Trial Outcomes & Findings for Psilocybin-facilitated Smoking Cessation Treatment: A Pilot Study (NCT NCT01943994)

NCT ID: NCT01943994

Last Updated: 2025-05-25

Results Overview

Cigarette smoking abstinence from the target quit (allowing for an initial 14-day grace period) to the 6-month follow up, as verified by breath carbon monoxide, urine cotinine, and retrospective self-report.

Recruitment status

COMPLETED

Study phase

Target enrollment

82 participants

Primary outcome timeframe

From the target quit date to the 6-month follow up

Results posted on

2025-05-25

Participant Flow

Participant milestones

Participant milestones
Measure	Psilocybin-assisted Treatment Participants will receive a 13-week cognitive behavioral intervention for smoking cessation, with a high dose of psilocybin (30mg / 70kg) to be administered on the Target Quit Date in week 5. Psilocybin-assisted treatment: Participants will be administered 30 mg/70 kg psilocybin. Preliminary evidence from our ongoing psilocybin dose-effects study suggests that this dose is associated with mystical-type experiences.	Nicotine Replacement Therapy (NRT) First, Then Psilocybin-assisted Treatment Participants will receive a 13-week cognitive behavioral intervention for smoking cessation, with a standard 8 to 10-week regimen of NRT to be administered beginning on the Target Quit Date in week 5. NRT for this study will be a transdermal nicotine patch administered according to recommended label usage (For individuals who smoke more than 10 cigarettes per day: 21mg daily weeks 1-6, 14mg daily weeks 7-8, 7mg daily weeks 9-10. For individuals who smoke 10 or less cigarettes per day: 14mg daily for weeks 1-6, 7mg daily for weeks 7-8). Participants who were initially assigned to the "Nicotine Replacement Therapy (NRT)" Arm/Group had the option to cross-over to "Psilocybin-assisted Treatment" at 6 months.
Period 1: Initial Treatment (6 Months) STARTED	42	40
Period 1: Initial Treatment (6 Months) COMPLETED	35	34
Period 1: Initial Treatment (6 Months) NOT COMPLETED	7	6
Period 2: Optional Cross-over (6 Months) STARTED	35	34
Period 2: Optional Cross-over (6 Months) Participants Who Completed the Optional Cross-over Psilocybin Session	0	26
Period 2: Optional Cross-over (6 Months) COMPLETED	34	28
Period 2: Optional Cross-over (6 Months) NOT COMPLETED	1	6

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

Psilocybin-facilitated Smoking Cessation Treatment: A Pilot Study

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	Psilocybin-assisted Treatment n=42 Participants Participants will receive a 13-week cognitive behavioral intervention for smoking cessation, with a high dose of psilocybin (30mg / 70kg) to be administered on the Target Quit Date in week 5. Psilocybin-assisted treatment: Participants will be administered 30 mg/70 kg psilocybin. Preliminary evidence from our ongoing psilocybin dose-effects study suggests that this dose is associated with mystical-type experiences.	Nicotine Replacement Therapy (NRT) First, Then Psilocybin-assisted Treatment n=40 Participants Participants will receive a 13-week cognitive behavioral intervention for smoking cessation, with a standard 8 to 10-week regimen of NRT to be administered beginning on the Target Quit Date in week 5. NRT for this study will be a transdermal nicotine patch administered according to recommended label usage (For individuals who smoke more than 10 cigarettes per day: 21mg daily weeks 1-6, 14mg daily weeks 7-8, 7mg daily weeks 9-10. For individuals who smoke 10 or less cigarettes per day: 14mg daily for weeks 1-6, 7mg daily for weeks 7-8). Participants who were initially assigned to the "Nicotine Replacement Therapy (NRT)" Arm/Group had the option to cross-over to "Psilocybin-assisted Treatment" at 6 months.	Total n=82 Participants Total of all reporting groups
Age, Categorical <=18 years	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants
Age, Categorical Between 18 and 65 years	38 Participants n=5 Participants	40 Participants n=7 Participants	78 Participants n=5 Participants
Age, Categorical >=65 years	4 Participants n=5 Participants	0 Participants n=7 Participants	4 Participants n=5 Participants
Age, Continuous	48.48 years STANDARD_DEVIATION 11.93 • n=5 Participants	46.75 years STANDARD_DEVIATION 12.26 • n=7 Participants	47.63 years STANDARD_DEVIATION 12.05 • n=5 Participants
Sex: Female, Male Female	19 Participants n=5 Participants	14 Participants n=7 Participants	33 Participants n=5 Participants
Sex: Female, Male Male	23 Participants n=5 Participants	26 Participants n=7 Participants	49 Participants n=5 Participants
Race (NIH/OMB) American Indian or Alaska Native	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants
Race (NIH/OMB) Asian	1 Participants n=5 Participants	3 Participants n=7 Participants	4 Participants n=5 Participants
Race (NIH/OMB) Native Hawaiian or Other Pacific Islander	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants
Race (NIH/OMB) Black or African American	3 Participants n=5 Participants	0 Participants n=7 Participants	3 Participants n=5 Participants
Race (NIH/OMB) White	38 Participants n=5 Participants	35 Participants n=7 Participants	73 Participants n=5 Participants
Race (NIH/OMB) More than one race	0 Participants n=5 Participants	2 Participants n=7 Participants	2 Participants n=5 Participants
Race (NIH/OMB) Unknown or Not Reported	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants
Region of Enrollment United States	42 Participants n=5 Participants	40 Participants n=7 Participants	82 Participants n=5 Participants

