UMIN-ICDS Clinical Trial

Public title

Association Between Vornorexant Use and CPAP Adherence in Patients With Comorbid Insomnia and Obstructive Sleep Apnea

Acronym

Vornorexant-COMISA Study

Scientific Title

Association Between Vornorexant Use at CPAP Initiation and CPAP Adherence in Patients With Comorbid Insomnia and Obstructive Sleep Apnea: A Prospective Observational Cohort Study

Scientific Title:Acronym

Vornorexant-COMISA Study

Region

Japan

Condition

Comorbid insomnia and obstructive sleep apnea (COMISA)

Classification by specialty

Pneumology

Oto-rhino-laryngology

Classification by malignancy

Others

Genomic information

NO

Narrative objectives1

The aim of this prospective observational cohort study is to investigate the association between vornorexant use, prescribed as part of routine clinical care at the initiation of continuous positive airway pressure (CPAP) therapy, and CPAP adherence in patients with comorbid insomnia and obstructive sleep apnea (COMISA). Patients prescribed vornorexant will be compared with those not prescribed vornorexant in terms of mean nightly CPAP usage over the first 90 days and changes in Athens Insomnia Scale (AIS) scores at one month after CPAP initiation.

Basic objectives2

Others

Basic objectives -Others

A prospective observational study evaluating the association of vornorexant prescription in routine clinical practice with CPAP adherence and changes in insomnia symptoms after CPAP initiation. No treatment is assigned for research purposes.

Trial characteristics_1

Exploratory

Trial characteristics_2

Pragmatic

Developmental phase

Not applicable

Primary outcomes

Mean nightly CPAP usage (hours/night) during the first 90 days after CPAP initiation, measured using objective CPAP device data and compared between the vornorexant prescription and non-prescription groups.

Change in Athens Insomnia Scale (AIS) score from baseline to 1 month after CPAP initiation, compared between the two groups.

Key secondary outcomes

1. Mean nightly CPAP usage during the first 30, 90, and 180 days after CPAP initiation.
2. Percentage of nights with CPAP use and percentage of nights with at least 4 hours of CPAP use, assessed over the first 30, 90, and 180 days.
3. CPAP discontinuation and dropout status at 1, 3, and 6 months.
4. Residual apnea-hypopnea index (AHI), mask leak, and other CPAP device data at 1, 3, and 6 months.
5. Changes in Athens Insomnia Scale (AIS) scores from baseline to 1, 3, and 6 months.
6. Changes in Karolinska Sleepiness Scale (KSS) and other questionnaire scores from baseline to 1, 3, and 6 months.
7. Vornorexant dosage, duration of use, continuation or discontinuation, and clinically recorded adverse events, including somnolence and dizziness, during follow-up.
Six-month assessments will be performed where data are available.

Study type

Observational

Basic design

Randomization

Randomization unit

Blinding

Control

Stratification

Dynamic allocation

Institution consideration

Blocking

Concealment

No. of arms

Purpose of intervention

Type of intervention

Interventions/Control_1

Interventions/Control_2

Interventions/Control_3

Interventions/Control_4

Interventions/Control_5

Interventions/Control_6

Interventions/Control_7

Interventions/Control_8

Interventions/Control_9

Interventions/Control_10

Age-lower limit

18

years-old

<=

Age-upper limit

Not applicable

Gender

Male and Female

Key inclusion criteria

Patients must meet all of the following criteria:
1. Age 18 years or older.
2. Diagnosis of obstructive sleep apnea (OSA) based on polysomnography (PSG) or out-of-center sleep testing (OCST), with initiation of continuous positive airway pressure (CPAP) therapy as part of routine clinical care.
3. No use of hypnotic medications within the preceding month.
4. A baseline Athens Insomnia Scale (AIS) score of 6 or higher before CPAP initiation and a clinical diagnosis of comorbid insomnia by a physician.
5. Provision of written informed consent after receiving an adequate explanation of the study.
COMISA is defined as the coexistence of objectively diagnosed OSA and clinically diagnosed insomnia. An AIS score alone is not sufficient to establish a diagnosis of COMISA.

