Trial Outcomes & Findings for Buspirone for the Treatment of Traumatic Brain Injury (TBI) Irritability and Aggression (NCT NCT01821690)
NCT ID: NCT01821690
Last Updated: 2026-02-24
Results Overview
Neuropsychiatric Inventory (NPI) is a 40-item instrument evaluating 12 behavioral domains with prior use in TBI. NPI-Irritability domain (NPI-I) encompasses temper outbursts, mood fluctuations, abrupt anger, impatience, irritable disposition, and argumentative behavior. Assessment involves identifying if these behaviors are present and then scoring the most concerning manifestation on severity (1=mild to 3=severe) and frequency (1-4 scale, higher=greater occurrence). Domain totals (0-12 range) represent the product of severity and frequency ratings for the predominant symptom.
COMPLETED
PHASE4
81 participants
Day 91
2026-02-24
Participant Flow
Recruitment occurred from May 2013 through September 2025 via support groups, physician correspondence, clinical referrals, and newsletters.
Subject's observers were not enrolled.
Participant milestones
| Measure |
Buspirone Treatment
Buspirone starting at 15 mg/day and titrated up to 60 mg/day as prescribed and tolerated. Buspirone used flexible-dose, response-guided titration starting at 15 mg daily, titrated up to 60 mg daily in divided doses. On Day 8, dose automatically increased to 30 mg daily. Dose increased by 15 mg increments at days 35 and 63 if observer-rated NPI-Irritability had not decreased by ≥80% from baseline; dose maintained if ≥80% decrease achieved.
|
Buspirone Placebo
Placebo tablets as prescribed. Buspirone and placebo were identically matched in container labeling, appearance, and sensory properties. Placebo participants underwent identical sham titration.
|
|---|---|---|
|
Overall Study
STARTED
|
41
|
40
|
|
Overall Study
COMPLETED
|
38
|
40
|
|
Overall Study
NOT COMPLETED
|
3
|
0
|
Reasons for withdrawal
Withdrawal data not reported
Baseline Characteristics
Buspirone for the Treatment of Traumatic Brain Injury (TBI) Irritability and Aggression
Baseline characteristics by cohort
| Measure |
Buspirone Treatment
n=41 Participants
starting at 15 mg/day and ending at 60 mg/day as prescribed
|
Buspirone Placebo
n=40 Participants
placebo tablets as prescribed
|
Total
n=81 Participants
Total of all reporting groups
|
|---|---|---|---|
|
Age, Continuous
|
41.5 years
STANDARD_DEVIATION 14.0 • n=58 Participants
|
40.2 years
STANDARD_DEVIATION 14.3
|
40.9 years
STANDARD_DEVIATION 14.1 • n=1 Participants
|
|
Sex: Female, Male
Female
|
14 Participants
n=58 Participants
|
12 Participants
|
26 Participants
n=1 Participants
|
|
Sex: Female, Male
Male
|
27 Participants
n=58 Participants
|
28 Participants
|
55 Participants
n=1 Participants
|
|
Race/Ethnicity, Customized
White
|
39 Participants
n=58 Participants
|
35 Participants
|
74 Participants
n=1 Participants
|
|
Race/Ethnicity, Customized
Black
|
2 Participants
n=58 Participants
|
4 Participants
|
6 Participants
n=1 Participants
|
|
Race/Ethnicity, Customized
Other
|
0 Participants
n=58 Participants
|
1 Participants
|
1 Participants
n=1 Participants
|
|
Neuropsychiatric Inventory-Irritability (NPI-I) -- Observer-rated
|
8.1 Scores on a scale
STANDARD_DEVIATION 2.6 • n=58 Participants
|
7.6 Scores on a scale
STANDARD_DEVIATION 2.6
|
7.9 Scores on a scale
STANDARD_DEVIATION 2.6 • n=1 Participants
|
|
Neuropsychiatric Inventory-Aggression (NPI-A) -- Observer-rated
|
6.7 Score
STANDARD_DEVIATION 3.5 • n=58 Participants
|
6.0 Score
STANDARD_DEVIATION 3.2
|
6.3 Score
STANDARD_DEVIATION 3.3 • n=1 Participants
|
|
TBI-Quality of Life -- Participant-rated
|
59.9 T-score
STANDARD_DEVIATION 7.3 • n=58 Participants
|
58.8 T-score