PRIMARY outcome

Timeframe: From the target quit date to the 6-month follow up

Outcome measures

Outcome measures
Measure	Nicotine Replacement Therapy (NRT) First, Then Psilocybin-assisted Treatment n=40 Participants Participants will receive a 13-week cognitive behavioral intervention for smoking cessation, with a standard 8 to 10-week regimen of NRT to be administered beginning on the Target Quit Date in week 5. NRT for this study will be a transdermal nicotine patch administered according to recommended label usage (For individuals who smoke more than 10 cigarettes per day: 21mg daily weeks 1-6, 14mg daily weeks 7-8, 7mg daily weeks 9-10. For individuals who smoke 10 or less cigarettes per day: 14mg daily for weeks 1-6, 7mg daily for weeks 7-8). Participants who were initially assigned to the "Nicotine Replacement Therapy (NRT)" Arm/Group had the option to cross-over to "Psilocybin-assisted Treatment" at 6 months.	Psilocybin-assisted Treatment n=42 Participants Participants will receive a 13-week cognitive behavioral intervention for smoking cessation, with a high dose of psilocybin (30mg / 70kg) to be administered on the Target Quit Date in week 5. Psilocybin-assisted treatment: Participants will be administered 30 mg/70 kg psilocybin. Preliminary evidence from our ongoing psilocybin dose-effects study suggests that this dose is associated with mystical-type experiences.	Cross-over to Psilocybin-assisted Treatment Participants in the Nicotine Replacement Therapy (NRT) arm were also eligible to receive a single high-dose (30mg/70kg) psilocybin administration after completing the primary study endpoint at 6-month follow-up. Thus, individuals in this category opted to complete this cross-over psilocybin session after completing a course of NRT.
Prolonged Abstinence: Biologically Verified Cigarette Smoking Abstinence for 6 Months	4 Participants	17 Participants	—

SECONDARY outcome

Timeframe: From the target quit date to the 3-month follow up

Cigarette smoking abstinence from the target quit (allowing for an initial 14-day grace period) to the 3-month follow up, as verified by breath carbon monoxide, urine cotinine, and retrospective self-report.

