Trial Outcomes & Findings for Gabapentin for Bipolar & Cannabis Use Disorders (NCT NCT03334721)

NCT ID: NCT03334721

Last Updated: 2020-11-13

Results Overview

Concentrations of GABA, normalized to water and corrected for CSF%, in dorsal anterior cingulate measured via Proton Magnetic Resonance Spectroscopy.

Recruitment status

COMPLETED

Study phase

PHASE2

Target enrollment

23 participants

Primary outcome timeframe

Day 5 of each experimental condition

Results posted on

2020-11-13

Participant Flow

Participant milestones

Participant milestones
Measure
Gabapentin, Then Placebo Oral Capsule
Week 1: 1-week condition will consist of an in-person study visit for assessment and dispensing of medication (Day 1), titration to maximum dose (i.e., 1,200mg gabapentin) (Days 1-5), MRI (Day 5), and medication washout (Days 5-7). Week 2: 1-week condition will consist of an in-person study visit for assessment and dispensing of medication (Day 1), titration to maximum dose (Days 1-5), MRI (Day 5), and medication washout (Days 5-7). Gabapentin: 5 day trial of gabapentin with titration to 1,200mg Placebo Oral Capsule: 5 day trial of matched placebo
Placebo Oral Capsule, Then Gabapentin
Week 1: 1-week condition will consist of an in-person study visit for assessment and dispensing of medication (Day 1), titration to maximum dose (Days 1-5), MRI (Day 5), and medication washout (Days 5-7). Week 2: 1-week condition will consist of an in-person study visit for assessment and dispensing of Gabapentin medication (Day 1), titration to maximum dose (i.e., 1,200mg gabapentin) (days 1-5), MRI (Day 5), and medication washout (Days 5-7). Gabapentin: 5 day trial of gabapentin with titration to 1,200mg Placebo Oral Capsule: 5 day trial of matched placebo
Overall Study
STARTED
12
11
Overall Study
COMPLETED
10
11
Overall Study
NOT COMPLETED
2
0

Reasons for withdrawal

Reasons for withdrawal
Measure
Gabapentin, Then Placebo Oral Capsule
Week 1: 1-week condition will consist of an in-person study visit for assessment and dispensing of medication (Day 1), titration to maximum dose (i.e., 1,200mg gabapentin) (Days 1-5), MRI (Day 5), and medication washout (Days 5-7). Week 2: 1-week condition will consist of an in-person study visit for assessment and dispensing of medication (Day 1), titration to maximum dose (Days 1-5), MRI (Day 5), and medication washout (Days 5-7). Gabapentin: 5 day trial of gabapentin with titration to 1,200mg Placebo Oral Capsule: 5 day trial of matched placebo
Placebo Oral Capsule, Then Gabapentin
Week 1: 1-week condition will consist of an in-person study visit for assessment and dispensing of medication (Day 1), titration to maximum dose (Days 1-5), MRI (Day 5), and medication washout (Days 5-7). Week 2: 1-week condition will consist of an in-person study visit for assessment and dispensing of Gabapentin medication (Day 1), titration to maximum dose (i.e., 1,200mg gabapentin) (days 1-5), MRI (Day 5), and medication washout (Days 5-7). Gabapentin: 5 day trial of gabapentin with titration to 1,200mg Placebo Oral Capsule: 5 day trial of matched placebo
Overall Study
Withdrawal by Subject
1
0
Overall Study
No longer met inclusion/exclusion criter
1
0