STANDARD_DEVIATION 9.1
|
59.4 T-score
STANDARD_DEVIATION 8.2 • n=1 Participants
|
|
Personal Health Questionnaire (PHQ)-9 - Participant-rated
|
9.8 Score
STANDARD_DEVIATION 5.6 • n=58 Participants
|
8.6 Score
STANDARD_DEVIATION 5.3
|
9.2 Score
STANDARD_DEVIATION 5.5 • n=1 Participants
|
|
General Anxiety Disorder (GAD-7) - Participant-rated
|
8.9 Score
STANDARD_DEVIATION 5.0 • n=58 Participants
|
8.7 Score
STANDARD_DEVIATION 6.3
|
8.8 Score
STANDARD_DEVIATION 5.7 • n=1 Participants
|
|
Neuropsychiatric Inventory-Irritability (NPI-I) -- Participant-rated
|
6.4 Scores on a scale
STANDARD_DEVIATION 3.2 • n=58 Participants
|
6.0 Scores on a scale
STANDARD_DEVIATION 3.6
|
6.2 Scores on a scale
STANDARD_DEVIATION 3.4 • n=1 Participants
|
|
Neuropsychiatric Inventory-Aggression (NPI-A) -- Participant-rated
|
5.5 Score
STANDARD_DEVIATION 3.6 • n=58 Participants
|
4.8 Score
STANDARD_DEVIATION 3.7
|
5.1 Score
STANDARD_DEVIATION 3.6 • n=1 Participants
|
PRIMARY outcome
Timeframe: Day 91Population: 3 participants withdrew
Neuropsychiatric Inventory (NPI) is a 40-item instrument evaluating 12 behavioral domains with prior use in TBI. NPI-Irritability domain (NPI-I) encompasses temper outbursts, mood fluctuations, abrupt anger, impatience, irritable disposition, and argumentative behavior. Assessment involves identifying if these behaviors are present and then scoring the most concerning manifestation on severity (1=mild to 3=severe) and frequency (1-4 scale, higher=greater occurrence). Domain totals (0-12 range) represent the product of severity and frequency ratings for the predominant symptom.
Outcome measures
| Measure |
Buspirone Treatment
n=38 Participants
starting at 15 mg/day and ending at 60 mg/day as prescribed
|
Buspirone Placebo
n=40 Participants
placebo tablets as prescribed
|
|---|---|---|
|
Neuropsychiatric Inventory-Irritability Domain - Observer-rated Proportion Improved ≥ 3 Points Baseline to Day-91
|
30 Participants
|
31 Participants
|
SECONDARY outcome
Timeframe: Day 91Population: 3 participants withdrew
Neuropsychiatric Inventory (NPI) is a 40-item instrument evaluating 12 behavioral domains with prior use in TBI. NPI-Aggression domain (NPI-A) captures emotional reactivity, resistance to activities, obstinate conduct, lack of cooperation, verbal outbursts, profanity, and physical aggression. Assessment involves identifying if these behaviors are present and then scoring the most concerning manifestation on severity (1=mild to 3=severe) and frequency (1-4 scale, higher=greater occurrence). Domain totals (0-12 range) represent the product of severity and frequency ratings for the predominant symptom.
Outcome measures
| Measure |
Buspirone Treatment
n=38 Participants
starting at 15 mg/day and ending at 60 mg/day as prescribed
|
Buspirone Placebo
n=40 Participants
placebo tablets as prescribed
|
|---|---|---|
|
Neuropsychiatric Inventory-Aggression Domain - Observer-rated Proportion Improved ≥ 3 Points Baseline to Day-91
|
28 Participants
|
27 Participants
|
SECONDARY outcome
Timeframe: Day 91Population: 3 participants withdrew
Neuropsychiatric Inventory (NPI) is a 40-item instrument evaluating 12 behavioral domains with prior use in TBI. NPI-Irritability domain (NPI-I) encompasses temper outbursts, mood fluctuations, abrupt anger, impatience, irritable disposition, and argumentative behavior. Assessment involves identifying if these behaviors are present and then scoring the most concerning manifestation on severity, frequency, and distress. The NPI-I Distress quantifies the emotional burden experienced by the rater regarding the most troublesome behavior using a 6-point rating system 0 to 5 (lower scores=lower distress).
