Trial Outcomes & Findings for Dose Timing of D-Cycloserine to Augment CBT for Social Anxiety Disorder (NCT NCT02066792)
NCT ID: NCT02066792
Last Updated: 2026-06-15
Results Overview
The main outcome was a composite Z-score from the Liebowitz Social Anxiety Scale (LSAS) and the Social Phobic Disorders Severity and Change Form (SPD-SC Form). "The Composite Z-score of the LSAS and SPD-SC Form indicates the number of standard deviations away from the mean. A Z-score of 0 is equal to the mean of a reference population. Negative numbers indicate values lower symptom severity and positive numbers indicate higher symptom severity. The LSAS is a 24-item scale that measures fear and avoidance in social and performance situations within the last week, using 0 (no fear/never avoids) to 3 (severe fear/usually avoids) scale. LSAS scores range from 0-144 with higher scores indicated worse outcomes. The SPD-S is the Clinical Global Impression Scale27 adapted for SAD, which instructs evaluators to use a 7-point scale (1=normal, not at all ill; 7=among the most extremely ill patients) to index the severity of social anxiety.
Recruitment status
COMPLETED
Study phase
EARLY_PHASE1
Target enrollment
152 participants
Primary outcome timeframe
Assessments took place at multiple time points from baseline to 3-month follow-up. The three-month is reported
Results posted on
2026-06-15
Participant Flow
Participant milestones
| Measure |
Tailored Post-Session DCS
Individuals in this condition will receive 5 weeks of CBT for social anxiety disorder and two pills (i.e. one placebo before and one dcs/placebo after the session). Individuals are administered dcs after the session if exposure is determined successful (SUDS below 40). Individuals are administered the placebo is exposure is determined unsuccessful.
The type of pill (i.e. dcs vs. placebo) administered after session is determined after the session.
D-Cycloserine: D-cycloserine is a medication thought to be associated with fear extinction.
Placebo: Sugar pill
|
Pre-Session DCS
Individuals in this condition will receive 5 weeks of CBT for social anxiety disorder and two pills (i.e. one dcs before and one placebo after the session).
D-Cycloserine: D-cycloserine is a medication thought to be associated with fear extinction.
Placebo: Sugar pill
|
Placebo
Individuals in this condition will receive 5 weeks of CBT for social anxiety disorder and two pills (i.e. one placebo before and one placebo after the session).
Placebo: Sugar pill
|
Non-Tailored Post-Session DCS
Individuals in this condition will receive 5 weeks of CBT for social anxiety disorder and two pills (i.e. one placebo before and one dcs after the session).
D-Cycloserine: D-cycloserine is a medication thought to be associated with fear extinction.
Placebo: Sugar pill
|
|---|---|---|---|---|
|
Overall Study
STARTED
|
40
|
38
|
38
|
36
|
|
Overall Study
COMPLETED
|
33
|
33
|
30
|
27
|
|
Overall Study
NOT COMPLETED
|
7
|
5
|
8
|
9
|
Reasons for withdrawal
Withdrawal data not reported
Baseline Characteristics
Dose Timing of D-Cycloserine to Augment CBT for Social Anxiety Disorder
Baseline characteristics by cohort
| Measure |
Tailored Post-Session DCS
n=40 Participants
Individuals in this condition will receive 5 weeks of CBT for social anxiety disorder and two pills (i.e. one placebo before and one dcs/placebo after the session). DCS will be administered if the session is deemed a success.
D-Cycloserine: D-cycloserine is a medication thought to be associated with fear extinction.
Placebo: Sugar pill
|
Pre-Session DCS
n=38 Participants
Individuals in this condition will receive 5 weeks of CBT for social anxiety disorder and two pills (i.e. one dcs before and one placebo after the session).
D-Cycloserine: D-cycloserine is a medication thought to be associated with fear extinction.
Placebo: Sugar pill
|
Placebo
n=38 Participants
Individuals in this condition will receive 5 weeks of CBT for social anxiety disorder and two pills (i.e. one placebo before and one placebo after the session).
Placebo: Sugar pill
|
Non-Tailored Post-Session DCS
n=36 Participants
Individuals in this condition will receive 5 weeks of CBT for social anxiety disorder and two pills (i.e. one placebo before and one dcs after the session).
D-Cycloserine: D-cycloserine is a medication thought to be associated with fear extinction.
