Trial Outcomes & Findings for Suvorexant to Reduce Symptoms of Nicotine Use (NCT NCT04234997)

NCT ID: NCT04234997

Last Updated: 2025-10-01

Results Overview

Duration as the total amount of time asleep. Change in sleep duration is reported as \[(Day 8 Sleep Duration ) - (Day 1 Sleep Duration)\]

• Recruitment status: COMPLETED
• Study phase: PHASE2
• Target enrollment: 14 participants
• Primary outcome timeframe: Day 1, Day 8
• Results posted on: 2025-10-01

Participant Flow

Of the 14 enrolled participants, 11 were randomized and 3 withdrew from the study before randomization.

Participant milestones

Measure	Suvorexant 20 mg Suvorexant 20 mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.	Suvorexant 0mg Suvorexant 0mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.
Overall Study STARTED	5	6
Overall Study COMPLETED	3	5
Overall Study NOT COMPLETED	2	1

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

Suvorexant to Reduce Symptoms of Nicotine Use

Baseline characteristics by cohort

Measure	Suvorexant 20 mg n=5 Participants Suvorexant 20 mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.	Suvorexant 0mg n=6 Participants Suvorexant 0mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.	Total n=11 Participants Total of all reporting groups
Age, Continuous	52.60 years STANDARD_DEVIATION 7.92 • n=5 Participants	46.67 years STANDARD_DEVIATION 7.15 • n=7 Participants	49.36 years STANDARD_DEVIATION 7.76 • n=5 Participants
Sex: Female, Male Female	1 Participants n=5 Participants	2 Participants n=7 Participants	3 Participants n=5 Participants
Sex: Female, Male Male	4 Participants n=5 Participants	4 Participants n=7 Participants	8 Participants n=5 Participants
Ethnicity (NIH/OMB) Hispanic or Latino	1 Participants n=5 Participants	2 Participants n=7 Participants	3 Participants n=5 Participants
Ethnicity (NIH/OMB) Not Hispanic or Latino	4 Participants n=5 Participants	4 Participants n=7 Participants	8 Participants n=5 Participants
Ethnicity (NIH/OMB) Unknown or Not Reported	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants
Race/Ethnicity, Customized African-American	3 Participants n=5 Participants	4 Participants n=7 Participants	7 Participants n=5 Participants
Race/Ethnicity, Customized White	2 Participants n=5 Participants	1 Participants n=7 Participants	3 Participants n=5 Participants
Race/Ethnicity, Customized Not Reported	0 Participants n=5 Participants	1 Participants n=7 Participants	1 Participants n=5 Participants
Region of Enrollment United States	5 participants n=5 Participants	6 participants n=7 Participants	11 participants n=5 Participants
Years of Education	12.20 years STANDARD_DEVIATION 0.45 • n=5 Participants	12.83 years STANDARD_DEVIATION 1.83 • n=7 Participants	12.55 years STANDARD_DEVIATION 1.37 • n=5 Participants
Nicotine dependence as assessed by the Fagerstrom Test for Nicotine Dependence	5.80 score on a scale STANDARD_DEVIATION 1.64 • n=5 Participants	6.17 score on a scale STANDARD_DEVIATION 1.94 • n=7 Participants	6.00 score on a scale STANDARD_DEVIATION 1.73 • n=5 Participants
Cognitive ability as assessed by Shipley 2- Composite B	91.00 score on a scale STANDARD_DEVIATION 14.07 • n=5 Participants	98.00 score on a scale STANDARD_DEVIATION 10.83 • n=7 Participants	94.82 score on a scale STANDARD_DEVIATION 12.29 • n=5 Participants

PRIMARY outcome

Timeframe: Day 1

The VAS total score ranges from 1(none) to 10(extreme stress);a higher score indicating a worse outcome.

Outcome measures

Measure	Suvorexant 20 mg n=5 Participants Suvorexant 20 mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.	Suvorexant 0mg n=6 Participants Suvorexant 0mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.
Stress as Assessed by a Visual Analog Scale (VAS) for Stress	3.4 score on a scale Standard Deviation 2.07	3 score on a scale Standard Deviation 2.61

PRIMARY outcome

Timeframe: Day 8

The VAS total score ranges from 1(none) to 10(extreme stress);a higher score indicating a worse outcome.