Baseline Characteristics

Gabapentin for Bipolar & Cannabis Use Disorders

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure
Gabapentin, Then Placebo Oral Capsule
n=12 Participants
Week 1: Gabapentin: 1-week condition will consist of an in-person study visit for assessment and dispensing of medication (Day 1), titration to maximum dose (i.e., 1,200mg gabapentin) (Days 1-5), MRI (Day 5), and medication washout (Days 5-7). Week 2: Placebo: 1-week condition will consist of an in-person study visit for assessment and dispensing of medication (Day 1), titration to maximum dose (Days 1-5), MRI (Day 5), and medication washout (Days 5-7).
Placebo Oral Capsule, Then Gabapentin
n=11 Participants
Week 1: Placebo: 1-week condition will consist of an in-person study visit for assessment and dispensing of medication (Day 1), titration to maximum dose (Days 1-5), MRI (Day 5), and medication washout (Days 5-7). Week 2: Gabapentin: 1-week condition will consist of an in-person study visit for assessment and dispensing of medication (Day 1), titration to maximum dose (i.e., 1,200mg gabapentin) (Days 1-5), MRI (Day 5), and medication washout (Days 5-7).
Total
n=23 Participants
Total of all reporting groups
Age, Categorical
<=18 years
0 Participants
n=5 Participants
1 Participants
n=7 Participants
1 Participants
n=5 Participants
Age, Categorical
Between 18 and 65 years
12 Participants
n=5 Participants
10 Participants
n=7 Participants
22 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
38.58 years
n=5 Participants
35.45 years
n=7 Participants
37.09 years
n=5 Participants
Sex: Female, Male
Female
6 Participants
n=5 Participants
5 Participants
n=7 Participants
11 Participants
n=5 Participants
Sex: Female, Male
Male
6 Participants
n=5 Participants
6 Participants
n=7 Participants
12 Participants
n=5 Participants
Ethnicity (NIH/OMB)
Hispanic or Latino
0 Participants
n=5 Participants
0 Participants
n=7 Participants
0 Participants
n=5 Participants
Ethnicity (NIH/OMB)
Not Hispanic or Latino
12 Participants
n=5 Participants
11 Participants
n=7 Participants
23 Participants
n=5 Participants
Ethnicity (NIH/OMB)
Unknown or Not Reported
0 Participants
n=5 Participants
0 Participants
n=7 Participants
0 Participants
n=5 Participants
Race (NIH/OMB)
American Indian or Alaska Native
0 Participants
n=5 Participants
0 Participants
n=7 Participants
0 Participants
n=5 Participants
Race (NIH/OMB)
Asian
1 Participants
n=5 Participants
0 Participants
n=7 Participants
1 Participants
n=5 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
0 Participants
n=5 Participants
0 Participants
n=7 Participants
0 Participants
n=5 Participants
Race (NIH/OMB)
Black or African American
2 Participants
n=5 Participants
4 Participants
n=7 Participants
6 Participants
n=5 Participants
Race (NIH/OMB)
White
9 Participants
n=5 Participants
7 Participants
n=7 Participants
16 Participants
n=5 Participants
Race (NIH/OMB)
More than one race
0 Participants
n=5 Participants
0 Participants
n=7 Participants
0 Participants
n=5 Participants
Race (NIH/OMB)
Unknown or Not Reported
0 Participants
n=5 Participants
0 Participants
n=7 Participants
0 Participants
n=5 Participants
Region of Enrollment
United States
12 Participants
n=5 Participants
11 Participants
n=7 Participants
23 Participants
n=5 Participants

PRIMARY outcome

Timeframe: Day 5 of each experimental condition

Population: Individuals with Bipolar Disorder and Cannabis Use Disorder

Concentrations of GABA, normalized to water and corrected for CSF%, in dorsal anterior cingulate measured via Proton Magnetic Resonance Spectroscopy.

Outcome measures

Outcome measures
Measure
Gabapentin
n=22 Participants
Each 1-week condition will consist of an in-person study visit for assessment and dispensing of medication (Day 1), titration to maximum dose (i.e., 1,200mg gabapentin) (Days 1-5), MRI (Day 5), and medication washout (Days 5-7). Gabapentin: 5 day trial of gabapentin with titration to 1,200mg
Placebo Oral Capsule
n=21 Participants
Each 1-week condition will consist of an in-person study visit for assessment and dispensing of medication (Day 1), titration to maximum dose (Days 1-5), MRI (Day 5), and medication washout (Days 5-7). Placebo Oral Capsule: 5 day trial of matched placebo
Prefrontal GABA Concentrations Through Proton Magnetic Resonance Spectroscopy
GABA (randomization order 1, gabapentin 1st)
2.625 Institutional Units
Standard Deviation 0.324
2.696 Institutional Units
Standard Deviation 0.313
Prefrontal GABA Concentrations Through Proton Magnetic Resonance Spectroscopy
GABA (randomization order 2, placebo 1st)
2.609 Institutional Units
Standard Deviation 0.290
2.720 Institutional Units
Standard Deviation 0.248

