A Study of ORX142 in Healthy Adult Subjects, Including Subjects 18 to 80 Years of Age

• ORX142 Tablets (Drug): ORX142 Tablets
• Placebo Tablets (Other): Placebo Tablets

Primary outcomes

• Part A: Incidence and severity of Treatment-Emergent Adverse Events of oral single ascending doses of ORX142 in healthy adult subjects [From enrollment to the Follow-Up Visit 13 days post-discharge]: Safety and Tolerability as assessed by AEs and SAEs
• Part B: Incidence and severity of Treatment-Emergent Adverse Events of oral single ascending doses of ORX142 in the fasted and fed states [From enrollment to the Follow-Up Visit 13 days post-discharge]: Safety and Tolerability as assessed by AEs and SAEs
• Part C: Incidence and severity of Treatment-Emergent Adverse Events of oral multiple ascending doses of ORX142 in healthy adult subjects [From enrollment to the Follow-Up Visit 13 days post-discharge]: Safety and Tolerability as assessed by AEs and SAEs
• Part D: Incidence and severity of Treatment-Emergent Adverse Events of oral single oral doses of ORX142 in healthy older adult subjects [From enrollment to the Follow-Up Visit 13 days post-discharge]: Safety and Tolerability as assessed by AEs and SAEs
• Part E: Incidence and severity of Treatment-Emergent Adverse Events of oral of single oral doses of ORX142 in acutely sleep-deprived healthy adult subjects [From enrollment to the Follow-Up Visit 13 days post-discharge]: Safety and Tolerability as assessed by AEs and SAEs

Secondary outcomes

• Cmax: Maximum Observed Plasma Concentration for ORX142 in subjects receiving ORX142 [Pre-dose and multiple post-dose timepoints, up to 48 hours]
• Tmax: Time of Maximum Concentration for ORX142 in subjects receiving ORX142 [Pre-dose and multiple post-dose timepoints, up to 48 hours]
• AUClast: Area Under the Plasma Concentration-time Curve From Time 0 to the Time of the Last Quantifiable Concentration for ORX142 in subjects receiving ORX142 [Pre-dose and multiple post-dose timepoints, up to 48 hours]
• T 1/2 (terminal elimination half-life): The time required for the terminal phase blood concentration of ORX142 to decrease by half in subjects receiving ORX142 [Pre-dose and multiple post-dose timepoints, up to 48 hours]
• Cmax: Maximum Observed Plasma Concentration for ORX142 in subjects receiving ORX142 in the fasted and fed state. [Pre-dose and multiple post-dose timepoints, up to 48 hours]
• Tmax: Time of Maximum Concentration for ORX142 in subjects receiving ORX142 in the fast and fed state [Pre-dose and multiple post-dose timepoints, up to 48 hours]
• AUClast: Area Under the Plasma Concentration-time Curve From Time 0 to the Time of the Last Quantifiable Concentration for ORX142 in subjects receiving ORX142 in the fast and fed state [Pre-dose and multiple post-dose timepoints, up to 48 hours]
• T 1/2 (terminal elimination half-life): The time required for the terminal phase blood concentration of ORX142 to decrease by half in subjects receiving ORX142 in the fast and fed state [Pre-dose and multiple post-dose timepoints, up to 48 hours]
• Mean sleep latency in the Maintenance of Wakefulness Test (MWT) for ORX142 versus placebo. [Part E: Day 2]
• Karolinska Sleepiness Scale score for ORX142 versus placebo [Part E: Day 1-2]

Sex: All, ages: 18 Years to 80 Years, accepts healthy volunteers

Key Inclusion Criteria:

1. Healthy males or females as determined by assessments at the Screening Visit.

   For Parts A, B, C, and E:

   a. Participants must be at least 18 years of age and no more than 55 years of age at the Screening
2. For Part D:

a .Participants must be at least 60 years of age and no more than 80 years of age at the Screening

Key Exclusion Criteria:

1. Presence of significant cardiac, pulmonary, gastrointestinal, hepatic, renal, hematological, malignancy, endocrine, neurological, or psychiatric disease, as determined by medical history, physical examination, and screening investigations.
2. History of seizure disorder, any other condition that increases the risk of seizure
3. Has a clinically significant sleep disorder, including insomnia or sleep apnea.