Trial Outcomes & Findings for A Trial of the Fatty Acid Amide Hydrolase Inhibitor Palmitoylethanolamide in Bipolar Depression (NCT NCT06229977)

NCT ID: NCT06229977

Last Updated: 2026-08-13

Results Overview

The Hamilton Depression Rating Scale measures severity of depression. The total score ranges from 0 to 26, higher score indicating greater depression severity. The change in score will be reported. The change in score will be reported as the \[(Score at 6 weeks follow up) - (Score at Baseline)\] - A negative value indicates improvement of depression severity.

Recruitment status

COMPLETED

Study phase

PHASE2

Target enrollment

34 participants

Primary outcome timeframe

Baseline, 6 weeks follow up

Results posted on

2026-08-13

Participant Flow

Participant milestones

Participant milestones
Measure
PEA Plus Treatment as Usual (TAU)
Palmitoylethanolamide administered orally in addition to participants' existing mood stabilizer/antipsychotic/antidepressant regimen
Placebo Plus Treatment as Usual (TAU)
Matching placebo administered orally in addition to participants' existing mood stabilizer/antipsychotic/antidepressant regimen
Overall Study
STARTED
18
16
Overall Study
COMPLETED
16
12
Overall Study
NOT COMPLETED
2
4

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

A Trial of the Fatty Acid Amide Hydrolase Inhibitor Palmitoylethanolamide in Bipolar Depression

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure
PEA Plus Treatment as Usual (TAU)
n=18 Participants
Palmitoylethanolamide administered orally in addition to participants' existing mood stabilizer/antipsychotic/antidepressant regimen
Placebo Plus Treatment as Usual (TAU)
n=16 Participants
Matching placebo administered orally in addition to participants' existing mood stabilizer/antipsychotic/antidepressant regimen
Total
n=34 Participants
Total of all reporting groups
Age, Categorical
<=18 years
0 Participants
n=1 Participants
0 Participants
n=1 Participants
0 Participants
n=1 Participants
Age, Categorical
Between 18 and 65 years
16 Participants
n=1 Participants
16 Participants
n=1 Participants
32 Participants
n=1 Participants
Age, Categorical
>=65 years
2 Participants
n=1 Participants
0 Participants
n=1 Participants
2 Participants
n=1 Participants
Sex: Female, Male
Female
12 Participants
n=1 Participants
13 Participants
n=1 Participants
25 Participants
n=1 Participants
Sex: Female, Male
Male
6 Participants
n=1 Participants
3 Participants
n=1 Participants
9 Participants
n=1 Participants
Race (NIH/OMB)
American Indian or Alaska Native
0 Participants
n=1 Participants
0 Participants
n=1 Participants
0 Participants
n=1 Participants
Race (NIH/OMB)
Asian
0 Participants
n=1 Participants
1 Participants
n=1 Participants
1 Participants
n=1 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
0 Participants
n=1 Participants
0 Participants
n=1 Participants
0 Participants
n=1 Participants
Race (NIH/OMB)
Black or African American
4 Participants
n=1 Participants
4 Participants
n=1 Participants
8 Participants
n=1 Participants
Race (NIH/OMB)
White
14 Participants
n=1 Participants
11 Participants
n=1 Participants
25 Participants
n=1 Participants
Race (NIH/OMB)
More than one race
0 Participants
n=1 Participants
0 Participants
n=1 Participants
0 Participants
n=1 Participants
Race (NIH/OMB)
Unknown or Not Reported
0 Participants
n=1 Participants
0 Participants
n=1 Participants
0 Participants
n=1 Participants
Region of Enrollment
United States
18 Participants
n=1 Participants
16 Participants
n=1 Participants
34 Participants
n=1 Participants
Montgomery Äsberg Depression Rating Scale Score
29 score on a scale
STANDARD_DEVIATION 2 • n=1 Participants
28 score on a scale
STANDARD_DEVIATION 2 • n=1 Participants
28 score on a scale
STANDARD_DEVIATION 1 • n=1 Participants
Hamilton Depression Rating Scale Score
21 score on a scale
STANDARD_DEVIATION 1 • n=1 Participants
21 score on a scale
STANDARD_DEVIATION 1 • n=1 Participants
21 score on a scale
STANDARD_DEVIATION 1 • n=1 Participants
Columbia Suicide Severity Rating Scale (C-SSRS) Risk Score
1 score on a scale
STANDARD_DEVIATION 0 • n=1 Participants
1 score on a scale
STANDARD_DEVIATION 0 • n=1 Participants
1 score on a scale
STANDARD_DEVIATION 0 • n=1 Participants