Adverse Events

Gabapentin

Serious events: 0 serious events
Other events: 8 other events
Deaths: 0 deaths

Placebo Oral Capsule

Serious events: 0 serious events
Other events: 6 other events
Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Other adverse events
Measure
Gabapentin
n=23 participants at risk
Each 1-week condition will consist of an in-person study visit for assessment and dispensing of medication (Day 1), titration to maximum dose (i.e., 1,200mg gabapentin) (Days 1-5), MRI (Day 5), and medication washout (Days 5-7). Gabapentin: 5 day trial of gabapentin with titration to 1,200mg
Placebo Oral Capsule
n=22 participants at risk
Each 1-week condition will consist of an in-person study visit for assessment and dispensing of medication (Day 1), titration to maximum dose (Days 1-5), MRI (Day 5), and medication washout (Days 5-7). Placebo Oral Capsule: 5 day trial of matched placebo
Gastrointestinal disorders
Nausea
4.3%
1/23 • Number of events 1 • Adverse events were collected over a total of 4 visits (Med 1, MRI 1, Med 2, MRI 2) for each participant; 2-weeks.
Please note -23 participants took gabapentin but only 22 took placebo because one participant dropped out of the study prior to receiving the placebo oral capsule (this was a crossover study).
4.5%
1/22 • Number of events 1 • Adverse events were collected over a total of 4 visits (Med 1, MRI 1, Med 2, MRI 2) for each participant; 2-weeks.
Please note -23 participants took gabapentin but only 22 took placebo because one participant dropped out of the study prior to receiving the placebo oral capsule (this was a crossover study).
Gastrointestinal disorders
Vomiting
4.3%
1/23 • Number of events 1 • Adverse events were collected over a total of 4 visits (Med 1, MRI 1, Med 2, MRI 2) for each participant; 2-weeks.
Please note -23 participants took gabapentin but only 22 took placebo because one participant dropped out of the study prior to receiving the placebo oral capsule (this was a crossover study).
0.00%
0/22 • Adverse events were collected over a total of 4 visits (Med 1, MRI 1, Med 2, MRI 2) for each participant; 2-weeks.
Please note -23 participants took gabapentin but only 22 took placebo because one participant dropped out of the study prior to receiving the placebo oral capsule (this was a crossover study).
Gastrointestinal disorders
Diarrhea
0.00%
0/23 • Adverse events were collected over a total of 4 visits (Med 1, MRI 1, Med 2, MRI 2) for each participant; 2-weeks.
Please note -23 participants took gabapentin but only 22 took placebo because one participant dropped out of the study prior to receiving the placebo oral capsule (this was a crossover study).
4.5%
1/22 • Number of events 1 • Adverse events were collected over a total of 4 visits (Med 1, MRI 1, Med 2, MRI 2) for each participant; 2-weeks.
Please note -23 participants took gabapentin but only 22 took placebo because one participant dropped out of the study prior to receiving the placebo oral capsule (this was a crossover study).
General disorders
Fatigue
17.4%
4/23 • Number of events 4 • Adverse events were collected over a total of 4 visits (Med 1, MRI 1, Med 2, MRI 2) for each participant; 2-weeks.
Please note -23 participants took gabapentin but only 22 took placebo because one participant dropped out of the study prior to receiving the placebo oral capsule (this was a crossover study).
0.00%
0/22 • Adverse events were collected over a total of 4 visits (Med 1, MRI 1, Med 2, MRI 2) for each participant; 2-weeks.
Please note -23 participants took gabapentin but only 22 took placebo because one participant dropped out of the study prior to receiving the placebo oral capsule (this was a crossover study).
Nervous system disorders
Dizziness
8.7%
2/23 • Number of events 2 • Adverse events were collected over a total of 4 visits (Med 1, MRI 1, Med 2, MRI 2) for each participant; 2-weeks.
Please note -23 participants took gabapentin but only 22 took placebo because one participant dropped out of the study prior to receiving the placebo oral capsule (this was a crossover study).
0.00%
0/22 • Adverse events were collected over a total of 4 visits (Med 1, MRI 1, Med 2, MRI 2) for each participant; 2-weeks.
Please note -23 participants took gabapentin but only 22 took placebo because one participant dropped out of the study prior to receiving the placebo oral capsule (this was a crossover study).
Eye disorders
Blepharospasm
4.3%
1/23 • Number of events 1 • Adverse events were collected over a total of 4 visits (Med 1, MRI 1, Med 2, MRI 2) for each participant; 2-weeks.
Please note -23 participants took gabapentin but only 22 took placebo because one participant dropped out of the study prior to receiving the placebo oral capsule (this was a crossover study).
0.00%
