A Phase 2 interventional study of ORX750 and ORX750 in Narcolepsy Type 1, Narcolepsy Type 2 and Idiopathic Hypersomnia, sponsored by Centessa Pharmaceuticals (UK) Limited. Recruiting at 24 sites in 4 countries. Open to participants aged 18 Years to 65 Years. Per ClinicalTrials.gov, last updated 2026-04-16.
Sponsored by Centessa Pharmaceuticals (UK) Limited · Phase 2, Interventional, and Treatment
This study is a long-term extension (LTE) of the parent Study ORX750 0201, and will provide long-term open-label safety, tolerability, and efficacy of ORX750 in participants with narcolepsy type 1 (NT1), narcolepsy type 2 (NT2), and idiopathic hypersomnia (IH).
52 studies on the registry are indexed under Idiopathic Hypersomnia; 23 are open to participants now.
This study's planned enrollment of 90 is close to the median of 82 across 40 interventional studies indexed under Idiopathic Hypersomnia.
Browse Idiopathic Hypersomnia studies →Centessa Pharmaceuticals (UK) Limited is the lead sponsor of 6 studies on the registry; 5 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Narcolepsy Type 1 (Open Label)
Drug: ORX750
Narcolepsy Type 2 (Open Label)
Drug: ORX750
Idiopathic Hypersomnia (Open Label)
Drug: ORX750
Oral ORX750
Oral ORX750
Oral ORX750
Treatment Emergent Adverse Events (TEAEs) and Serious TEAEs
Number of Participants With Treatment Emergent Adverse Events (TEAEs) and Serious TEAEs
Time frame: Up to day 70
Abnormal Laboratory Tests
Number of Participants With Abnormal Changes From Baseline in Laboratory Tests
Time frame: Up to day 70
Abnormal Vital Signs
Number of Participants With Abnormal Change From Baseline in Vital Signs
Time frame: Up to day 70
Abnormal ECG
Number of Participants With Abnormal Change From Baseline in Electrocardiograms (ECG)
Time frame: Up to day 70
Suicidal Ideation or Behavior
Number of Participants With Suicidal Ideation or Suicidal Behavior as Measured Using Columbia-Suicide Severity Rating Scale (C-SSRS)
Time frame: Up to day 70
Cmax
Cmax: Maximum Observed Plasma Concentration for ORX750
Time frame: Up to day 63
Tmax
Tmax: Time of Maximum Concentration for ORX750
Time frame: Up to day 63
AUClast
AUClast: Area Under the Plasma Concentration-time Curve From Time 0 to the Time of the Last Quantifiable Concentration for ORX750
Time frame: Up to day 63
Cmax,ss
Cmax,ss: Maximum Observed Concentration at Steady State for ORX750
Time frame: Up to day 63
AUCτ
AUCτ: Area Under the Concentration-time Curve During a Dosing Interval at Steady State for ORX750
Time frame: Up to day 63
Maintenance of Wakefulness Test
Change From Baseline in Mean sleep latency (average of the first 4 trials) in the Maintenance of Wakefulness Test (MWT)
Time frame: Up to day 63
Epworth Sleepiness Scale
Change From Baseline in Epworth Sleepiness Scale (ESS)
Time frame: Up to day 63
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Centessa Pharmaceuticals (UK) Limited