Outcome measures

Outcome measures
Measure	Nicotine Replacement Therapy (NRT) First, Then Psilocybin-assisted Treatment n=40 Participants Participants will receive a 13-week cognitive behavioral intervention for smoking cessation, with a standard 8 to 10-week regimen of NRT to be administered beginning on the Target Quit Date in week 5. NRT for this study will be a transdermal nicotine patch administered according to recommended label usage (For individuals who smoke more than 10 cigarettes per day: 21mg daily weeks 1-6, 14mg daily weeks 7-8, 7mg daily weeks 9-10. For individuals who smoke 10 or less cigarettes per day: 14mg daily for weeks 1-6, 7mg daily for weeks 7-8). Participants who were initially assigned to the "Nicotine Replacement Therapy (NRT)" Arm/Group had the option to cross-over to "Psilocybin-assisted Treatment" at 6 months.	Psilocybin-assisted Treatment n=42 Participants Participants will receive a 13-week cognitive behavioral intervention for smoking cessation, with a high dose of psilocybin (30mg / 70kg) to be administered on the Target Quit Date in week 5. Psilocybin-assisted treatment: Participants will be administered 30 mg/70 kg psilocybin. Preliminary evidence from our ongoing psilocybin dose-effects study suggests that this dose is associated with mystical-type experiences.	Cross-over to Psilocybin-assisted Treatment Participants in the Nicotine Replacement Therapy (NRT) arm were also eligible to receive a single high-dose (30mg/70kg) psilocybin administration after completing the primary study endpoint at 6-month follow-up. Thus, individuals in this category opted to complete this cross-over psilocybin session after completing a course of NRT.
Prolonged Abstinence: Biologically Verified Cigarette Smoking Abstinence for 3 Months	12 Participants	20 Participants	—

SECONDARY outcome

Timeframe: From the target quit date to the 12-month follow up

Population: Participants with data collected

Cigarette smoking abstinence from the target quit (allowing for an initial 14-day grace period) to the 12-month follow up, as verified by breath carbon monoxide, urine cotinine, and retrospective self-report.

Outcome measures

Outcome measures
Measure	Nicotine Replacement Therapy (NRT) First, Then Psilocybin-assisted Treatment n=14 Participants Participants will receive a 13-week cognitive behavioral intervention for smoking cessation, with a standard 8 to 10-week regimen of NRT to be administered beginning on the Target Quit Date in week 5. NRT for this study will be a transdermal nicotine patch administered according to recommended label usage (For individuals who smoke more than 10 cigarettes per day: 21mg daily weeks 1-6, 14mg daily weeks 7-8, 7mg daily weeks 9-10. For individuals who smoke 10 or less cigarettes per day: 14mg daily for weeks 1-6, 7mg daily for weeks 7-8). Participants who were initially assigned to the "Nicotine Replacement Therapy (NRT)" Arm/Group had the option to cross-over to "Psilocybin-assisted Treatment" at 6 months.	Psilocybin-assisted Treatment n=42 Participants Participants will receive a 13-week cognitive behavioral intervention for smoking cessation, with a high dose of psilocybin (30mg / 70kg) to be administered on the Target Quit Date in week 5. Psilocybin-assisted treatment: Participants will be administered 30 mg/70 kg psilocybin. Preliminary evidence from our ongoing psilocybin dose-effects study suggests that this dose is associated with mystical-type experiences.	Cross-over to Psilocybin-assisted Treatment n=26 Participants Participants in the Nicotine Replacement Therapy (NRT) arm were also eligible to receive a single high-dose (30mg/70kg) psilocybin administration after completing the primary study endpoint at 6-month follow-up. Thus, individuals in this category opted to complete this cross-over psilocybin session after completing a course of NRT.
Prolonged Abstinence: Biologically Verified Cigarette Smoking Abstinence for 12 Months	0 Participants	15 Participants	7 Participants

Adverse Events

Psilocybin-assisted Treatment

Serious events: 0 serious events

Other events: 37 other events

Deaths: 0 deaths

Nicotine Replacement Therapy (NRT)