PRIMARY outcome

Timeframe: Baseline, 6 weeks follow up

Population: Analysis includes participants with both a baseline and a Visit 4 (Week 6) Hamilton Depression Rating Scale (HAM-D) score available. 2 participants from the PEA plus Treatment as Usual (TAU) arm and 4 participants from the Placebo plus Treatment as Usual (TAU) arm discontinued the study prior to Visit 4 or had a missing Visit 4 assessment and were excluded.

The Hamilton Depression Rating Scale measures severity of depression. The total score ranges from 0 to 26, higher score indicating greater depression severity. The change in score will be reported. The change in score will be reported as the \[(Score at 6 weeks follow up) - (Score at Baseline)\] - A negative value indicates improvement of depression severity.

Outcome measures

Outcome measures
Measure
PEA Plus Treatment as Usual (TAU)
n=16 Participants
Palmitoylethanolamide administered orally in addition to participants' existing mood stabilizer/antipsychotic/antidepressant regimen
Placebo Plus Treatment as Usual (TAU)
n=12 Participants
Matching placebo administered orally in addition to participants' existing mood stabilizer/antipsychotic/antidepressant regimen
Change in Depression as Assessed by the Hamilton Depression Rating Scale (HAM-D)
-12.38 score on a scale
Interval -15.93 to -8.83
-13.03 score on a scale
Interval -16.78 to -9.28

SECONDARY outcome

Timeframe: from baseline to end of study (6 week follow up)

Population: Analysis includes participants with both a baseline and a Visit 4 (Week 6) Hamilton Depression Rating Scale (HAM-D) score available. 2 participants from the PEA plus Treatment as Usual (TAU) arm and 4 participants from the Placebo plus Treatment as Usual (TAU) arm discontinued the study prior to Visit 4 or had a missing Visit 4 assessment and were excluded.

Remission of depressive symptoms is defined by a HAM-D score of ≤7. The Hamilton Depression Rating Scale (HAM-D) measures severity of depression. The total score ranges from 0 to 26, higher score indicating greater depression severity

Outcome measures

Outcome measures
Measure
PEA Plus Treatment as Usual (TAU)
n=16 Participants
Palmitoylethanolamide administered orally in addition to participants' existing mood stabilizer/antipsychotic/antidepressant regimen
Placebo Plus Treatment as Usual (TAU)
n=12 Participants
Matching placebo administered orally in addition to participants' existing mood stabilizer/antipsychotic/antidepressant regimen
Number of Participants That Show a Remission of Depressive Symptoms as Assessed by the HAM-D Scale
7 Participants
7 Participants

SECONDARY outcome

Timeframe: from baseline to end of study (6 week follow up)

Population: Analysis includes participants with both a baseline and a Visit 4 (Week 6) Hamilton Depression Rating Scale (HAM-D) score available. 2 participants from the PEA plus Treatment as Usual (TAU) arm and 4 participants from the Placebo plus Treatment as Usual (TAU) arm discontinued the study prior to Visit 4 or had a missing Visit 4 assessment and were excluded.

Response rate is defined by ≥ 50 % reduction in HAM-D Score from baseline. The Hamilton Depression Rating Scale (HAM-D) measures severity of depression. The total score ranges from 0 to 26, higher score indicating greater depression severity

Outcome measures

Outcome measures
Measure
PEA Plus Treatment as Usual (TAU)
n=16 Participants
Palmitoylethanolamide administered orally in addition to participants' existing mood stabilizer/antipsychotic/antidepressant regimen
Placebo Plus Treatment as Usual (TAU)
n=12 Participants
Matching placebo administered orally in addition to participants' existing mood stabilizer/antipsychotic/antidepressant regimen
Number of Participants That Show a Response as Assessed by the HAM-D Scale
9 Participants
9 Participants

SECONDARY outcome

Timeframe: Baseline, 6 weeks follow up

Population: Analysis includes participants with both a baseline and a Visit 4 (Week 6) Montgomery-Åsberg Depression Rating Scale (MADRS) score available. 3 participants from the PEA plus Treatment as Usual (TAU) arm and 4 participants from the Placebo plus Treatment as Usual (TAU) arm discontinued the study prior to Visit 4 or had a missing Visit 4 assessment and were excluded.

