Narcolepsy Type 1Phase 2NCT07096674
A Long-term Extension Study of ORX750 in Participants With Narcolepsy and Idiopathic Hypersomnia
A Phase 2 study testing ORX750 in people with Narcolepsy Type 1 and Narcolepsy Type 2, run by Centessa Pharmaceuticals (UK) Limited at 24 sites in 4 countries.
Trial summary
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). Read more about this study
- Who is it for?
- Ages 18 to 65 years
- Conditions the study is for
- Narcolepsy Type 1, Narcolepsy Type 2, Idiopathic Hypersomnia
- What is being tested?
- ORX750
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 90 participants
- Where
- 24 sitesin 4 countries
- Study dates
- 12 Aug 2025to 30 Apr 2026
- Phase
- Phase 2
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 65 years
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Diagnosis of narcolepsy (NT1 or NT2) or IH who was eligible for and completed the full treatment period in the eligible parent study ORX750-0201 (CRYSTAL-1)
- Is willing and able to adhere to additional protocol requirements
Who cannot join
- Development of any new disease/disorder that in the opinion of the investigator would make the participant unable to continue the study
- Unable to refrain from excluded medications, including those used for treatment of narcolepsy or idiopathic hypersomnia
Trial locations and contacts
24 sites in 4 countries. Contact the study team or a site near you to ask about taking part.
24 sites in 4 countries
United States19 sites, 19 recruiting
- Recruiting
Abington, Pennsylvania
Abington, Pennsylvania, 19046
- Recruiting
Stockbridge, GA
Atlanta, Georgia, 30281
- Recruiting
Atlanta, Georgia
Atlanta, Georgia, 30328
- Recruiting
Auburn, alabama
Auburn, Alabama, 36832
- Recruiting
Austin, Texas
Austin, Texas, 30328
- Recruiting
Cincinnati, Ohio
Cincinnati, Ohio, 45245
- Recruiting
Denver, North Carolina
Denver, North Carolina, 28037
- Recruiting
Dublin
Dublin, Ohio, 43017
- Recruiting
El Paso, Texas
El Paso, Texas, 79912
- Recruiting
Hendersen, Navada
Henderson, Nevada, 89052
- Recruiting
Henderson, Nevada
Henderson, Nevada, 89052
- Recruiting
Huntersville, North Carolina
Huntersville, North Carolina, 28070
- Recruiting
Miami, Florida
Miami, Florida, 33176
- Recruiting
North Charleston, South Carolina
North Charleston, South Carolina, 29406-9196
- Recruiting
Orlando, Florida
Orlando, Florida, 32807
- Recruiting
Santa Ana, California
Santa Ana, California, 92705
- Recruiting
Sterling Heights, Michigan
Sterling Heights, Michigan, 48314
- Recruiting
Willow Grove, Pennsylvania
Willow Grove, Pennsylvania, 19090
- Recruiting
Winter Park, FL
Winter Park, Florida, 32789
Italy2 sites, 2 recruiting
- Recruiting
Bologna
Bologna, BO, 40139
- Recruiting
Verona
Verona, VR, 37134
Spain2 sites, 2 recruiting
- Recruiting
Álava, Spain
Álava, 01004
- Recruiting
Móstoles, Madrid
Móstoles, Madrid, 28938
About this study
Official title: A Phase 2, Long-term Extension Study of the Safety and Efficacy of ORX750 in Participants With Narcolepsy and Idiopathic Hypersomnia Who Completed a Sponsored ORX750 Clinical Trial
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).
- Conditions
- Narcolepsy Type 1, Narcolepsy Type 2, Idiopathic Hypersomnia
- Being tested
- ORX750
- Keywords
- NT1, NT2, IH, Narcolepsy, Narcolepsy Type 1, Narcolepsy Type 2, Idiopathic Hypersomnia, Excessive Daytime Sleepiness, Orexin Receptor 2 agonist
- Medical subject headings
- Idiopathic Hypersomnia, Narcolepsy, Disorders of Excessive Somnolence
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
ORX750Drug
Oral ORX750
ORX750Drug
Oral ORX750
ORX750Drug
Oral ORX750
| Study group | Role | What they receive |
|---|---|---|
| Narcolepsy Type 1 | Experimental | Narcolepsy Type 1 (Open Label) Receives: Drug: ORX750 |
| Narcolepsy Type 2 | Experimental | Narcolepsy Type 2 (Open Label) Receives: Drug: ORX750 |
| Idiopathic Hypersomnia | Experimental | Idiopathic Hypersomnia (Open Label) Receives: Drug: ORX750 |
What is being measured
The primary outcome is the main question the study is designed to answer.
