Clinical Trial 43865

Atlanta, GA 30328


The purpose of this study is to assess the safety and tolerability of TAK-994 following multiple oral doses in participants with narcolepsy with or without cataplexy (NT1 or NT2).


Inclusion Criteria:

  1. Has a diagnosis of narcolepsy type 1 (NT1) (Cohorts 1-4) or NT2 (Cohorts 5-6) by polysomnography (PSG)/ multiple sleep latency test (MSLT) performed within the past 10 years meeting the minimal acceptable criteria for the proper performance of the PSG/MSLT as outlined by the International Classification of Sleep Disorders, 3rd edition criteria.
  2. The participant's Epworth Sleepiness Scale (ESS) score must be greater than or equal to (>=) 10 at Day -1.
  3. Must be willing to discontinue all medications used for the treatment of NT1/NT2.
  4. Must have human leukocyte antigen (HLA) genotype test positive for HLA DQB1*06:02 (Cohorts 1-4).
  5. Must have >=4 partial or complete episodes of cataplexy/weekby history when off of anticataplexy medications and >=4 partial or complete episodes of cataplexy/week during the screening period when off of anticataplexy medications, averaged over 2 weeks minimum, with a >=80 percent (%) compliance rate in completion of the self-reported electronic diary for cataplexy episodes (Cohorts 1-4).

Exclusion Criteria:

  1. Has a risk of suicide according to endorsement of Item 4 or 5 of the screening/baseline visit Columbia suicide severity rating scale (C-SSRS) or has made a suicide attempt in the previous 12 months.
  2. Is an excessive (>600 mg/day) caffeine user 1 week prior to the study screening.
  3. Has a history of cancer (except carcinoma in situ that has been resolved without further treatment or basal cell skin cancer); past or current epilepsy, seizure; a lifetime history of major psychiatric disorder other than depression or anxiety; a clinically significant history of head injury or head trauma; a history of cerebral ischemia, transient ischemic attack, intracranial aneurysm, or arteriovenous malformation; known coronary artery disease, a history of myocardial infarction, angina, cardiac rhythm abnormality, or heart failure; or current or recent (within 6 months) gastrointestinal disease expected to influence the absorption of drugs.
  4. Used any product with stimulating or sedating properties within 7 days or 5 times the elimination half-lives (whichever is greater) prior to dosing.
  5. Has a medical disorder (including moderate to severe sleep apnea syndrome), other than narcolepsy, associated with excessive daytime sleepiness or has any other medical condition (e.g, anxiety, depression, epilepsy, heart disease, or significant hepatic, pulmonary, or renal disease) that requires the participant to take excluded medications.
  6. Has a usual bedtime later than 2400 (12:00 AM, midnight) or an occupation requiring nighttime shift work or variable shift work within the past 6 months or travel with significant jet lag within 14 days before Study Day -2.
  7. Has a nicotine dependence that is likely to have an effect on sleep (e.g., a participant who routinely awakens at night to smoke) and/or an unwillingness to discontinue all smoking and nicotine use during the confinement portions of the study.

    Participants undergoing optional CSF collection (Cohorts 1-3 and 5-6 only).

  8. Has a local infection at the puncture site.
  9. Has developed signs of lumbar radiculopathy, including lower extremity pain and paresthesia.
  10. Has any known focal neurological deficit that might suggest an increase in intracranial pressure.

Qualified Participants May Receive:

Compensation for time and travel for all completed study visits.

Clinical trials are medical research studies designed to test the safety and/or effectiveness of new investigational drugs, devices, or treatments in humans. These studies are conducted worldwide for a range of conditions and illnesses. Learn more about clinical research and participating in a study at About Clinical Trials.