Key exclusion criteria

Patients meeting any of the following criteria will be excluded:
1. Contraindications to vornorexant according to its package insert, including severe hepatic impairment.
2. Previous prescription of CPAP therapy.
3. Current use of hypnotic medications for insomnia.
4. Sleep disorders other than insomnia and OSA, including central sleep apnea syndrome, central disorders of hypersomnolence such as narcolepsy, or moderate-to-severe restless legs syndrome.
5. Use of medications affecting sleep within the previous 4 weeks.
6. Night-shift or rotating-shift work, markedly irregular sleep schedules, or jet lag.
7. Major causes of poor CPAP adherence other than insomnia, such as severe nasal obstruction or poor mask fit.
8. Pregnancy, breastfeeding, or other conditions for which the attending physician considers study participation inappropriate.
9. Cognitive impairment or other conditions that prevent adequate questionnaire completion or understanding of the study.
10. Inability to obtain objective CPAP usage data.
11. Any other condition considered inappropriate for study participation by the principal investigator or attending physician.
Patients who do not wish to receive vornorexant or who are not prescribed vornorexant as part of routine clinical care will not be excluded for that reason alone and will be followed in the non-prescription group.

Target sample size

60

Name of lead principal investigator

1st name	Yusei
Middle name
Last name	Yamaguchi

Organization

Toho University Omori Medical Center

Division name

Department of Otorhinolaryngology

Zip code

143-8541

Address

6-11-1 Omorinishi, Ota-ku, Tokyo 143-8541, Japan

TEL

03-3762-4151(ext.77937)

Email

yusei.yamaguchi@med.toho-u.ac.jp

Name of contact person

1st name	Yusei
Middle name
Last name	Yamaguchi

Organization

Toho University Omori Medical Center

Division name

Department of Otorhinolaryngology

Zip code

143-8541

Address

6-11-1 Omorinishi, Ota-ku, Tokyo 143-8541, Japan

TEL

03-3762-4151(ext.77937)

Homepage URL

Email

yusei.yamaguchi@med.toho-u.ac.jp

Institute

Toho University

Institute

Department

Personal name

Organization

Toho University

Organization

Division

Category of Funding Organization

Self funding

Nationality of Funding Organization

Japan

Co-sponsor

Name of secondary funder(s)

Organization

Ethics Committee of Toho University School of Medicine

Address

5-21-16 Omorinishi, Ota-ku, Tokyo, Japan

Tel

03-3762-4151(2455)

Email

med.rinri@ext.toho-u.ac.jp

Secondary IDs

NO

Study ID_1

Org. issuing International ID_1

Study ID_2

Org. issuing International ID_2

IND to MHLW

Institutions

東邦大学医療センター大森病院（東京都）

Date of disclosure of the study information

2026

Year

10

Month

28

Day

URL releasing protocol

Publication of results

Unpublished

URL related to results and publications

Number of participants that the trial has enrolled

Results

Results date posted

Results Delayed

Results Delay Reason

Date of the first journal publication of results

Baseline Characteristics

Participant flow

Adverse events

Outcome measures

Plan to share IPD

No plan to share individual participant data (IPD).

IPD sharing Plan description

Individual participant data will be securely managed within the study institution and are not planned to be shared with external researchers or institutions. Any future secondary use will be subject to the required ethics review and institutional procedures.

Recruitment status

Preinitiation

Date of protocol fixation

2026

Year

08

Month

26

Day

Date of IRB

2026

Year

10

Month

26

Day

Anticipated trial start date

2026

Year

10

Month

28

Day

Last follow-up date

2031

Year

01

Month

01

Day

Date of closure to data entry

Date trial data considered complete

Date analysis concluded

Other related information

This is a single-center prospective observational cohort study. Eligible participants are adults aged 18 years or older who are newly initiating CPAP therapy for obstructive sleep apnea (OSA), have a baseline Athens Insomnia Scale (AIS) score of 6 or higher, and are clinically diagnosed with comorbid insomnia (COMISA). Patients meeting the eligibility criteria who provide written informed consent will be enrolled.

No medication will be assigned for research purposes. Vornorexant prescription, dosage, and duration will be determined through shared decision-making between the patient and the treating physician as part of routine clinical care.

Patients prescribed vornorexant will be compared with those not prescribed vornorexant. The primary outcomes are mean nightly CPAP usage during the first 90 days and change in AIS score from baseline to 1 month after CPAP initiation.

Secondary outcomes include the percentage of nights with CPAP use, the percentage of nights with at least 4 hours of CPAP use, CPAP discontinuation, changes in questionnaire scores, and clinically recorded adverse events.

Patients will be followed at 1 and 3 months, and at 6 months where feasible. Potential confounding factors will be considered in the analyses.

The target sample size is 60 patients. Ethics approval number: T2026-173.

Registered date

2026

Year

10

Month

28

Day

Last modified on

2026

Year

10

Month

28

Day

Link to view the page

Value
https://center6.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000072610