Trial Outcomes & Findings for Effects of Varenicline on Brain Activity During Nicotine Abstinence (NCT NCT00602927)
NCT ID: NCT00602927
Last Updated: 2011-05-10
Results Overview
We calculated the percent BOLD signal change while performing the N-back task between the varenicline vs. placebo session. We subtracted BOLD signal observed during the 0-back condition from the BOLD signal observed during the 3-back condition (3back minus 0-back)We controlled for relevant co-variates such as sex, nicotine dependence level and education.
COMPLETED
NA
38 participants
Day 13
2011-05-10
Participant Flow
Participants were recruited from mass media advertising in the greater Philadelphia area from November 2007 - June 2008.
All participants completed a 14 day wash-out period between the two study phases. They were instructed to resume their usual smoking behavior in this wash-out phase.
Participant milestones
| Measure |
Placebo First, Then Varenicline
Days 1 - 3: 0.5 mg once a day orally Days 4 - 7: 0.5 mg twice a day orally Days 8 - 13: 1 mg twice a day orally
|
Varenicline First, Then Placebo
Days 1 - 3: 0.5 mg once a day orally Days 4 - 7: 0.5 mg twice a day orally Days 8 - 13: 1 mg twice a day orally
|
|---|---|---|
|
Period 1: 13 Days
STARTED
|
19
|
19
|
|
Period 1: 13 Days
COMPLETED
|
15
|
14
|
|
Period 1: 13 Days
NOT COMPLETED
|
4
|
5
|
|
Period 2: 14 Days
STARTED
|
15
|
14
|
|
Period 2: 14 Days
COMPLETED
|
15
|
12
|
|
Period 2: 14 Days
NOT COMPLETED
|
0
|
2
|
|
Period 3: 13 Days
STARTED
|
15
|
12
|
|
Period 3: 13 Days
COMPLETED
|
13
|
9
|
|
Period 3: 13 Days
NOT COMPLETED
|
2
|
3
|
Reasons for withdrawal
| Measure |
Placebo First, Then Varenicline
Days 1 - 3: 0.5 mg once a day orally Days 4 - 7: 0.5 mg twice a day orally Days 8 - 13: 1 mg twice a day orally
|
Varenicline First, Then Placebo
Days 1 - 3: 0.5 mg once a day orally Days 4 - 7: 0.5 mg twice a day orally Days 8 - 13: 1 mg twice a day orally
|
|---|---|---|
|
Period 1: 13 Days
Protocol Violation
|
2
|
4
|
|
Period 1: 13 Days
MRI scanner technical issue
|
1
|
0
|
|
Period 1: 13 Days
Time
|
1
|
0
|
|
Period 1: 13 Days
Claustrophobia
|
0
|
1
|
|
Period 2: 14 Days
Protocol Violation
|
0
|
2
|
|
Period 3: 13 Days
Protocol Violation
|
0
|
1
|
|
Period 3: 13 Days
MRI data quality
|
2
|
2
|
Baseline Characteristics
Effects of Varenicline on Brain Activity During Nicotine Abstinence
Baseline characteristics by cohort
| Measure |
Placebo First, Then Varenicline
n=19 Participants
Days 1 - 3: 0.5 mg once a day orally Days 4 - 7: 0.5 mg twice a day orally Days 8 - 13: 1 mg twice a day orally
|
Varenicline First, Then Placebo
n=19 Participants
Days 1 - 3: 0.5 mg once a day orally Days 4 - 7: 0.5 mg twice a day orally Days 8 - 13: 1 mg twice a day orally
|
Total
n=38 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
|
19 Participants
n=5 Participants
|
19 Participants
n=7 Participants
|
38 Participants
n=5 Participants
|
|
Age, Categorical
>=65 years
|
0 Participants
n=5 Participants
|
0 Participants
n=7 Participants
|
0 Participants
n=5 Participants
|
|
Age Continuous
|
41.05 years
STANDARD_DEVIATION 13.32 • n=5 Participants
|
39.79 years
STANDARD_DEVIATION 12.68 • n=7 Participants
|
40.42 years
STANDARD_DEVIATION 12.84 • n=5 Participants
|
|
Sex: Female, Male
Female
|
9 Participants
n=5 Participants
|
10 Participants
n=7 Participants
|
19 Participants
n=5 Participants
|
|
Sex: Female, Male
Male
|
10 Participants
n=5 Participants
|
9 Participants
n=7 Participants
|
19 Participants
n=5 Participants
|
|
Region of Enrollment
United States
|
19 participants
n=5 Participants
|
19 participants
n=7 Participants
|
38 participants
n=5 Participants
|
PRIMARY outcome
Timeframe: Day 13Population: Participants who completed both study phases were included in the analyses (n=25). Additional participants (n=3) were excluded due to measurement artifact.