Placebo: Sugar pill
|
Total
n=152 Participants
Total of all reporting groups
|
|---|---|---|---|---|---|
|
Age, Categorical
<=18 years
|
0 Participants
n=20 Participants
|
0 Participants
n=20 Participants
|
0 Participants
n=40 Participants
|
0 Participants
n=5 Participants
|
0 Participants
n=9 Participants
|
|
Age, Categorical
Between 18 and 65 years
|
40 Participants
n=20 Participants
|
38 Participants
n=20 Participants
|
38 Participants
n=40 Participants
|
36 Participants
n=5 Participants
|
152 Participants
n=9 Participants
|
|
Age, Categorical
>=65 years
|
0 Participants
n=20 Participants
|
0 Participants
n=20 Participants
|
0 Participants
n=40 Participants
|
0 Participants
n=5 Participants
|
0 Participants
n=9 Participants
|
|
Age, Continuous
|
30.78 Years
STANDARD_DEVIATION 9.88 • n=20 Participants
|
29.73 Years
STANDARD_DEVIATION 10.42 • n=20 Participants
|
28.76 Years
STANDARD_DEVIATION 11.81 • n=40 Participants
|
27.54 Years
STANDARD_DEVIATION 8.29 • n=5 Participants
|
29.20 Years
STANDARD_DEVIATION 10.1 • n=9 Participants
|
|
Sex: Female, Male
Female
|
24 Participants
n=20 Participants
|
22 Participants
n=20 Participants
|
18 Participants
n=40 Participants
|
21 Participants
n=5 Participants
|
85 Participants
n=9 Participants
|
|
Sex: Female, Male
Male
|
16 Participants
n=20 Participants
|
16 Participants
n=20 Participants
|
20 Participants
n=40 Participants
|
15 Participants
n=5 Participants
|
67 Participants
n=9 Participants
|
|
Ethnicity (NIH/OMB)
Hispanic or Latino
|
5 Participants
n=20 Participants
|
6 Participants
n=20 Participants
|
10 Participants
n=40 Participants
|
9 Participants
n=5 Participants
|
30 Participants
n=9 Participants
|
|
Ethnicity (NIH/OMB)
Not Hispanic or Latino
|
33 Participants
n=20 Participants
|
32 Participants
n=20 Participants
|
26 Participants
n=40 Participants
|
25 Participants
n=5 Participants
|
116 Participants
n=9 Participants
|
|
Ethnicity (NIH/OMB)
Unknown or Not Reported
|
2 Participants
n=20 Participants
|
0 Participants
n=20 Participants
|
2 Participants
n=40 Participants
|
2 Participants
n=5 Participants
|
6 Participants
n=9 Participants
|
|
Race (NIH/OMB)
American Indian or Alaska Native
|
0 Participants
n=20 Participants
|
0 Participants
n=20 Participants
|
0 Participants
n=40 Participants
|
0 Participants
n=5 Participants
|
0 Participants
n=9 Participants
|
|
Race (NIH/OMB)
Asian
|
6 Participants
n=20 Participants
|
7 Participants
n=20 Participants
|
8 Participants
n=40 Participants
|
13 Participants
n=5 Participants
|
34 Participants
n=9 Participants
|
|
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
|
0 Participants
n=20 Participants
|
0 Participants
n=20 Participants
|
0 Participants
n=40 Participants
|
0 Participants
n=5 Participants
|
0 Participants
n=9 Participants
|
|
Race (NIH/OMB)
Black or African American
|
8 Participants
n=20 Participants
|
5 Participants
n=20 Participants
|
4 Participants
n=40 Participants
|
3 Participants
n=5 Participants
|
20 Participants
n=9 Participants
|
|
Race (NIH/OMB)
White
|
25 Participants
n=20 Participants
|
23 Participants
n=20 Participants
|
24 Participants
n=40 Participants
|
18 Participants
n=5 Participants
|
90 Participants
n=9 Participants
|
|
Race (NIH/OMB)
More than one race
|
0 Participants
n=20 Participants
|
1 Participants
n=20 Participants
|
2 Participants
n=40 Participants
|
2 Participants
n=5 Participants
|
5 Participants
n=9 Participants
|
|
Race (NIH/OMB)
Unknown or Not Reported
|
1 Participants
n=20 Participants
|
2 Participants
n=20 Participants
|
0 Participants
n=40 Participants
|
0 Participants
n=5 Participants
|
3 Participants
n=9 Participants
|
|
Region of Enrollment
United States
|
40 participants
n=20 Participants
|
38 participants
n=20 Participants
|
38 participants
n=40 Participants
|
36 participants
n=5 Participants
|
152 participants
n=9 Participants
|
PRIMARY outcome
Timeframe: Assessments took place at multiple time points from baseline to 3-month follow-up. The three-month is reportedPopulation: Intent-to-treat
The main outcome was a composite Z-score from the Liebowitz Social Anxiety Scale (LSAS) and the Social Phobic Disorders Severity and Change Form (SPD-SC Form). "The Composite Z-score of the LSAS and SPD-SC Form indicates the number of standard deviations away from the mean. A Z-score of 0 is equal to the mean of a reference population. Negative numbers indicate values lower symptom severity and positive numbers indicate higher symptom severity. The LSAS is a 24-item scale that measures fear and avoidance in social and performance situations within the last week, using 0 (no fear/never avoids) to 3 (severe fear/usually avoids) scale. LSAS scores range from 0-144 with higher scores indicated worse outcomes. The SPD-S is the Clinical Global Impression Scale27 adapted for SAD, which instructs evaluators to use a 7-point scale (1=normal, not at all ill; 7=among the most extremely ill patients) to index the severity of social anxiety.
