Trial · NCT05733286

REPOSE Study: Reducing Delirium by Enhancing Postoperative Sleep With Suvorexant

NCT05733286, Phase 2, Completed, Duke University; results first posted 2026-01-15

3 sourcestrials-2026-11-12-0.5.0

Cite this record

ConductScience Library. REPOSE Study: Reducing Delirium by Enhancing Postoperative Sleep With Suvorexant. Trials, record NCT05733286. Release trials-2026-11-12-0.5.0, 12 Nov 2026. https://conductscience.org/library/trials/NCT05733286

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Trial

As registered on ClinicalTrials.gov, in the graph's capture of the registry.

Title: REPOSE Study: Reducing Delirium by Enhancing Postoperative Sleep With Suvorexant
NCT number: NCT05733286
Status: Completed
Phases: Phase 2
Enrollment: 142 participants, actual
Lead sponsor: Duke University
Conditions: Delirium in Old Age
Interventions: Suvorexant 20 mg, Placebo
First posted: 2023-02-17
Last updated: 2026-01-15
Results first posted: 2026-01-15

Source ClinicalTrials.gov

Registered outcomes7

Each outcome the trial registered, primary first, in ClinicalTrials.gov's words.

List	Outcome	Time frame	Description
Primary	Total Sleep Time (TST) on the First Postoperative Night	The first postoperative night that the participants received study drug (D0)	Total sleep time (TST) on first postoperative night that patient received study drug, as measured by electroencephalography (EEG). Total sleep time includes amount of time in sleep during the lights out period (defined between 21:00 and 06:00).
Secondary	Peak Postoperative Delirium Severity Score	Postoperative Day 0 through Day 5	Three minute Confusion Assessment Method (3D-CAM ) severity scores up through postoperative day 5 or discharge, whichever occurs first, in patients receiving suvorexant vs placebo. Scores range from 0-20 and the higher score is worse.
Other	Postoperative Average Electrographic Total Sleep Time Over the 3-night Recording Period	Postoperative day 0-2	Using the electrographic headband data, differences in postoperative sleep architecture (including stage 2 and 3 NREM sleep and REM sleep) will be compared in participants who received suvorexant compared to those who received placebo using two-sample t-tests. No multiple comparison correction for multiple sleep stages is planned because these are exploratory analyses. Average total sleep time over all nights that participants receive study drug will also be compared using two-sample t-tests.
Other	Average Postoperative Richards-Campbell Subjective Sleep Quality Scores	Postoperative days 1-5	To assess subjective sleep quality, the Richards-Campbell subjective sleep quality questionnaire will be administered daily from postoperative day 1-5 or until hospital discharge, whichever occurs first. The total subjective sleep quality score will be compared between placebo and suvorexant groups using a two-sample t-test.
Other	Change In Pupil Diameter Fluctuations From Preoperative Baseline Through Postoperative Day 3	Preoperative baseline and postoperative days 1-3	Pupillary unrest under ambient light is an index of spontaneous pupil fluctuations that occur secondary to activity of the locus coeruleus, an important brainstem nucleus involved in maintenance of wakefulness and attentional control. Decreased wakefulness has been associated with decreased pupillary unrest at ambient light, suggesting that pupillary unrest at ambient light is a marker of sleep deprivation-related alterations in wakefulness and attention. Here, infrared pupillometry will be used to measure participant's pupil diameter fluctuations under ambient light conditions both before surgery and daily up through postoperative day 3. We will compare postoperative changes in pupillary unrest at ambient light in both suvorexant and placebo-treated using a two-sided t-test.
Other	Changes in Average Response Latency on Preoperative and Postoperative Psychomotor Vigilance Testing	Preoperative baseline, and postoperative days 1-3	Sleep deprivation results in decreased ability to sustain attention, which can be measured with the 5-minute psychomotor vigilance task. The psychomotor vigilance task measures simple reaction times to a visual stimulus over a minute to assess for slowed responses and lapses (i.e., failed response to visual stimuli). Response times, speed, and lapses will be compared between suvorexant and placebo-treated groups to see if postoperative nightly suvorexant has an effect on these sustained attention measures. Using the NASA PVT+ application on an Apple iPad, the psychomotor vigilance task will be collected before surgery, and daily on postoperative day 1-3, or until hospital discharge, whichever occurs first. Analyses will examine pre-to-postoperative change in sustained attention measures to adjust for preoperative performance variability between participants.
Other	Postoperative Hospital Length of Stay	From Postoperative day 0 up to 4 week follow up visit	Postoperative delirium occurs in up to 40% of older surgical patients and has been associated with prolonged hospital stays, long-term cognitive impairment, and increased one-year postoperative mortality. We will record the length of hospital stay for each participant.

Source ClinicalTrials.gov

Outcomes7

Each outcome the trial posted results for, in ClinicalTrials.gov's words.

