The Cognitive Enhancing Effects of D-Cycloserine Among Non-Demented Elderly

NCT01361633, Phase 2, Completed, Hartford Hospital; results first posted 2012-06-21

Trial 12

As registered on ClinicalTrials.gov, in the graph's capture of the registry.

Field	Value	Source
Title	The Cognitive Enhancing Effects of D-Cycloserine Among Non-Demented Elderly	ClinicalTrials.gov
NCT number	NCT01361633	ClinicalTrials.gov
Status	Completed	ClinicalTrials.gov
Phases	Phase 2	ClinicalTrials.gov
Enrollment	51 participants, actual	ClinicalTrials.gov
Lead sponsor	Hartford Hospital	ClinicalTrials.gov
Conditions	Treatment, Placebo	ClinicalTrials.gov
Interventions	d-cycloserine, Sugar Pill	ClinicalTrials.gov
First posted	2011-05-27	ClinicalTrials.gov
Last updated	2021-02-18	ClinicalTrials.gov
Results first posted	2012-06-21	ClinicalTrials.gov
Limitations and caveats	DCS dosing was 1 hour prior to testing, rather than 4-8; the sample had homogenous cognitive capabilities; repeatedly administering DCS may have enhanced cognitive functioning; the measures may not have adequately tapped hippocampal-based learning.	ClinicalTrials.gov

Registered outcomes 7

Each outcome the trial registered, primary first, in ClinicalTrials.gov's words.

List	Outcome	Time frame	Description	Source
Primary	California Verbal Learning Test-II (CLVT-II)	Outcome measures will be collected during a single neuropsychological testing administration lasting approximately 3 hours without patient follow up. Scores for the experimental and control group were compared.	The CLVT-II is an assessment of verbal learning and memory which measures recall and recognition scores, encoding strategies, learning rates and error types. A list learning task with 16 words from 4 semantic categories are read over a series of 5 list presentations. Recall is assessed after learning and at a 20-minute delay. Software produces a report that computes raw and standardized scores. Our dependent variable was the age adjusted t-score for total number of words recalled after 5 trials. A higher score indicated better recall. The maximum possible score was 80 and a minimum was 0.	ClinicalTrials.gov
Secondary	Continuous Performance Test	Outcome measures will be collected during a single neuropsychological testing administration lasting approximately 3 hours without further patient follow-up	Sustained attention was assessed using the Penn version of the Continuous Performance Test. During the CPT the participant responds to a target stimulus (e.g., the letter "A"), while inhibiting responding to distractor stimuli. Reaction time to correct targets (true positives) was used as the dependent variable. Faster reaction times indicate better performance.	ClinicalTrials.gov
Secondary	Controlled Oral Word Association Test	Outcome measures will be collected during a single neuropsychological testing administration lasting approximately 3 hours without further patient follow-up	The Controlled Oral Word Association Test is a measure of the ability to orally generate words to a phonemic cue within a 60-second time interval. Age and education-adjusted t-scores were used as the dependent variable. A T-score of 50 is equal to the mean, with a standard deviation of 10 points. A higher T-score is a more favorable outcome.	ClinicalTrials.gov
Secondary	Wisconsin Card Sort Test	Outcome measures will be collected during a single neuropsychological testing administration lasting approximately 3 hours without further patient follow-up	The Wisconsin Card Sorting Test is a test of rule-learning and conceptual flexibility. The participant is required to learn to sort a series of cards according to one of three principles (color, form or number) based on response feedback. The age-adjusted t-score for total number of errors was used as a dependent variable. A T-score of 50 is equal to the mean, with a standard deviation of 10 points. A higher T-score is a more favorable outcome.	ClinicalTrials.gov
Secondary	Trails B	Outcome measures will be collected during a single neuropsychological testing administration lasting approximately 3 hours without further patient follow-up	Trails B is a measure of cognitive flexibility. The participant alternates sequencing between numbers and letters. An age and education-adjusted t-score for time to complete the exercise was used as the dependent variable. A T-score of 50 is equal to the mean, with a standard deviation of 10 points. A higher T-score is a more favorable outcome.	ClinicalTrials.gov
Secondary	Stroop	Outcome measures will be collected during a single neuropsychological testing administration lasting approximately 3 hours without further patient follow-up	The Stroop Color Word Test is a measure of selective attention and cognitive flexibility. This measure consists of three conditions: word reading, color naming and color-word naming. The interference score (t-score) was used as the dependent variable. A T-score of 50 is equal to the mean, with a standard deviation of 10 points. Higher t-scores represent a more favorable outcome.	ClinicalTrials.gov
Secondary	Implicit Memory Task	Outcome measures will be collected during a single neuropsychological testing administration lasting approximately 3 hours without further patient follow-up	Participants were presented with 32 stimulus words: 16 neutral and 16 threatening words. After a filler task (crossing out 8's on a sheet of randomized numbers) participants completed a response sheet including the stems for the 32 words presented to participants (primed words) along with stems for the 32 unprimed words. Participants were instructed to write down the first word that came to mind that completes each word stem. The priming effect was determined using the difference score between the correct number of stem completions for primed versus unprimed words. This is a value determined for each participant using the following equation: correct number of stem completions for primed word minus the correct number of stem completions for unprimed words. A larger difference score indicates a stronger implicit memory.	ClinicalTrials.gov