Outcome measures

Measure	Suvorexant 20 mg n=3 Participants Suvorexant 20 mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.	Suvorexant 0mg n=5 Participants Suvorexant 0mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.
Stress as Assessed by a Visual Analog Scale (VAS) for Stress	3.33 score on a scale Standard Deviation 2.89	3.2 score on a scale Standard Deviation 2.39

PRIMARY outcome

Timeframe: Day 1 baseline (about 15 minutes before cold pressor task) and about 2 minutes after the start of the cold pressor task

During the cold pressor task (CPT), participants will submerge their dominant arm in an ice-water bath for up to 2 minutes. Heart rate will be collected pre CPT (about 15 minutes before cold pressor task) and post CPT (about 2 minutes after the start of the cold pressor task). The change in Heart rate will be reported as [(Heart rate post cold pressor task) - (Heart rate pre cold pressor task)].

Outcome measures

Measure	Suvorexant 20 mg n=5 Participants Suvorexant 20 mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.	Suvorexant 0mg n=6 Participants Suvorexant 0mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.
Change in Stress Reactivity as Assessed by Heart Rate During the Cold Pressor Test (CPT)	5 beats per minutes (bpm) Standard Deviation 1.581	9.5 beats per minutes (bpm) Standard Deviation 3.728

PRIMARY outcome

Timeframe: Day 8 baseline (about 15 minutes before cold pressor task) and about 2 minutes after the start of the cold pressor task

During the cold pressor task (CPT), participants will submerge their dominant arm in an ice-water bath for up to 2 minutes. Heart rate will be collected pre CPT (about 15 minutes before cold pressor task) and post CPT (about 2 minutes after the start of the cold pressor task). The change in Heart rate will be reported as [(Heart rate post cold pressor task) - (Heart rate pre cold pressor task)].

Outcome measures

Measure	Suvorexant 20 mg n=3 Participants Suvorexant 20 mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.	Suvorexant 0mg n=5 Participants Suvorexant 0mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.
Change in Stress Reactivity as Assessed by Heart Rate During the Cold Pressor Test (CPT)	3.667 beats per minutes (bpm) Standard Deviation 1.528	9 beats per minutes (bpm) Standard Deviation 4.183

PRIMARY outcome

Timeframe: Day 1 baseline (about 15 minutes before cold pressor task) and about 30 minutes after the start of the cold pressor task, Day 8 baseline (about 15 minutes before cold pressor task) and about 30 minutes after the start of the cold pressor task

Population: All cortisol samples were compromised during collection and storage due to cross-contamination between control and experimental samples. As a result, the samples could not be processed, and no outcome data were collected.

During the cold pressor task (CPT), participants will submerge their dominant arm in an ice-water bath for up to 2 minutes. Saliva samples will be collected pre CPT (about 15 minutes before cold pressor task) and post CPT (about 30 minutes after the start of the cold pressor task), and cortisol levels in the saliva samples will be assessed. The change in cortisol level will be reported as [(cortisol level at post cold pressor task) - (cortisol level pre cold pressor task)].

Outcome measures

Outcome data not reported

PRIMARY outcome

Timeframe: Day 1

Latency to self-administration is defined as the time (in minutes) from the beginning of the relapse assessment session until the participant initiates smoking their first cigarette.

Outcome measures

Measure	Suvorexant 20 mg n=5 Participants Suvorexant 20 mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.	Suvorexant 0mg n=6 Participants Suvorexant 0mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.
Smoking as Assessed by Latency to Self-Administration During the Smoking Relapse Assessment	56.8 minutes Standard Deviation 4.44	22.67 minutes Standard Deviation 22.99

PRIMARY outcome

Timeframe: Day 1

The outcome measure is the number of cigarettes self-administered by each participant during the Smoking Relapse Assessment.