Outcome measures
| Measure |
Buspirone Treatment
n=38 Participants
starting at 15 mg/day and ending at 60 mg/day as prescribed
|
Buspirone Placebo
n=40 Participants
placebo tablets as prescribed
|
|---|---|---|
|
Neuropsychiatric Inventory-Distress Irritability Domain - Observer-rated
|
2.0 Scores on a scale
Standard Error 0.2
|
1.7 Scores on a scale
Standard Error 0.2
|
SECONDARY outcome
Timeframe: Day 91Population: 3 participants withdrew
Neuropsychiatric Inventory (NPI) is a 40-item instrument evaluating 12 behavioral domains with prior use in TBI. NPI-Aggression domain (NPI-A) captures emotional reactivity, resistance to activities, obstinate conduct, lack of cooperation, verbal outbursts, profanity, and physical aggression. Assessment involves identifying if these behaviors are present and then scoring the most concerning manifestation on severity (1=mild to 3=severe) and frequency (1-4 scale, higher=greater occurrence). Domain totals (0-12 range) represent the product of severity and frequency ratings for the predominant symptom. The NPI-A Distress quantifies the emotional burden experienced by the rater regarding the most troublesome behavior using a 6-point rating system 0 - 5 (lower scores=lower distress).
Outcome measures
| Measure |
Buspirone Treatment
n=38 Participants
starting at 15 mg/day and ending at 60 mg/day as prescribed
|
Buspirone Placebo
n=40 Participants
placebo tablets as prescribed
|
|---|---|---|
|
Neuropsychiatric Inventory-Distress Aggression Domain - Observer Rated
|
1.5 Scores on a scale
Standard Error 0.2
|
1.3 Scores on a scale
Standard Error 0.2
|
SECONDARY outcome
Timeframe: Day 91Population: 3 participants withdrew
A self-report measure of overall neurobehavioral function. St Andrew's-Swansea Neurobehavioural Outcome Scale (SASNOS) is a 49-item observer-rated measure of neurobehavioral dysfunction in acquired brain injury. This study utilized the 15-item aggression subscale (overt aggression, irritability, and provocative behavior). The scale uses a 7-point Likert scale ("never" to "always") for items, and raw total scores are converted into standardized T-scores (M=50),(SD=10). Higher score reflects less aggression with a clinically relevant range usually extending from below (30) (indicating significant disability/high aggression) to (70) or higher (fewer symptoms).
Outcome measures
| Measure |
Buspirone Treatment
n=38 Participants
starting at 15 mg/day and ending at 60 mg/day as prescribed
|
Buspirone Placebo
n=40 Participants
placebo tablets as prescribed
|
|---|---|---|
|
St. Andrews-Swansea Neurobehavioural Outcome Scale - Observer-rated
|
51.7 units on a scale
Standard Error 1.3
|
53.1 units on a scale
Standard Error 1.2
|
SECONDARY outcome
Timeframe: Day 91Population: 3 participants withdrew
A self-report measure of overall change. Global Impression of Change (GIC) employs a 5-point Likert scale whereby observers rate perceived changes in the participant from significant improvement to substantial deterioration. High score reflects worsening. Score ranges 1 to 5: 1-much improved, 2-mildly improved, 3-unchanged, 4-mildly worsened, 5-much worsened.
