what they mean for you with your doctor.
View full results on ClinicalTrials.gov ↗
These are the results as reported to ClinicalTrials.gov, not medical advice. Verify independently with the trial site and discuss what they mean for you with your doctor.
Phase 2 Narcolepsy Trial, Completed
Who may be able to join
AI generated eligibility summary. Written by an AI model from the official source data and checked on a sample basis. It can contain mistakes, so confirm anything important against the original source. How we use AI
Who might be able to join this trial:
- You are between 18 and 70 years old at the time of signing the consent form (in Japan, ages 16 to 70 may be included).
- You have been officially diagnosed with Type 2 Narcolepsy (narcolepsy without cataplexy), confirmed by specific sleep studies (overnight sleep test and daytime nap test) done within the past 5 years — if your tests were done longer ago or are unavailable, the trial site may be able to repeat them.
Who may not be able to join:
- You have a medical condition other than Type 2 Narcolepsy that causes excessive daytime sleepiness.
- You have a personal history of epilepsy, seizures, or convulsions, or a family history of inherited conditions linked to seizures (a single childhood fever-related seizure may be an exception — confirm with trial site).
- You currently have, or have a history of, certain mental health conditions, including unstable psychiatric disorders, bipolar disorder, schizophrenia or other psychotic disorders, obsessive compulsive disorder, or major depression with psychotic features.
- You have had a current or recent active episode of major depression within the past 6 months.
- You have a current or past substance use disorder — though if it was more than 12 months ago, you may still be considered after discussion with the trial team (confirm with trial site).
- You have a history of stroke, a recent mini-stroke (within the last 5 years), a brain aneurysm, or an abnormal tangle of blood vessels in the brain.
- You had major surgery, or lost or donated roughly a pint of blood (about 500 mL), within the 4 weeks before your screening visit.
Important: Always verify eligibility with the trial site directly before applying.
Based on publicly available eligibility criteria from ClinicalTrials.gov. Verify directly with the trial site before acting. This is not medical advice.
Contact this trial
Principal Investigator: Medical Director, Takeda
Australian sites
Contact details sourced from ClinicalTrials.gov. Verify directly with the trial site before attending.
GP referral letter
Print a one-page summary to share with your doctor.
Trial details
Where this trial is recruiting
1 site(s) in Australia. Confirm current status and contact details directly with the trial site.
Primary endpoints
Change From Baseline in the Average Sleep Latency as Determined From the MWT at Week 8
Can't join this trial?
Data last synced from ClinicalTrials.gov: 28 July 2026. Trial status can change. Always verify current status directly with the trial site before making any decision.