Serious events: 1 serious events

Other events: 31 other events

Deaths: 0 deaths

Cross-over to Psilocybin-assisted Treatment

Serious events: 1 serious events

Other events: 25 other events

Deaths: 0 deaths

Serious adverse events

Serious adverse events
Measure	Psilocybin-assisted Treatment n=42 participants at risk Participants will receive a 13-week cognitive behavioral intervention for smoking cessation, with a high dose of psilocybin (30mg / 70kg) to be administered on the Target Quit Date in week 5. Psilocybin-assisted treatment: Participants will be administered 30 mg/70 kg psilocybin. Preliminary evidence from our ongoing psilocybin dose-effects study suggests that this dose is associated with mystical-type experiences.	Nicotine Replacement Therapy (NRT) n=40 participants at risk Participants will receive a 13-week cognitive behavioral intervention for smoking cessation, with a standard 8 to 10-week regimen of NRT to be administered beginning on the Target Quit Date in week 5. NRT for this study will be a transdermal nicotine patch administered according to recommended label usage (For individuals who smoke more than 10 cigarettes per day: 21mg daily weeks 1-6, 14mg daily weeks 7-8, 7mg daily weeks 9-10. For individuals who smoke 10 or less cigarettes per day: 14mg daily for weeks 1-6, 7mg daily for weeks 7-8).	Cross-over to Psilocybin-assisted Treatment n=26 participants at risk Participants in the Nicotine Replacement Therapy (NRT) arm were also eligible to receive a single high-dose (30mg/70kg) psilocybin administration after completing the primary study endpoint at 6-month follow-up. Thus, individuals in this category opted to complete this cross-over psilocybin session after completing a course of NRT.
Gastrointestinal disorders Gallstones / gallbladder removal	0.00% 0/42 • Up to 12 months After TQD participants were asked at each study visit about any adverse events (AEs) since their last visit, which were documented, including duration, severity, and relatedness. Participants in the Nicotine Replacement Therapy (NRT) arm were eligible to receive a 30mg/70kg psilocybin session after completing the primary 6-month follow-up. Those who completed this cross-over psilocybin session received 2 interventions (NRT and psilocybin), so their AEs are reported separately.	2.5% 1/40 • Number of events 1 • Up to 12 months After TQD participants were asked at each study visit about any adverse events (AEs) since their last visit, which were documented, including duration, severity, and relatedness. Participants in the Nicotine Replacement Therapy (NRT) arm were eligible to receive a 30mg/70kg psilocybin session after completing the primary 6-month follow-up. Those who completed this cross-over psilocybin session received 2 interventions (NRT and psilocybin), so their AEs are reported separately.	0.00% 0/26 • Up to 12 months After TQD participants were asked at each study visit about any adverse events (AEs) since their last visit, which were documented, including duration, severity, and relatedness. Participants in the Nicotine Replacement Therapy (NRT) arm were eligible to receive a 30mg/70kg psilocybin session after completing the primary 6-month follow-up. Those who completed this cross-over psilocybin session received 2 interventions (NRT and psilocybin), so their AEs are reported separately.
Psychiatric disorders Suicidal Ideation	0.00% 0/42 • Up to 12 months After TQD participants were asked at each study visit about any adverse events (AEs) since their last visit, which were documented, including duration, severity, and relatedness. Participants in the Nicotine Replacement Therapy (NRT) arm were eligible to receive a 30mg/70kg psilocybin session after completing the primary 6-month follow-up. Those who completed this cross-over psilocybin session received 2 interventions (NRT and psilocybin), so their AEs are reported separately.	0.00% 0/40 • Up to 12 months After TQD participants were asked at each study visit about any adverse events (AEs) since their last visit, which were documented, including duration, severity, and relatedness. Participants in the Nicotine Replacement Therapy (NRT) arm were eligible to receive a 30mg/70kg psilocybin session after completing the primary 6-month follow-up. Those who completed this cross-over psilocybin session received 2 interventions (NRT and psilocybin), so their AEs are reported separately.	3.8% 1/26 • Number of events 1 • Up to 12 months After TQD participants were asked at each study visit about any adverse events (AEs) since their last visit, which were documented, including duration, severity, and relatedness. Participants in the Nicotine Replacement Therapy (NRT) arm were eligible to receive a 30mg/70kg psilocybin session after completing the primary 6-month follow-up. Those who completed this cross-over psilocybin session received 2 interventions (NRT and psilocybin), so their AEs are reported separately.

Other adverse events

Additional Information

Dr. Matthew W. Johnson

Sheppard Pratt

Phone: 443 862 0461

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee
Publication restrictions are in place