Outcome measures

Measure	Suvorexant 20 mg n=5 Participants Suvorexant 20 mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.	Suvorexant 0mg n=6 Participants Suvorexant 0mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.
Smoking as Assessed by Number of Self-Administrated Cigarettes During the Smoking Relapse Assessment	0.8 cigarettes Standard Deviation 1.3	1.33 cigarettes Standard Deviation 0.52

PRIMARY outcome

Timeframe: Day 1, Day 8

Population: Data were not collected from 3 participants in the Suvorexant 20 mg arm and Data were not collected for 5 participants in the Suvorexant 0mg due to device malfunction and/or user error.

Quality defined as proportion of time in deep sleep. Change in sleep quality is reported as [(Day 8 Sleep Quality ) - (Day 1 Sleep quality)]

Outcome measures

Measure	Suvorexant 20 mg n=2 Participants Suvorexant 20 mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.	Suvorexant 0mg n=1 Participants Suvorexant 0mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.
Change in Sleep Quality as Assessed by the Garmin Vivosmart3 Actigraphy Device	-0.038 minutes Standard Deviation 0.1	0.4 minutes

PRIMARY outcome

Timeframe: Day 1, Day 8

Population: Data were not collected from 3 participants in the Suvorexant 20 mg arm and Data were not collected for 5 participants in the Suvorexant 0mg due to device malfunction and/or user error.

Duration as the total amount of time asleep. Change in sleep duration is reported as [(Day 8 Sleep Duration ) - (Day 1 Sleep Duration)]

Outcome measures

Measure	Suvorexant 20 mg n=2 Participants Suvorexant 20 mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.	Suvorexant 0mg n=1 Participants Suvorexant 0mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.
Change in Sleep Duration as Assessed by the Garmin Vivosmart3 Actigraphy Device	-195.5 minutes Standard Deviation 229.8	79 minutes

PRIMARY outcome

Timeframe: Day 1, Day 8

Population: Data were not collected from 3 participants in the Suvorexant 20 mg arm and Data were not collected for 5 participants in the Suvorexant 0mg due to device malfunction and/or user error.

Restlessness as the number of times waking up during sleep. Change in sleep restlessness is reported as [(Day 8 Sleep restlessness) - (Day 1 Sleep restlessness]

Outcome measures

Measure	Suvorexant 20 mg n=2 Participants Suvorexant 20 mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.	Suvorexant 0mg n=1 Participants Suvorexant 0mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.
Change in Sleep Restlessness as Assessed by the Garmin Vivosmart3 Actigraphy Device	0.5 number of times awake Standard Deviation 0.707	7 number of times awake

PRIMARY outcome

Timeframe: Day 8

The outcome measure is the number of cigarettes self-administered by each participant during the Smoking Relapse Assessment.

Outcome measures

Measure	Suvorexant 20 mg n=3 Participants Suvorexant 20 mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.	Suvorexant 0mg n=5 Participants Suvorexant 0mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.
Smoking as Assessed by Number of Self-Administrated Cigarettes During the Smoking Relapse Assessment	1.33 cigarettes Standard Deviation 2.31	1.4 cigarettes Standard Deviation 0.55

PRIMARY outcome

Timeframe: Day 8

Latency to self-administration is defined as the time (in minutes) from the beginning of the relapse assessment session until the participant initiates smoking their first cigarette.

Outcome measures

Measure	Suvorexant 20 mg n=3 Participants Suvorexant 20 mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.	Suvorexant 0mg n=5 Participants Suvorexant 0mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.
Smoking as Assessed by Latency to Self-Administration During the Smoking Relapse Assessment	56.67 minutes Standard Deviation 5.77	16.2 minutes Standard Deviation 22.02

PRIMARY outcome

Timeframe: Day 1

The Questionnaire of Smoking Urgers (QSU-brief) total score ranges from 10 to 70, higher score indicates greater nicotine craving.

Outcome measures

Measure	Suvorexant 20 mg n=5 Participants Suvorexant 20 mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.	Suvorexant 0mg n=6 Participants Suvorexant 0mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.
Nicotine Craving as Assessed by the Questionnaire of Smoking Urgers (QSU-brief)	45.8 score on a scale Standard Deviation 12.24	36.67 score on a scale Standard Deviation 14.92

PRIMARY outcome

Timeframe: Day 8

The Questionnaire of Smoking Urgers (QSU-brief) total score ranges from 10 to 70, higher score indicates greater nicotine craving.