Outcomes 7

Each outcome the trial posted results for, in ClinicalTrials.gov's words.

Type	Outcome	Time frame	Population	Units	Measured as	Source
PRIMARY	California Verbal Learning Test-II (CLVT-II)	Outcome measures will be collected during a single neuropsychological testing administration lasting approximately 3 hours without patient follow up. Scores for the experimental and control group were compared.		age adjusted t-scores	MEAN	ClinicalTrials.gov
SECONDARY	Continuous Performance Test	Outcome measures will be collected during a single neuropsychological testing administration lasting approximately 3 hours without further patient follow-up		milliseconds	MEAN	ClinicalTrials.gov
SECONDARY	Controlled Oral Word Association Test	Outcome measures will be collected during a single neuropsychological testing administration lasting approximately 3 hours without further patient follow-up		t-scores	MEAN	ClinicalTrials.gov
SECONDARY	Wisconsin Card Sort Test	Outcome measures will be collected during a single neuropsychological testing administration lasting approximately 3 hours without further patient follow-up	sample size for DCS group is n = 18 owing to missing data from one participant.	t scores	MEAN	ClinicalTrials.gov
SECONDARY	Trails B	Outcome measures will be collected during a single neuropsychological testing administration lasting approximately 3 hours without further patient follow-up		t-scores	MEAN	ClinicalTrials.gov
SECONDARY	Stroop	Outcome measures will be collected during a single neuropsychological testing administration lasting approximately 3 hours without further patient follow-up		t-score	MEAN	ClinicalTrials.gov
SECONDARY	Implicit Memory Task	Outcome measures will be collected during a single neuropsychological testing administration lasting approximately 3 hours without further patient follow-up		correct stem completions	MEAN	ClinicalTrials.gov

Results by group 14

Each measurement the trial posted, group by group, in the words and numbers it posted.

Outcome	Group	Value	Spread	Units	Source
California Verbal Learning Test-II (CLVT-II)	Medication	55.84	Standard Deviation 10.37	age adjusted t-scores	ClinicalTrials.gov
California Verbal Learning Test-II (CLVT-II)	Sugar Pill	55.39	Standard Deviation 10.73	age adjusted t-scores	ClinicalTrials.gov
Continuous Performance Test	Medication	479.50	Standard Deviation 42.43	milliseconds	ClinicalTrials.gov
Continuous Performance Test	Sugar Pill	507.80	Standard Deviation 77.83	milliseconds	ClinicalTrials.gov
Controlled Oral Word Association Test	Medication	49.58	Standard Deviation 9.31	t-scores	ClinicalTrials.gov
Controlled Oral Word Association Test	Sugar Pill	46.91	Standard Deviation 8.14	t-scores	ClinicalTrials.gov
Wisconsin Card Sort Test	Medication	53.50	Standard Deviation 12.37	t scores	ClinicalTrials.gov
Wisconsin Card Sort Test	Sugar Pill	53.70	Standard Deviation 10.73	t scores	ClinicalTrials.gov
Trails B	Medication	52.16	Standard Deviation 10.99	t-scores	ClinicalTrials.gov
Trails B	Sugar Pill	48.83	Standard Deviation 9.38	t-scores	ClinicalTrials.gov
Stroop	Medication	44.68	Standard Deviation 7.17	t-score	ClinicalTrials.gov
Stroop	Sugar Pill	43.30	Standard Deviation 6.67	t-score	ClinicalTrials.gov
Implicit Memory Task	Medication	3.16	Standard Deviation 3.24	correct stem completions	ClinicalTrials.gov
Implicit Memory Task	Sugar Pill	2.00	Standard Deviation 3.43	correct stem completions	ClinicalTrials.gov

Participant flow 6

How many started, completed or left each group, period by period.