Outcome measures
| Measure |
Buspirone Treatment
n=38 Participants
starting at 15 mg/day and ending at 60 mg/day as prescribed
|
Buspirone Placebo
n=40 Participants
placebo tablets as prescribed
|
|---|---|---|
|
Global Impressions of Change - Observer-rated
|
2.8 score on a scale
Standard Deviation 1.3
|
2.7 score on a scale
Standard Deviation 0.9
|
SECONDARY outcome
Timeframe: Day 91Population: 3 participants withdrew
A measure of depression that maps on to Diagnostic and Statistical Manual (DSM) criteria for depression. Personal Health Questionnaire-9 (PHQ-9) is a 9-item self-report depression screening based on DSM-V criteria with validity and reliability in TBI populations. Higher scores indicate greater presence of recent depression symptoms. PHQ-9 has a total score range of 0 to 27, based on 9 items scored from 0 ("not at all") to 3 ("nearly every day"). It is a validated tool for assessing depression severity in various populations, including those with traumatic brain injury.
Outcome measures
| Measure |
Buspirone Treatment
n=38 Participants
starting at 15 mg/day and ending at 60 mg/day as prescribed
|
Buspirone Placebo
n=40 Participants
placebo tablets as prescribed
|
|---|---|---|
|
Personal Health Questionnaire - Participant-rated
|
5.3 score on a scale
Standard Deviation 0.6
|
5.2 score on a scale
Standard Deviation 0.6
|
SECONDARY outcome
Timeframe: 91 dayPopulation: 3 participants withdrew
A self-report measure of anxiety. Generalized Anxiety Disorder-7 (GAD-7) is a 7-item self-report questionnaire assessing generalized anxiety disorder symptoms based on DSM-V criteria. Total score ranges from 0 to 21, where higher scores indicate greater severity of anxiety. Scores are categorized as: 0-4 (Minimal), 5-9 (Mild), 10-14 (Moderate), and 15-21 (Severe). A score of 10 or higher is commonly used as the cutoff for clinical screening.
Outcome measures
| Measure |
Buspirone Treatment
n=38 Participants
starting at 15 mg/day and ending at 60 mg/day as prescribed
|
Buspirone Placebo
n=40 Participants
placebo tablets as prescribed
|
|---|---|---|
|
Generalized Anxiety Disorder - Participant-rated
|
6.0 score on a scale
Standard Error 0.7
|
4.8 score on a scale
Standard Error 0.7
|
SECONDARY outcome
Timeframe: Day 91Population: 3 participants withdrew
A self-report measure of overall impact of anger on quality of life. TBI-Quality of Life (TBI-QOL) Anger is a 10-item measure of the continuum of anger in TBI populations that is calibrated with the Patient Reporter Outcome Measurement Information System (PROMIS) scales. The measure assesses self-reported frequency and intensity of anger symptoms-including irritability, frustration, and outward aggression-in individuals with traumatic brain injuries. A T-score metric is used, typically ranging from roughly 30 to 80+, where a mean of 50 and a standard deviation (SD) of 10 represent the general population. Higher scores indicate more severe anger.
Outcome measures
| Measure |
Buspirone Treatment
n=38 Participants
starting at 15 mg/day and ending at 60 mg/day as prescribed
|
Buspirone Placebo
n=40 Participants
placebo tablets as prescribed
|
|---|---|---|
|
Traumatic Brain Injury-Quality of Life Anger - Participant-rated
|
50.8 T-score
Standard Error 1.4
|
51.0 T-score
Standard Error 1.4
|
SECONDARY outcome
Timeframe: Day 91Population: 3 participants withdrew
Clinician rating of overall change. The Clinical Global Impressions (CGI) scale is a 3-item, 7-point observer-rated instrument used in psychiatry to assess treatment response. It measures severity of illness (1-7), global improvement (1-7), and the efficacy index (0-4) or specific combinations of therapeutic/side effects). Lower scores generally indicate better outcomes (e.g., 1="Very much improved"). CGI-Improvement (CGI-I) (1-7): Assesses change from baseline, with 1 indicating "very much improved" and 7 indicating "very much worse".