Outcome measures

Measure	Suvorexant 20 mg n=3 Participants Suvorexant 20 mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.	Suvorexant 0mg n=5 Participants Suvorexant 0mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.
Nicotine Craving as Assessed by the Questionnaire of Smoking Urgers (QSU-brief)	47.67 score on a scale Standard Deviation 17.21	39.8 score on a scale Standard Deviation 11.17

SECONDARY outcome

Timeframe: Day 1

The Stress Subscale of the Depression, Anxiety and Stress scale (DASS-21) assesses stress levels. Total score on the DASS-21 stress subscale ranges from 0 to 21, with a higher score indicating higher stress.

Outcome measures

Measure	Suvorexant 20 mg n=5 Participants Suvorexant 20 mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.	Suvorexant 0mg n=6 Participants Suvorexant 0mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.
Stress as Assessed by the Depression-Anxiety-Stress 21 (DASS21) Self-Report Questionnaire - Stress Subscale	0.8 score on a scale Standard Deviation 0.84	3.5 score on a scale Standard Deviation 2.74

SECONDARY outcome

Timeframe: Day 8

The Stress Subscale of the Depression, Anxiety and Stress scale (DASS-21) assesses stress levels. Total score on the DASS-21 stress subscale ranges from 0 to 21, with a higher score indicating higher stress.

Outcome measures

Measure	Suvorexant 20 mg n=3 Participants Suvorexant 20 mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.	Suvorexant 0mg n=5 Participants Suvorexant 0mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.
Stress as Assessed by the Depression-Anxiety-Stress 21 (DASS21) Self-Report Questionnaire - Stress Subscale	1.33 score on a scale Standard Deviation 1.15	5.2 score on a scale Standard Deviation 4.15

SECONDARY outcome

Timeframe: Day 1

The Personal Stress Scale (PSS) total score ranges from 0 to 40, a higher score indicating greater stress.

Outcome measures

Measure	Suvorexant 20 mg n=5 Participants Suvorexant 20 mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.	Suvorexant 0mg n=6 Participants Suvorexant 0mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.
Stress as Assessed by the Personal Stress Scale (PSS)	17.2 score on a scale Standard Deviation 4.15	19 score on a scale Standard Deviation 2.61

SECONDARY outcome

Timeframe: Day 8

The Personal Stress Scale (PSS) total score ranges from 0 to 40, a higher score indicating greater stress.

Outcome measures

Measure	Suvorexant 20 mg n=3 Participants Suvorexant 20 mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.	Suvorexant 0mg n=5 Participants Suvorexant 0mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.
Stress as Assessed by the Personal Stress Scale (PSS)	18 score on a scale Standard Deviation 6.24	17.4 score on a scale Standard Deviation 2.88

SECONDARY outcome

Timeframe: Day 1 baseline (about 15 minutes before cold pressor task) and about 2 minutes after the start of the cold pressor task

During the cold pressor task (CPT), participants will submerge their dominant arm in an ice-water bath for up to 2 minutes. Systolic Blood Pressure will be collected pre CPT (about 15 minutes before cold pressor task) and post CPT (about 2 minutes after the start of the cold pressor task). The change in Systolic Blood Pressure will be reported as [( Systolic Blood Pressure at post cold pressor task) - (Systolic Blood Pressure at pre cold pressor task)].

Outcome measures

Measure	Suvorexant 20 mg n=5 Participants Suvorexant 20 mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.	Suvorexant 0mg n=6 Participants Suvorexant 0mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.
Change in Stress Reactivity as Assessed by Systolic Blood Pressure During the Cold Pressor Test (CPT)	17.6 millimeters of mercury (mmHg) Standard Deviation 18.94	27.833 millimeters of mercury (mmHg) Standard Deviation 10.572

SECONDARY outcome

Timeframe: Day 8 baseline (about 15 minutes before cold pressor task) and about 2 minutes after the start of the cold pressor task

During the cold pressor task (CPT), participants will submerge their dominant arm in an ice-water bath for up to 2 minutes. Systolic Blood Pressure will be collected pre CPT (about 15 minutes before cold pressor task) and post CPT (about 2 minutes after the start of the cold pressor task) The change in Systolic Blood Pressure will be reported as [( Systolic Blood Pressure at post cold pressor task) - (Systolic Blood Pressure at pre cold pressor task)].

