TAK-861-3002
Recruitment Complete
A Study of TAK-861 in People With Narcolepsy Type 1
About this clinical trial
The main aim of this study is to learn how effective TAK-861 is in improving excessive sleepiness during the day (called excessive daytime sleepiness or EDS) after 3 months of treatment. Other aims are to learn how effective TAK-861 is in lowering the number of sudden, unexpected attacks of muscle weakness while staying conscious (cataplexy) in a week; to learn the effect TAK-861 has on participants' ability to maintain attention, participant's overall quality of life, the spectrum of narcolepsy symptoms and daily life functions; and to learn about the safety of TAK-861.
FR
BE
CN
8+
Interventional Phase 3 clinical trial.
At a glance
What medical conditions were being studied?
Narcolepsy Type 1
What was the clinical trial testing?
Placebo, TAK-861
How many participants were enrolled?
105
Were placebos part of the clinical trial?
Yes
When was the clinical trial conducted?
Nov 2024 - Jul 2025
How long was participation in the clinical trial?
Participants can stay in the study for up to 5.5 months (162 days).
Key requirements
Sexes
All
Age
16 to 70 Years
Healthy volunteers?
No
Entry criteria
Men and women can participate in this study.
Must be 16 to 70 years old, inclusive (regionally, 18 to 70 years old, per local regulations).
Diagnosed with Narcolepsy Type 1 (NT1).
Must have a minimum number of cataplexy attacks in a week.
Must have a body mass index (BMI) as defined by the study’s requirements.
Cannot have a medical condition (other than narcolepsy) linked to excessive sleepiness during the day.
Cannot have a history of cancer within the last 5 years.
Cannot have a history of certain brain conditions or a serious head injury.
Cannot have a history of heart attacks or certain other serious health conditions.
Cannot regularly go to sleep after midnight, work night shifts, or plan to travel with jet lag during the study.
Additional entry criteria will be discussed with the study doctor.