Outcome measures
| Measure |
Buspirone Treatment
n=38 Participants
starting at 15 mg/day and ending at 60 mg/day as prescribed
|
Buspirone Placebo
n=40 Participants
placebo tablets as prescribed
|
|---|---|---|
|
Clinical Global Impressions -- Global Improvement -- Clinician Rated.
|
2.4 score on a scale
Standard Deviation 1.4
|
2.1 score on a scale
Standard Deviation 1.1
|
Adverse Events
Buspirone Treatment
Buspirone Placebo
Serious adverse events
| Measure |
Buspirone Treatment
n=41 participants at risk
starting at 15 mg/day and ending at 60 mg/day as prescribed
|
Buspirone Placebo
n=40 participants at risk
placebo tablets as prescribed
|
|---|---|---|
|
Nervous system disorders
Seizure
|
0.00%
0/41 • From enrollment until end of day 91 follow up visit
|
2.5%
1/40 • Number of events 1 • From enrollment until end of day 91 follow up visit
|
Other adverse events
| Measure |
Buspirone Treatment
n=41 participants at risk
starting at 15 mg/day and ending at 60 mg/day as prescribed
|
Buspirone Placebo
n=40 participants at risk
placebo tablets as prescribed
|
|---|---|---|
|
Ear and labyrinth disorders
Ear and labyrinth disorders
|
2.4%
1/41 • From enrollment until end of day 91 follow up visit
|
2.5%
1/40 • From enrollment until end of day 91 follow up visit
|
|
Eye disorders
Eye disorders
|
2.4%
1/41 • From enrollment until end of day 91 follow up visit
|
0.00%
0/40 • From enrollment until end of day 91 follow up visit
|
|
Gastrointestinal disorders
Gastrointestinal disorders
|
12.2%
5/41 • From enrollment until end of day 91 follow up visit
|
15.0%
6/40 • From enrollment until end of day 91 follow up visit
|
|
General disorders
General disorders and administration conditions
|
9.8%
4/41 • From enrollment until end of day 91 follow up visit
|
17.5%
7/40 • From enrollment until end of day 91 follow up visit
|
|
Immune system disorders
Immune system disorders
|
0.00%
0/41 • From enrollment until end of day 91 follow up visit
|
2.5%
1/40 • From enrollment until end of day 91 follow up visit
|
|
Infections and infestations
Infections
|
2.4%
1/41 • From enrollment until end of day 91 follow up visit
|
12.5%
5/40 • From enrollment until end of day 91 follow up visit
|
|
Injury, poisoning and procedural complications
Injury, poisoning, and procedures complications
|
0.00%
0/41 • From enrollment until end of day 91 follow up visit
|
5.0%
2/40 • From enrollment until end of day 91 follow up visit
|
|
Musculoskeletal and connective tissue disorders
Musculoskeletal
|
0.00%
0/41 • From enrollment until end of day 91 follow up visit
|
2.5%
1/40 • From enrollment until end of day 91 follow up visit
|
|
Nervous system disorders
Neurologic
|
19.5%
8/41 • From enrollment until end of day 91 follow up visit
|
15.0%
6/40 • From enrollment until end of day 91 follow up visit
|
|
Psychiatric disorders
Psychiatric
|
14.6%
6/41 • From enrollment until end of day 91 follow up visit
|
25.0%
10/40 • From enrollment until end of day 91 follow up visit
|
|
Renal and urinary disorders
Urinary Tract
|
2.4%
1/41 • From enrollment until end of day 91 follow up visit
|
0.00%
0/40 • From enrollment until end of day 91 follow up visit
|
|
Respiratory, thoracic and mediastinal disorders
Pulmonary
|
2.4%
1/41 • From enrollment until end of day 91 follow up visit
|
12.5%
5/40 • From enrollment until end of day 91 follow up visit
|
|
Skin and subcutaneous tissue disorders
Dermatologic
|
4.9%
2/41 • From enrollment until end of day 91 follow up visit
|
2.5%
1/40 • From enrollment until end of day 91 follow up visit
|
|
Vascular disorders
Vascular
|
2.4%
1/41 • From enrollment until end of day 91 follow up visit
|
0.00%
0/40 • From enrollment until end of day 91 follow up visit
|
Additional Information
Results disclosure agreements
- Principal investigator is a sponsor employee
- Publication restrictions are in place