Outcome measures
| Measure |
Tailored Post-Session DCS
n=40 Participants
Individuals in this condition will receive 5 weeks of CBT for social anxiety disorder and two pills (i.e. one placebo before and one dcs/placebo after the session). Individuals are administered dcs after the session if exposure is determined successful (SUDS below 40). Individuals are administered the placebo is exposure is determined unsuccessful.
The type of pill (i.e. dcs vs. placebo) administered after session is determined after the session.
D-Cycloserine: D-cycloserine is a medication thought to be associated with fear extinction.
Placebo: Sugar pill
|
Pre-Session DCS
n=38 Participants
Individuals in this condition will receive 5 weeks of CBT for social anxiety disorder and two pills (i.e. one dcs before and one placebo after the session).
D-Cycloserine: D-cycloserine is a medication thought to be associated with fear extinction.
Placebo: Sugar pill
|
Placebo
n=38 Participants
Individuals in this condition will receive 5 weeks of CBT for social anxiety disorder and two pills (i.e. one placebo before and one placebo after the session).
Placebo: Sugar pill
|
Non-Tailored Post-Session DCS
n=36 Participants
Individuals in this condition will receive 5 weeks of CBT for social anxiety disorder and two pills (i.e. one placebo before and one dcs after the session).
D-Cycloserine: D-cycloserine is a medication thought to be associated with fear extinction.
Placebo: Sugar pill
|
|---|---|---|---|---|
|
Social Anxiety Symptom Severity
|
-.46 score on a scale
Standard Error .13
|
-.90 score on a scale
Standard Error .13
|
-.39 score on a scale
Standard Error .14
|
-.88 score on a scale
Standard Error .14
|
Adverse Events
Tailored Post-Session DCS
Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths
Pre-Session DCS
Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths
Placebo
Serious events: 1 serious events
Other events: 0 other events
Deaths: 0 deaths
Non-Tailored Post-Session DCS
Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths
Serious adverse events
| Measure |
Tailored Post-Session DCS
n=40 participants at risk
Individuals in this condition will receive 5 weeks of CBT for social anxiety disorder and two pills (i.e. one placebo before and one dcs/placebo after the session). DCS will be administered if the session is deemed a success.
D-Cycloserine: D-cycloserine is a medication thought to be associated with fear extinction.
Placebo: Sugar pill
|
Pre-Session DCS
n=38 participants at risk
Individuals in this condition will receive 5 weeks of CBT for social anxiety disorder and two pills (i.e. one dcs before and one placebo after the session).
D-Cycloserine: D-cycloserine is a medication thought to be associated with fear extinction.
Placebo: Sugar pill
|
Placebo
n=38 participants at risk
Individuals in this condition will receive 5 weeks of CBT for social anxiety disorder and two pills (i.e. one placebo before and one placebo after the session).
Placebo: Sugar pill
|
Non-Tailored Post-Session DCS
n=36 participants at risk
Individuals in this condition will receive 5 weeks of CBT for social anxiety disorder and two pills (i.e. one placebo before and one dcs after the session).
D-Cycloserine: D-cycloserine is a medication thought to be associated with fear extinction.
Placebo: Sugar pill
|
|---|---|---|---|---|
|
Psychiatric disorders
Serious Adverse Event
|
0.00%
0/40 • Data for adverse events was collected at each assessment point over the course of the study (e.g., in-person screening, baseline appointment, sessions 1-5, and the 1-week, 1-month, and 3-month follow-ups).
Participants were asked if they had experienced any injuries or illnesses at the beginning of each study visit.
|
0.00%
0/38 • Data for adverse events was collected at each assessment point over the course of the study (e.g., in-person screening, baseline appointment, sessions 1-5, and the 1-week, 1-month, and 3-month follow-ups).
Participants were asked if they had experienced any injuries or illnesses at the beginning of each study visit.
|
2.6%
1/38 • Data for adverse events was collected at each assessment point over the course of the study (e.g., in-person screening, baseline appointment, sessions 1-5, and the 1-week, 1-month, and 3-month follow-ups).
Participants were asked if they had experienced any injuries or illnesses at the beginning of each study visit.
|
0.00%
0/36 • Data for adverse events was collected at each assessment point over the course of the study (e.g., in-person screening, baseline appointment, sessions 1-5, and the 1-week, 1-month, and 3-month follow-ups).
Participants were asked if they had experienced any injuries or illnesses at the beginning of each study visit.
|
Other adverse events
Adverse event data not reported
Additional Information
Dr. Jasper Smits
Institute for Mental Health Research and Department of Psychology, The University of Texas at Austin
Phone: 512-475-8095
Email: [email protected]
Results disclosure agreements
- Principal investigator is a sponsor employee
- Publication restrictions are in place