The Montgomery Äsberg Depression Rating Scale measures severity in depression. The total score ranges from 0 to 60, a higher score indicating greater depression. The change in score will be reported. The change in score will be reported as the \[(Score at 6 weeks follow up) - (Score at Baseline)\] - A negative value indicates improvement of depression severity.

Outcome measures

Outcome measures
Measure
PEA Plus Treatment as Usual (TAU)
n=15 Participants
Palmitoylethanolamide administered orally in addition to participants' existing mood stabilizer/antipsychotic/antidepressant regimen
Placebo Plus Treatment as Usual (TAU)
n=12 Participants
Matching placebo administered orally in addition to participants' existing mood stabilizer/antipsychotic/antidepressant regimen
Change in Depression as Assessed by the Montgomery Äsberg Depression Rating Scale (MADRS)
-15.97 score on a scale
Interval -22.48 to -9.46
-18.22 score on a scale
Interval -25.14 to -11.3

SECONDARY outcome

Timeframe: Baseline To Week 6

Population: Analysis includes all randomized participants in each arm who had at least one post-baseline HAM-D assessment available.

Time to first study visit at which a participant achieved ≥50% reduction from baseline HAM-D total score. The Hamilton Depression Rating Scale (HAM-D) measures severity of depression. The total score ranges from 0 to 26, higher score indicating greater depression severity

Outcome measures

Outcome measures
Measure
PEA Plus Treatment as Usual (TAU)
n=17 Participants
Palmitoylethanolamide administered orally in addition to participants' existing mood stabilizer/antipsychotic/antidepressant regimen
Placebo Plus Treatment as Usual (TAU)
n=14 Participants
Matching placebo administered orally in addition to participants' existing mood stabilizer/antipsychotic/antidepressant regimen
Time to Response - HAM-D (≥50% Reduction From Baseline)
4 Weeks
Interval 2.0 to 6.0
2 Weeks
Interval 2.0 to 4.0

Adverse Events

PEA Plus Treatment as Usual (TAU)

Serious events: 0 serious events
Other events: 3 other events
Deaths: 0 deaths

Placebo Plus Treatment as Usual (TAU)

Serious events: 0 serious events
Other events: 3 other events
Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Other adverse events
Measure
PEA Plus Treatment as Usual (TAU)
n=18 participants at risk
Palmitoylethanolamide administered orally in addition to participants' existing mood stabilizer/antipsychotic/antidepressant regimen
Placebo Plus Treatment as Usual (TAU)
n=16 participants at risk
Matching placebo administered orally in addition to participants' existing mood stabilizer/antipsychotic/antidepressant regimen
Nervous system disorders
Headache
5.6%
1/18 • Number of events 2 • 6 weeks
6.2%
1/16 • Number of events 2 • 6 weeks
Nervous system disorders
Vertigo
5.6%
1/18 • Number of events 1 • 6 weeks
0.00%
0/16 • 6 weeks
Immune system disorders
Dry Mouth
5.6%
1/18 • Number of events 1 • 6 weeks
6.2%
1/16 • Number of events 1 • 6 weeks
Musculoskeletal and connective tissue disorders
Arthralgia (Aching Joints)
5.6%
1/18 • Number of events 1 • 6 weeks
0.00%
0/16 • 6 weeks
Endocrine disorders
Decreased Appetite
5.6%
1/18 • Number of events 1 • 6 weeks
0.00%
0/16 • 6 weeks
Skin and subcutaneous tissue disorders
Skin Rash
0.00%
0/18 • 6 weeks
6.2%
1/16 • Number of events 1 • 6 weeks

Additional Information

Dr. Rodrigo Machado-Vieira

The University of Texas Health Science Center at Houston

Phone: 713-500-1832

Results disclosure agreements

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