Outcome measures

Measure	Suvorexant 20 mg n=3 Participants Suvorexant 20 mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.	Suvorexant 0mg n=5 Participants Suvorexant 0mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.
Change in Stress Reactivity as Assessed by Systolic Blood Pressure During the Cold Pressor Test (CPT)	18 millimeters of mercury (mmHg) Standard Deviation 11.358	16 millimeters of mercury (mmHg) Standard Deviation 8.276

SECONDARY outcome

Timeframe: Day 1 baseline (about 15 minutes before cold pressor task) and about 2 minutes after the start of the cold pressor task

During the cold pressor task (CPT), participants will submerge their dominant arm in an ice-water bath for up to 2 minutes. Diastolic Blood Pressure will be collected pre CPT (about 15 minutes before cold pressor task) and post CPT (about 2 minutes after the start of the cold pressor task). The change in Diastolic Blood Pressure will be reported as [( Diastolic Blood Pressure at post cold pressor task) - (Diastolic Blood Pressure at pre cold pressor task)].

Outcome measures

Measure	Suvorexant 20 mg n=5 Participants Suvorexant 20 mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.	Suvorexant 0mg n=6 Participants Suvorexant 0mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.
Change in Stress Reactivity as Assessed by Diastolic Blood Pressure During the Cold Pressor Test (CPT)	7.4 millimeters of mercury (mmHg) Standard Deviation 9.449	22.667 millimeters of mercury (mmHg) Standard Deviation 8.165

SECONDARY outcome

Timeframe: Day 8 baseline (about 15 minutes before cold pressor task) and about 2 minutes after the start of the cold pressor task

During the cold pressor task (CPT), participants will submerge their dominant arm in an ice-water bath for up to 2 minutes. Diastolic Blood Pressure will be collected pre CPT (about 15 minutes before cold pressor task) and post CPT (about 2 minutes after the start of the cold pressor task).The change in Diastolic Blood Pressure will be reported as [( Diastolic Blood Pressure at post cold pressor task) - (Diastolic Blood Pressure at pre cold pressor task)].

Outcome measures

Measure	Suvorexant 20 mg n=3 Participants Suvorexant 20 mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.	Suvorexant 0mg n=5 Participants Suvorexant 0mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.
Change in Stress Reactivity as Assessed by Diastolic Blood Pressure During the Cold Pressor Test (CPT)	9.667 millimeters of mercury (mmHg) Standard Deviation 3.512	14.8 millimeters of mercury (mmHg) Standard Deviation 4.382

SECONDARY outcome

Timeframe: Day 1

Patient-Reported Outcomes Measurement Information System(PROMIS) Sleep Disturbance Short Form total score ranges from 8 to 40, a higher score indicating worse sleep quality.

Outcome measures

Measure	Suvorexant 20 mg n=5 Participants Suvorexant 20 mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.	Suvorexant 0mg n=6 Participants Suvorexant 0mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.
Sleep Quality as Assessed by the Patient-Reported Outcomes Measurement Information System(PROMIS) Sleep Disturbance Short Form	16.4 score on a scale Standard Deviation 6.07	18.83 score on a scale Standard Deviation 8.89

SECONDARY outcome

Timeframe: Day 8

Patient-Reported Outcomes Measurement Information System(PROMIS) Sleep Disturbance Short Form total score ranges from 8 to 40, a higher score indicating worse sleep quality.

Outcome measures

Measure	Suvorexant 20 mg n=3 Participants Suvorexant 20 mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.	Suvorexant 0mg n=5 Participants Suvorexant 0mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.
Sleep Quality as Assessed by the Patient-Reported Outcomes Measurement Information System(PROMIS) Sleep Disturbance Short Form	16 score on a scale Standard Deviation 5.2	21.4 score on a scale Standard Deviation 10.76

SECONDARY outcome

Timeframe: Day 1

The Epworth Sleepiness Scale (ESS) total score ranges from 0 to 24, a higher score indicating worse sleep quality.

