Trial Outcomes & Findings for D-Cycloserine to Enhance Cognitive Behavioral Therapy (CBT) for Acrophobia (NCT NCT01102803)
NCT ID: NCT01102803
Last Updated: 2013-02-21
Results Overview
Self-report measure that assesses fear and avoidance of a variety of heights situations. This questionnaire (Cohen, 1977) describes 20 situations and assesses levels of avoidance (0-3) and anxiety (0-6). These scales widely used measure of acrophobia with adequate retest reliability (r = .82-.86) and validity (Baker et al., 1973). Higher scores indicate higher levels of avoidance/anxiety (i.e., worse outcome). All subscales are summed for a total score. AAVQ will be assessed at each visit throughout the 2 month protocol. The minimum score is 0, the maximum is 90.
COMPLETED
PHASE3
40 participants
2 months
2013-02-21
Participant Flow
Participants (N = 29; Mean age = 33.38) with acrophobia were recruited from Southern Methodist University and the greater Dallas area from 2009 to 2011.
76 individuals were assessed for eligibility, of which 47 were excluded due to not having a diagnosis of acrophobia (n=37) or declining participation (n=10). 29 individuals were randomized and no participants were excluded after enrollment but prior to group assignment.
Participant milestones
| Measure |
Sugar Pill
Participants will receive sugar pill placebo augmented cognitive behavioral therapy
|
D-Cycloserine
Participants will receive D-Cycloserine (50mg) augmented cognitive behavioral therapy
|
|---|---|---|
|
Baseline to Post-Treatment
STARTED
|
14
|
15
|
|
Baseline to Post-Treatment
COMPLETED
|
11
|
15
|
|
Baseline to Post-Treatment
NOT COMPLETED
|
3
|
0
|
|
Post to Follow-Up
STARTED
|
11
|
15
|
|
Post to Follow-Up
COMPLETED
|
10
|
12
|
|
Post to Follow-Up
NOT COMPLETED
|
1
|
3
|
Reasons for withdrawal
| Measure |
Sugar Pill
Participants will receive sugar pill placebo augmented cognitive behavioral therapy
|
D-Cycloserine
Participants will receive D-Cycloserine (50mg) augmented cognitive behavioral therapy
|
|---|---|---|
|
Baseline to Post-Treatment
Lost to Follow-up
|
3
|
0
|
|
Post to Follow-Up
Lost to Follow-up
|
1
|
3
|
Baseline Characteristics
D-Cycloserine to Enhance Cognitive Behavioral Therapy (CBT) for Acrophobia
Baseline characteristics by cohort
| Measure |
Sugar Pill
n=14 Participants
Participants will receive sugar pill placebo augmented cognitive behavioral therapy
|
D-Cycloserine
n=15 Participants
Participants will receive D-Cycloserine (50mg) augmented cognitive behavioral therapy
|
Total
n=29 Participants
Total of all reporting groups
|
|---|---|---|---|
|
Age, Categorical
<=18 years
|
0 Participants
n=93 Participants
|
0 Participants
n=4 Participants
|
0 Participants
n=27 Participants
|
|
Age, Categorical
Between 18 and 65 years
|
14 Participants
n=93 Participants
|
15 Participants
n=4 Participants
|
29 Participants
n=27 Participants
|
|
Age, Categorical
>=65 years
|
0 Participants
n=93 Participants
|
0 Participants
n=4 Participants
|
0 Participants
n=27 Participants
|
|
Age Continuous
|
37.71 years
STANDARD_DEVIATION 16.81 • n=93 Participants
|
29.33 years
STANDARD_DEVIATION 14.67 • n=4 Participants
|
33.8 years
STANDARD_DEVIATION 15.74 • n=27 Participants
|
|
Sex: Female, Male
Female
|
10 Participants
n=93 Participants
|
10 Participants
n=4 Participants
|
20 Participants
n=27 Participants
|
|
Sex: Female, Male
Male
|
4 Participants
n=93 Participants
|
5 Participants
n=4 Participants
|
9 Participants
n=27 Participants
|
|
Region of Enrollment
United States
|
14 participants
n=93 Participants
|
15 participants
n=4 Participants
|
29 participants
n=27 Participants
|
PRIMARY outcome
Timeframe: 2 monthsSelf-report measure that assesses fear and avoidance of a variety of heights situations. This questionnaire (Cohen, 1977) describes 20 situations and assesses levels of avoidance (0-3) and anxiety (0-6). These scales widely used measure of acrophobia with adequate retest reliability (r = .82-.86) and validity (Baker et al., 1973). Higher scores indicate higher levels of avoidance/anxiety (i.e., worse outcome). All subscales are summed for a total score. AAVQ will be assessed at each visit throughout the 2 month protocol. The minimum score is 0, the maximum is 90.