Period	Milestone	Group	Participants	Source
Overall Study	STARTED	Medication	25	ClinicalTrials.gov
Overall Study	STARTED	Sugar Pill	26	ClinicalTrials.gov
Overall Study	COMPLETED	Medication	19	ClinicalTrials.gov
Overall Study	COMPLETED	Sugar Pill	23	ClinicalTrials.gov
Overall Study	NOT COMPLETED	Medication	6	ClinicalTrials.gov
Overall Study	NOT COMPLETED	Sugar Pill	3	ClinicalTrials.gov

Adverse events 6

Each adverse event the trial posted, group by group: the participants affected out of those at risk.

Type	Event	Organ system	Group	Affected	At risk	Events	Source
other	Drowsiness	General disorders	Medication	2	19	2	ClinicalTrials.gov
other	Drowsiness	General disorders	Sugar Pill	4	23	4	ClinicalTrials.gov
other	Tingling sensation	General disorders	Medication	0	19	0	ClinicalTrials.gov
other	Tingling sensation	General disorders	Sugar Pill	1	23	1	ClinicalTrials.gov
other	Feeling lightheaded	General disorders	Medication	1	19	1	ClinicalTrials.gov
other	Feeling lightheaded	General disorders	Sugar Pill	0	23	0	ClinicalTrials.gov

Adverse event totals 6

The totals the trial posted for each group.

Total	Group	Affected	At risk	Source
Total, all-cause mortality	Medication			ClinicalTrials.gov
Total, all-cause mortality	Sugar Pill			ClinicalTrials.gov
Total, other adverse events	Medication	3	19	ClinicalTrials.gov
Total, other adverse events	Sugar Pill	4	23	ClinicalTrials.gov
Total, serious adverse events	Medication	0	19	ClinicalTrials.gov
Total, serious adverse events	Sugar Pill	0	23	ClinicalTrials.gov

Papers 0

The papers the trial lists on ClinicalTrials.gov.

PMID	Listed as	Source

Grants 0

The grants NIH RePORTER links to the trial, newest funded first: NIH's, and some of AHRQ's, CDC's, FDA's and VA's. Each shows its title, principal investigators, organization and funder in its newest year.

Project	Title	Principal investigators	Organization	Funder	Fiscal years	Source

Trial comparisons 1

Comparisons of the trial's two groups, calculated by ConductScience from the counts it posted.

Comparison	Source
Medication vs Sugar Pill: serious adverse events	Trial comparisons

Tests 6

The ConductCognition tests this trial's registered outcomes name, as ScienceGraph matched them in trial-tests-2026-11-12-0.2.1.

Test	Named as	Source
Verbal Learning	Primary outcome	ConductCognition
Card Sorting Test (Berg)	Secondary outcome	ConductCognition
Continuous Performance Test	Secondary outcome	ConductCognition
Stroop Color-Word Test	Secondary outcome	ConductCognition
Trail Making Test B	Secondary outcome	ConductCognition
Verbal Fluency	Secondary outcome	ConductCognition

Source 5

Field	Value	Source
Release	trials-2026-11-12-0.4.0	ClinicalTrials.gov
Release manifest SHA-256	0f4a8d8c48aee2a7573ae0fa94ecbeab70c1adbe449bbc95c424bc7d3e97b9d4	ClinicalTrials.gov
Registry capture	2026-11-12	ClinicalTrials.gov
Results copy, AACT	2026-03-23	ClinicalTrials.gov
NIH clinical studies file	2026-11-13	ClinicalTrials.gov

The same record as JSON

Release trials-2026-11-12-0.4.0

ClinicalTrials.gov's posted results, through CTTI's AACT: ClinicalTrials.gov data via Aggregate Analysis of ClinicalTrials.gov (AACT), CTTI. CTTI makes its materials freely available and requests acknowledgement. https://aact.ctti-clinicaltrials.org/documentation/299 ClinicalTrials.gov's data carry an international copyright outside the United States: https://clinicaltrials.gov/about-site/terms-conditions.

ClinicalTrials.gov: none stated ClinicalTrials.gov's data carry an international copyright outside the United States: https://clinicaltrials.gov/about-site/terms-conditions.

NIH RePORTER's clinical studies and project files: Public domain (NIH RePORTER)