We calculated the percent BOLD signal change while performing the N-back task between the varenicline vs. placebo session. We subtracted BOLD signal observed during the 0-back condition from the BOLD signal observed during the 3-back condition (3back minus 0-back)We controlled for relevant co-variates such as sex, nicotine dependence level and education.
Outcome measures
| Measure |
Placebo
n=22 Participants
Days 1 - 3: 0.5 mg once a day orally Days 4 - 7: 0.5 mg twice a day orally Days 8 - 13: 1 mg twice a day orally
|
Varenicline
n=22 Participants
Days 1 - 3: 0.5 mg once a day orally Days 4 - 7: 0.5 mg twice a day orally Days 8 - 13: 1 mg twice a day orally
|
|---|---|---|
|
Percent Change BOLD Signal
|
0.48 BOLD Signal Change (3-back minus 0-back)
Standard Error 0.05
|
0.61 BOLD Signal Change (3-back minus 0-back)
Standard Error 0.03
|
SECONDARY outcome
Timeframe: Day 13Population: Participants who completed both study phases were included in the analysis. Other participants (n=3) were excluded due to measurement artifact.
We examined the difference in correct reaction time on the N-back task between varenicline and placebo treatment. Models included terms for the main effect of treatment period (varenicline vs. placebo), memory load (0-back, 1-back, 2-back, 3-back) and covariates. We tested for interactions between nicotine dependence severity and treatment.
Outcome measures
| Measure |
Placebo
n=22 Participants
Days 1 - 3: 0.5 mg once a day orally Days 4 - 7: 0.5 mg twice a day orally Days 8 - 13: 1 mg twice a day orally
|
Varenicline
n=22 Participants
Days 1 - 3: 0.5 mg once a day orally Days 4 - 7: 0.5 mg twice a day orally Days 8 - 13: 1 mg twice a day orally
|
|---|---|---|
|
Effect of Varenicline Treatment on Task Performance (N-back Correct Response Time)
|
692.14 Milliseconds
Standard Deviation 128.57
|
637.99 Milliseconds
Standard Deviation 164.30
|
Adverse Events
Placebo First, Then Varenicline
Varenicline First, Then Placebo
Serious adverse events
Adverse event data not reported
Other adverse events
| Measure |
Placebo First, Then Varenicline
n=19 participants at risk
Days 1 - 3: 0.5 mg once a day orally Days 4 - 7: 0.5 mg twice a day orally Days 8 - 13: 1 mg twice a day orally
|
Varenicline First, Then Placebo
n=19 participants at risk
Days 1 - 3: 0.5 mg once a day orally Days 4 - 7: 0.5 mg twice a day orally Days 8 - 13: 1 mg twice a day orally
|
|---|---|---|
|
General disorders
Severe Lethargy
|
0.00%
0/19 • Day 13
|
5.3%
1/19 • Number of events 1 • Day 13
|
Additional Information
Results disclosure agreements
- Principal investigator is a sponsor employee
- Publication restrictions are in place