Study to Evaluate the Abuse Potential of ACT-541468 in Healthy Recreational Drug Users

Inclusion criteria

• Signed informed consent prior to any study-mandated procedure
• Male or female healthy subjects, 18-55 years of age (inclusive) at Screening
• Body mass index of 18.0-33.0 kg/m2 (inclusive) at Screening and a minimum weight of 50.0 kg at Screening
• Current sedative users who have used sedatives (e.g., benzodiazepines, zolpidem, eszopiclone, gamma-hydroxybutyrate, barbiturates) for recreational (non-therapeutic) purposes (i.e., for psychoactive effects) at least ten times in their life and at least once in the 12 weeks before Screening
• Women of childbearing potential must consistently and correctly use a reliable method of contraception with a failure rate of < 1% per year, be sexually inactive, or have a vasectomized partner
• Women of non-childbearing potential
• Male subjects are required to use a medically acceptable method of contraception throughout the entire study period and for at least 90 days after last study drug administration

Exclusion criteria

• History of major medical or surgical disorders which, in the opinion of the investigator, are likely to interfere with the absorption, distribution, metabolism, or excretion of the study treatment(s)
• Positive HIV or hepatitis B/C test at Screening
• Female subjects who are currently pregnant or lactating or who are planning to become pregnant within 1 month of the last study treatment administration
• Modified Swiss Narcolepsy Scale total score < 0 at Screening or history of narcolepsy or cataplexy
• Substance or alcohol dependence within 2 years prior to Screening or prior participation in a substance or alcohol dependence rehabilitation program
• Subjects who have a positive urine drug screen at admittance to the qualification or core phase
• Any sleep-disorder including self-reported insomnia disorder, breathing-related sleep disorders, restless legs syndrome (RLS), nightmare disorder, non-rapid eye movement (REM), sleep arousal disorders, REM sleep behavior disorder, circadian rhythm sleep-wake disorders, or narcolepsy
• Any of the following SLEEP-50 Questionnaire scores at Screening:

• ≥ 15 on Apnea subscale;
• ≥ 7 on Narcolepsy subscale;
• ≥ 7 on RLS or Periodic limb movement disorder subscale;
• ≥ 8 on Circadian Rhythm subscale;
• ≥ 7 on Sleepwalking subscale;
• ≥ 3 on Item 32 and ≥ 9 on Items 33 to 35 (i.e., on nightmare subscale);
• ≥ 15 on Impact subscale.
• Any circumstances or conditions, which, in the opinion of the investigator, may affect full participation in the study or compliance with the protocol