Outcome measures

Measure	Suvorexant 20 mg n=5 Participants Suvorexant 20 mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.	Suvorexant 0mg n=6 Participants Suvorexant 0mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.
Sleep Quality as Assessed by the Epworth Sleepiness Scale (ESS)	9.8 score on a scale Standard Deviation 6.61	7.67 score on a scale Standard Deviation 5.35

SECONDARY outcome

Timeframe: Day 8

The Epworth Sleepiness Scale (ESS) total score ranges from 0 to 24, a higher score indicating worse sleep quality.

Outcome measures

Measure	Suvorexant 20 mg n=3 Participants Suvorexant 20 mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.	Suvorexant 0mg n=5 Participants Suvorexant 0mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.
Sleep Quality as Assessed by the Epworth Sleepiness Scale (ESS)	12.67 score on a scale Standard Deviation 8.62	11 score on a scale Standard Deviation 6.04

SECONDARY outcome

Timeframe: Day 1

The Minnesota Nicotine Withdrawal Questionnaire (MNWQ) total score ranges from 0 to 36 with higher scores indicating greater withdrawal symptoms.

Outcome measures

Measure	Suvorexant 20 mg n=5 Participants Suvorexant 20 mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.	Suvorexant 0mg n=6 Participants Suvorexant 0mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.
Withdrawal Severity as Assessed by the Minnesota Nicotine Withdrawal Questionnaire (MNWQ)	9.6 score on a scale Standard Deviation 7.8	6.67 score on a scale Standard Deviation 3.93

SECONDARY outcome

Timeframe: Day 8

The Minnesota Nicotine Withdrawal Questionnaire (MNWQ) total score ranges from 0 to 36 with higher scores indicating greater withdrawal symptoms.

Outcome measures

Measure	Suvorexant 20 mg n=3 Participants Suvorexant 20 mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.	Suvorexant 0mg n=5 Participants Suvorexant 0mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.
Withdrawal Severity as Assessed by the Minnesota Nicotine Withdrawal Questionnaire (MNWQ)	7 score on a scale Standard Deviation 5.29	11.6 score on a scale Standard Deviation 7.02

SECONDARY outcome

Timeframe: Day 1

The Hamilton Anxiety Rating Scale (HAM-A) total score ranges from 0 to 56, a higher score indicating greater anxiety.

Outcome measures

Measure	Suvorexant 20 mg n=5 Participants Suvorexant 20 mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.	Suvorexant 0mg n=6 Participants Suvorexant 0mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.
Anxiety a Measured by the Hamilton Anxiety Rating Scale (HAM-A)	2.8 score on a scale Standard Deviation 2.05	3.17 score on a scale Standard Deviation 1.47

SECONDARY outcome

Timeframe: Day 8

The Hamilton Anxiety Rating Scale (HAM-A) total score ranges from 0 to 56, a higher score indicating greater anxiety.

Outcome measures

Measure	Suvorexant 20 mg n=3 Participants Suvorexant 20 mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.	Suvorexant 0mg n=5 Participants Suvorexant 0mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.
Anxiety a Measured by the Hamilton Anxiety Rating Scale (HAM-A)	2.33 score on a scale Standard Deviation 3.21	3 score on a scale Standard Deviation 1.22

SECONDARY outcome

Timeframe: Day 1

The Pittsburgh Sleep Quality Index (PSQI) total score ranges from 0 to 21, a higher score indicates worse sleep quality.

Outcome measures

Measure	Suvorexant 20 mg n=5 Participants Suvorexant 20 mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.	Suvorexant 0mg n=6 Participants Suvorexant 0mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.
Sleep Quality as Assessed by the Pittsburgh Sleep Quality Index (PSQI)	8 score on a scale Standard Error 2.55	8.67 score on a scale Standard Error 5.54

SECONDARY outcome

Timeframe: Day 8

The Pittsburgh Sleep Quality Index (PSQI) total score ranges from 0 to 21, a higher score indicates worse sleep quality.