0/22 • Adverse events were collected over a total of 4 visits (Med 1, MRI 1, Med 2, MRI 2) for each participant; 2-weeks.
Please note -23 participants took gabapentin but only 22 took placebo because one participant dropped out of the study prior to receiving the placebo oral capsule (this was a crossover study).
Nervous system disorders
Headache
4.3%
1/23 • Number of events 1 • Adverse events were collected over a total of 4 visits (Med 1, MRI 1, Med 2, MRI 2) for each participant; 2-weeks.
Please note -23 participants took gabapentin but only 22 took placebo because one participant dropped out of the study prior to receiving the placebo oral capsule (this was a crossover study).
9.1%
2/22 • Number of events 2 • Adverse events were collected over a total of 4 visits (Med 1, MRI 1, Med 2, MRI 2) for each participant; 2-weeks.
Please note -23 participants took gabapentin but only 22 took placebo because one participant dropped out of the study prior to receiving the placebo oral capsule (this was a crossover study).
Metabolism and nutrition disorders
Increased Appetite
4.3%
1/23 • Number of events 1 • Adverse events were collected over a total of 4 visits (Med 1, MRI 1, Med 2, MRI 2) for each participant; 2-weeks.
Please note -23 participants took gabapentin but only 22 took placebo because one participant dropped out of the study prior to receiving the placebo oral capsule (this was a crossover study).
4.5%
1/22 • Number of events 1 • Adverse events were collected over a total of 4 visits (Med 1, MRI 1, Med 2, MRI 2) for each participant; 2-weeks.
Please note -23 participants took gabapentin but only 22 took placebo because one participant dropped out of the study prior to receiving the placebo oral capsule (this was a crossover study).
Nervous system disorders
Somnolence
4.3%
1/23 • Number of events 1 • Adverse events were collected over a total of 4 visits (Med 1, MRI 1, Med 2, MRI 2) for each participant; 2-weeks.
Please note -23 participants took gabapentin but only 22 took placebo because one participant dropped out of the study prior to receiving the placebo oral capsule (this was a crossover study).
0.00%
0/22 • Adverse events were collected over a total of 4 visits (Med 1, MRI 1, Med 2, MRI 2) for each participant; 2-weeks.
Please note -23 participants took gabapentin but only 22 took placebo because one participant dropped out of the study prior to receiving the placebo oral capsule (this was a crossover study).
Nervous system disorders
Memory Impairment
4.3%
1/23 • Number of events 1 • Adverse events were collected over a total of 4 visits (Med 1, MRI 1, Med 2, MRI 2) for each participant; 2-weeks.
Please note -23 participants took gabapentin but only 22 took placebo because one participant dropped out of the study prior to receiving the placebo oral capsule (this was a crossover study).
4.5%
1/22 • Number of events 1 • Adverse events were collected over a total of 4 visits (Med 1, MRI 1, Med 2, MRI 2) for each participant; 2-weeks.
Please note -23 participants took gabapentin but only 22 took placebo because one participant dropped out of the study prior to receiving the placebo oral capsule (this was a crossover study).
Musculoskeletal and connective tissue disorders
Abdominal Pain
0.00%
0/23 • Adverse events were collected over a total of 4 visits (Med 1, MRI 1, Med 2, MRI 2) for each participant; 2-weeks.
Please note -23 participants took gabapentin but only 22 took placebo because one participant dropped out of the study prior to receiving the placebo oral capsule (this was a crossover study).
4.5%
1/22 • Number of events 1 • Adverse events were collected over a total of 4 visits (Med 1, MRI 1, Med 2, MRI 2) for each participant; 2-weeks.
Please note -23 participants took gabapentin but only 22 took placebo because one participant dropped out of the study prior to receiving the placebo oral capsule (this was a crossover study).
Psychiatric disorders
Insomnia
4.3%
1/23 • Number of events 1 • Adverse events were collected over a total of 4 visits (Med 1, MRI 1, Med 2, MRI 2) for each participant; 2-weeks.
Please note -23 participants took gabapentin but only 22 took placebo because one participant dropped out of the study prior to receiving the placebo oral capsule (this was a crossover study).
0.00%
0/22 • Adverse events were collected over a total of 4 visits (Med 1, MRI 1, Med 2, MRI 2) for each participant; 2-weeks.
Please note -23 participants took gabapentin but only 22 took placebo because one participant dropped out of the study prior to receiving the placebo oral capsule (this was a crossover study).

Additional Information

James J. Prisciandaro, Ph.D.

Medical University of South Carolina

Phone: 843-792-1433

Results disclosure agreements

  • Principal investigator is a sponsor employee
  • Publication restrictions are in place