Treatment Emergent Adverse Events (TEAEs) and Serious TEAEs
Number of Participants With Treatment Emergent Adverse Events (TEAEs) and Serious TEAEs
Measured: Up to day 70
Abnormal Laboratory Tests
Number of Participants With Abnormal Changes From Baseline in Laboratory Tests
Measured: Up to day 70
Abnormal Vital Signs
Number of Participants With Abnormal Change From Baseline in Vital Signs
Measured: Up to day 70
Abnormal ECG
Number of Participants With Abnormal Change From Baseline in Electrocardiograms (ECG)
Measured: 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)
Measured: Up to day 70
Secondary outcomes (7)
Cmax
Cmax: Maximum Observed Plasma Concentration for ORX750
Measured: Up to day 63
Tmax
Tmax: Time of Maximum Concentration for ORX750
Measured: 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
Measured: Up to day 63
Cmax,ss
Cmax,ss: Maximum Observed Concentration at Steady State for ORX750
Measured: Up to day 63
AUCτ
AUCτ: Area Under the Concentration-time Curve During a Dosing Interval at Steady State for ORX750
Measured: 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)
Measured: Up to day 63
Epworth Sleepiness Scale
Change From Baseline in Epworth Sleepiness Scale (ESS)
Measured: Up to day 63
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted31 Jul 2025
- Study start12 Aug 2025
- Primary completion30 Apr 2026 (estimated)
- Study completion30 Apr 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Narcolepsy Type 1Studies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 2
- Primary purpose
- Treatment
- Allocation
- Non-randomised
- Intervention model
- Single group
- Model description
- Open Label Long Term Extension Study
- Masking
- None (open label)
- Enrolment
- 90 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Centessa Pharmaceuticals (UK) Limited
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07096674
- Sponsor's protocol ID
- ORX750-202
- Status last verified
- Apr 2026
- First submitted
- 2 Jul 2025
- Last updated
- 16 Apr 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
Study at a glance
From the registry record, last updated by the sponsor on 16 Apr 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Phase 2, Long-term Extension Study of the Safety and Efficacy of ORX750 in Participants With Narcolepsy and Idiopathic Hypersomnia Who Completed a Sponsored ORX750 Clinical Trial
- ClinicalTrials.gov ID
- NCT07096674
- Acronym / sponsor ID
- ORX750-202
- Conditions
- Narcolepsy Type 1, Narcolepsy Type 2, Idiopathic Hypersomnia
- Keywords
- NT1, NT2, IH, Narcolepsy, Narcolepsy Type 1, Narcolepsy Type 2, Idiopathic Hypersomnia, Excessive Daytime Sleepiness
- Phase
- Phase 2
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 90 participants (estimated)
- Lead sponsor
- Centessa Pharmaceuticals (UK) LimitedIndustry (pharma, biotech, devices)
- Study start
- 12 Aug 2025 (actual)
- Primary completion
- 30 Apr 2026 (estimated)
- Study completion
- 30 Apr 2026 (estimated)
- First posted
- 31 Jul 2025 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
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).
Study design
- Primary purpose
- Treatment
- Allocation
- Non-randomised
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 3
- Model description
- Open Label Long Term Extension Study
| Arm | Type | Receives |
|---|---|---|
| Narcolepsy Type 1 | Experimental | Drug: ORX750Narcolepsy Type 1 (Open Label) |
| Narcolepsy Type 2 | Experimental | Drug: ORX750Narcolepsy Type 2 (Open Label) |
| Idiopathic Hypersomnia | Experimental | Drug: ORX750Idiopathic Hypersomnia (Open Label) |
Who may qualify
- Ages
- 18 to 65 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (2 listed)
- Diagnosis of narcolepsy (NT1 or NT2) or IH who was eligible for and completed the full treatment period in the eligible parent study ORX750-0201 (CRYSTAL-1)
- Is willing and able to adhere to additional protocol requirements
Key exclusion criteria (2 listed)
- Development of any new disease/disorder that in the opinion of the investigator would make the participant unable to continue the study
- Unable to refrain from excluded medications, including those used for treatment of narcolepsy or idiopathic hypersomnia
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| ORX750Oral ORX750 | Drug | Narcolepsy Type 1 |
| ORX750Oral ORX750 | Drug | Narcolepsy Type 2 |
| ORX750Oral ORX750 | Drug | Idiopathic Hypersomnia |
Primary outcome
Treatment Emergent Adverse Events (TEAEs) and Serious TEAEs
Time frame: Up to day 70
Number of Participants With Treatment Emergent Adverse Events (TEAEs) and Serious TEAEs
Abnormal Laboratory Tests
Time frame: Up to day 70
Number of Participants With Abnormal Changes From Baseline in Laboratory Tests
Abnormal Vital Signs
Time frame: Up to day 70
Number of Participants With Abnormal Change From Baseline in Vital Signs
Abnormal ECG
Time frame: Up to day 70
Number of Participants With Abnormal Change From Baseline in Electrocardiograms (ECG)
Suicidal Ideation or Behavior
Time frame: Up to day 70
Number of Participants With Suicidal Ideation or Suicidal Behavior as Measured Using Columbia-Suicide Severity Rating Scale (C-SSRS)
7 secondary outcomes
Cmax
Time frame: Up to day 63
Tmax
Time frame: Up to day 63
AUClast
Time frame: Up to day 63
Cmax,ss
Time frame: Up to day 63
AUCτ
Time frame: Up to day 63
Maintenance of Wakefulness Test
Time frame: Up to day 63
Epworth Sleepiness Scale
Time frame: Up to day 63
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 16 Apr 2026.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
24 sites in 4 countries: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 2 study testing ORX750 in people with Narcolepsy Type 1 and Narcolepsy Type 2, run by Centessa Pharmaceuticals (UK) Limited at 24 sites in 4 countries.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 2 inclusion and 2 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 16 Apr 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 24 sites in United States, Italy, Spain, Canada. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 2 studies give the treatment to a larger group to see whether it has the intended effect and to keep checking safety.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Orexin Centessa Program Lead (617-468-5770, ORX750-LTE@centessa.com), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Treatment Emergent Adverse Events (TEAEs) and Serious TEAEs (time frame: Up to day 70). The study lists 5 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 16 Apr 2026.