Outcome measures

Measure	Suvorexant 20 mg n=3 Participants Suvorexant 20 mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.	Suvorexant 0mg n=5 Participants Suvorexant 0mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.
Sleep Quality as Assessed by the Pittsburgh Sleep Quality Index (PSQI)	7 score on a scale Standard Error 2	9.8 score on a scale Standard Error 4.44

SECONDARY outcome

Timeframe: Day 1

The Anxiety Subscale of the Depression, Anxiety and Stress scale (DASS-21) assesses anxiety levels. Total score on the DASS-21 stress subscale ranges from 0 to 21, with a higher score indicating greater anxiety.

Outcome measures

Measure	Suvorexant 20 mg n=5 Participants Suvorexant 20 mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.	Suvorexant 0mg n=6 Participants Suvorexant 0mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.
Anxiety as Assessed by the Depression-Anxiety-Stress 21 (DASS21) Self-Report Questionnaire - Anxiety Subscale	0.8 score on a scale Standard Deviation 1.3	2.5 score on a scale Standard Deviation 2.17

SECONDARY outcome

Timeframe: Day 8

The Anxiety Subscale of the Depression, Anxiety and Stress scale (DASS-21) assesses anxiety levels. Total score on the DASS-21 stress subscale ranges from 0 to 21, with a higher score indicating greater anxiety.

Outcome measures

Measure	Suvorexant 20 mg n=3 Participants Suvorexant 20 mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.	Suvorexant 0mg n=5 Participants Suvorexant 0mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.
Anxiety as Assessed by the Depression-Anxiety-Stress 21 (DASS21) Self-Report Questionnaire - Anxiety Subscale	0.67 score on a scale Standard Deviation 0.58	3 score on a scale Standard Deviation 3

SECONDARY outcome

Timeframe: Day 1 baseline (about 15 minutes before cold pressor task) and about 30 minutes after the start of the cold pressor task

During the cold pressor task (CPT), participants will submerge their dominant arm in an ice-water bath for up to 2 minutes. The VAS total score ranges from 1(none) to 10(extreme stress);a higher score indicating a worse outcome. Visual Analog Scale (VAS) for stress score will be collected before and after the CPT. The change in Stress will be reported as [( Visual Analog Scale (VAS) for stress score at post cold pressor task) - (Visual Analog Scale (VAS) for stress score at pre cold pressor task)].

Outcome measures

Measure	Suvorexant 20 mg n=5 Participants Suvorexant 20 mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.	Suvorexant 0mg n=6 Participants Suvorexant 0mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.
Change in Stress as Assessed by Visual Analog Scale (VAS) for Stress During the Cold Pressor Test (CPT)	0 score on a scale Standard Deviation 0.707	0 score on a scale Standard Deviation 0

SECONDARY outcome

Timeframe: Day 8 baseline (about 15 minutes before cold pressor task) and about 30 minutes after the start of the cold pressor task

During the cold pressor task (CPT), participants will submerge their dominant arm in an ice-water bath for up to 2 minutes. The VAS total score ranges from 1(none) to 10(extreme stress);a higher score indicating a worse outcome. Visual Analog Scale (VAS) for stress score will be collected before and after the CPT. The change in Stress will be reported as [( Visual Analog Scale (VAS) for stress score at post cold pressor task) - (Visual Analog Scale (VAS) for stress score at pre cold pressor task)].

Outcome measures

Measure	Suvorexant 20 mg n=3 Participants Suvorexant 20 mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.	Suvorexant 0mg n=5 Participants Suvorexant 0mg: Participants will be advised to take the medication at 10PM for 7 days.Participants will be instructed to stop smoking by 10 pm the day before, in order to ensure they meet the breath CO criterion (CO ≤ 4 ppm) indicating overnight abstinence.
Change in Stress as Assessed by Visual Analog Scale (VAS) for Stress During the Cold Pressor Test (CPT)	1 score on a scale Standard Deviation 1	-0.2 score on a scale Standard Deviation 0.447

Adverse Events

Suvorexant 20 mg

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

Suvorexant 0mg

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Adverse event data not reported

Additional Information

Robert Suchting, MD

The University of Texas Health Science Center at Houston

Phone: 713-486-2521

Email: Robert.Suchting@uth.tmc.edu

Results disclosure agreements

• Principal investigator is a sponsor employee
• Publication restrictions are in place