Type	Outcome	Time frame	Population	Units	Measured as
PRIMARY	Total Sleep Time (TST) on the First Postoperative Night	The first postoperative night that the participants received study drug (D0)	Participants with EEG data for total sleep time determination.	hours	MEAN
SECONDARY	Peak Postoperative Delirium Severity Score	Postoperative Day 0 through Day 5	Participants with 3D-CAM delirium severity scores collected.	score on a scale	MEDIAN
OTHER_PRE_SPECIFIED	Postoperative Average Electrographic Total Sleep Time Over the 3-night Recording Period	Postoperative day 0-2
OTHER_PRE_SPECIFIED	Average Postoperative Richards-Campbell Subjective Sleep Quality Scores	Postoperative days 1-5
OTHER_PRE_SPECIFIED	Change In Pupil Diameter Fluctuations From Preoperative Baseline Through Postoperative Day 3	Preoperative baseline and postoperative days 1-3
OTHER_PRE_SPECIFIED	Changes in Average Response Latency on Preoperative and Postoperative Psychomotor Vigilance Testing	Preoperative baseline, and postoperative days 1-3
OTHER_PRE_SPECIFIED	Postoperative Hospital Length of Stay	From Postoperative day 0 up to 4 week follow up visit

Source ClinicalTrials.gov

Results by group4

Each measurement the trial posted, group by group, in the words and numbers it posted.

Outcome	Group	Value	Spread	Units
Total Sleep Time (TST) on the First Postoperative Night	Suvorexant Arm	3.91	Standard Deviation 2.00	hours
Total Sleep Time (TST) on the First Postoperative Night	Placebo Arm	3.84	Standard Deviation 2.07	hours
Peak Postoperative Delirium Severity Score	Suvorexant Arm	2	Inter-Quartile Range 1 to 3	score on a scale
Peak Postoperative Delirium Severity Score	Placebo Arm	1	Inter-Quartile Range 1 to 3	score on a scale

Source ClinicalTrials.gov

Participant flow6

How many started, completed or left each group, period by period.

Period	Milestone	Group	Participants
Overall Study	STARTED	Suvorexant Arm	68
Overall Study	STARTED	Placebo Arm	60
Overall Study	COMPLETED	Suvorexant Arm	66
Overall Study	COMPLETED	Placebo Arm	57
Overall Study	NOT COMPLETED	Suvorexant Arm	2
Overall Study	NOT COMPLETED	Placebo Arm	3

Source ClinicalTrials.gov

Adverse events66

Each adverse event the trial posted, group by group: the participants affected out of those at risk.

Type	Event	Organ system	Group	Affected	At risk
other	Leg Spasms	Musculoskeletal and connective tissue disorders	Suvorexant Arm	0	66
other	Leg Spasms	Musculoskeletal and connective tissue disorders	Placebo Arm	1	57
other	Self-reported somnolence	Nervous system disorders	Suvorexant Arm	2	66
other	Self-reported somnolence	Nervous system disorders	Placebo Arm	1	57
other	Observed somnolence	Nervous system disorders	Suvorexant Arm	8	66
other	Observed somnolence	Nervous system disorders	Placebo Arm	7	57
other	Abnormal Dreams	Psychiatric disorders	Suvorexant Arm	3	66
other	Abnormal Dreams	Psychiatric disorders	Placebo Arm	5	57
other	Hypnagogic Hallucinations	Psychiatric disorders	Suvorexant Arm	2	66
other	Hypnagogic Hallucinations	Psychiatric disorders	Placebo Arm	0	57

1 to 10 of 66Source ClinicalTrials.gov

See all 66 adverse events

Adverse event totals6

The totals the trial posted for each group.

Total	Group	Affected	At risk
Total, all-cause mortality	Suvorexant Arm	1	66
Total, all-cause mortality	Placebo Arm	0	57
Total, other adverse events	Suvorexant Arm	14	66
Total, other adverse events	Placebo Arm	13	57
Total, serious adverse events	Suvorexant Arm	9	66
Total, serious adverse events	Placebo Arm	9	57

Source ClinicalTrials.gov

Papers1

The papers the trial lists on ClinicalTrials.gov.

PMID	Listed as
40081971	DERIVED

Source PubMed

Grants0

The grants NIH RePORTER links to the trial, newest funded first: NIH's, and some of AHRQ's, CDC's, FDA's and VA's. Each shows its title, principal investigators, organization and funder in its newest year.

None in this release.

Trial comparisons2

Comparisons of the trial's two groups, calculated by ConductScience from the counts it posted.

Comparison	Source
Suvorexant Arm vs Placebo Arm: deaths from any cause	Trial comparisons
Suvorexant Arm vs Placebo Arm: serious adverse events	Trial comparisons

Tests2

The ConductCognition tests this trial's registered outcomes name, as ScienceGraph matched them in trial-tests-2026-11-12-0.2.1.

Test	Named as	Source
Psychomotor Vigilance Task	Other outcome	ConductCognition
Simple Reaction Time	Other outcome	ConductCognition

Data dates

The day each source was copied for this release.

ClinicalTrials.gov: 2026-11-12; ClinicalTrials.gov
Results, from AACT: 2026-03-23; AACT
NIH grant links: 2026-11-13; NIH RePORTER

Sources 3

ClinicalTrials.gov's posted results, through CTTI's AACTFreely available. Acknowledgement requested
ClinicalTrials.govNo license stated
NIH RePORTER's clinical studies and project filesPublic domain

Each source's terms

ClinicalTrials.gov's posted results, through CTTI's AACTClinicalTrials.gov data via Aggregate Analysis of ClinicalTrials.gov (AACT), CTTI. CTTI makes its materials freely available and requests acknowledgement. https://aact.ctti-clinicaltrials.org/documentation/299
ClinicalTrials.govnone stated
NIH RePORTER's clinical studies and project filesPublic domain (NIH RePORTER)

ClinicalTrials.gov's data carry an international copyright outside the United States: https://clinicaltrials.gov/about-site/terms-conditions.

For software

Read this trial from software.

The record and each of its lists are JSON, twenty rows a page. No key.

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