Outcome measures
| Measure |
DCS+CBT Treatment
n=15 Participants
Participants receiving DCS augmented CBT
|
Placebo+CBT Treatment
n=14 Participants
Participants receiving PL augmented CBT
|
|---|---|---|
|
Acrophobia Questionnaire With Avoidance (AAVQ)
|
9.00 units on a scale
Standard Deviation 7.41
|
12.38 units on a scale
Standard Deviation 9.72
|
SECONDARY outcome
Timeframe: 2 monthsSelf-report measures that assesses thoughts and feelings towards heights situations. This questionnaire (Abelson and Curtis, 1989) includes six heights situations and assesses attitudes toward these situations using a 0-10 scale. Higher scores indicate a worse outcome and total scores are summed over subscales. Will be assessed at each visit throughout the 2 month protocol. The minimum score is a 0; the maximum is a 60.
Outcome measures
| Measure |
DCS+CBT Treatment
n=15 Participants
Participants receiving DCS augmented CBT
|
Placebo+CBT Treatment
n=14 Participants
Participants receiving PL augmented CBT
|
|---|---|---|
|
Attitudes Towards Heights Questionnaire (ATHQ)
|
45.67 units on a scale
Standard Deviation 8.53
|
47.71 units on a scale
Standard Deviation 12.98
|
SECONDARY outcome
Timeframe: 2 monthsClinician-rated measure of improvement in acrophobia symptoms and severity. Will be assessed at each visit throughout the 2 month protocol. The CGI-S and CGI-I are widely used measures of global psychopathology severity and improvement initially developed for the study of psychotropic drugs (Guy, 1970). In order to obtain CGI ratings, the therapists (blind to study condition) interviewed the participant and used the SCID (including the specific phobia module) as well as the additional measures of acrophobia symptoms (BAT, AAQ, AAVQ, and ATHQ). In the current study, response was defined as either "very much improved" or "much improved" on CGI-I (score ≤ 2). Remission was defined as either "normal" or "minimally ill" on CGI-S (score ≤ 2). The minimum rating is a 1 and the highest is a 7. Lower scores indicate a better outcome.
Outcome measures
| Measure |
DCS+CBT Treatment
n=15 Participants
Participants receiving DCS augmented CBT
|
Placebo+CBT Treatment
n=14 Participants
Participants receiving PL augmented CBT
|
|---|---|---|
|
Clinical Global Improvement Scale (CGI)
|
2.27 units on a scale
Standard Deviation .96
|
2.00 units on a scale
Standard Deviation .89
|
SECONDARY outcome
Timeframe: 2 monthsDuring the initial screen, at post-treatment, and at follow-up, participants underwent a behavioral avoidance test in the virtual reality height environment. Participants reported on a 0-100 scale (100 being the most intense fear) their SUDS for floors 1, 2, 3, 4, 9, 19 of the virtual glass elevator and balconies. This test has been used successfully as a measure of treatment gains in previous studies of acrophobia research (Ressler et al., 2004). For the outcome analyses, we included the level of fear reported at the highest floor of the virtual elevator environment (19th floor). Higher scores indicate a worse outcome.
Outcome measures
| Measure |
DCS+CBT Treatment
n=15 Participants
Participants receiving DCS augmented CBT
|
Placebo+CBT Treatment
n=14 Participants
Participants receiving PL augmented CBT
|
|---|---|---|
|
Behavioral Avoidance Test (BAT)
|
29.73 units on a scale
Standard Deviation 25.67
|
35.55 units on a scale
Standard Deviation 25.18
|
Adverse Events
DCS+CBT
Pill Placebo + CBT
Serious adverse events
Adverse event data not reported
Other adverse events
Adverse event data not reported
Additional Information
Results disclosure agreements
- Principal investigator is a sponsor employee
- Publication restrictions are in place