Trial Outcomes & Findings for Irritable Bowel Syndrome (IBS) Functional Magnetic Resonance Imaging (fMRI) With Desipramine (NCT NCT00880594)

Last Updated: 2026-01-22

Results Overview

CONTRASTS (comparisons of study group BOLD activations vs rest) are the outcome of interest. Voxel-wise comparisons (ANOVAs) were performed to determine differences in activations between groups within these regions. First level analyses of rectal balloon distensions experienced by subjects were modeled as box car functions then convolved with the canonical hemodynamic response function (HRF). For the second level analyses, differences in brain activation while experiencing both high and low painful rectal balloon distensions between IBS patients with High somatization vs Low somatization were examined with two-sample t-tests utilizing contrast images generated from the first level analysis. Unconventionally, these inferential statistics are regarded as the primary outcome in the study. Accordingly individual group level BOLD values where not recorded or evaluated separately in the cohorts. These data are not available, and cannot be reported "per Arm".

Recruitment status

TERMINATED

Study phase

Target enrollment

18 participants

Primary outcome timeframe

1 month

Results posted on

2026-01-22

Participant Flow

Participant milestones

Participant milestones
Measure	IBS-High Somatization (Open Label Desipramine) IBS patients with high somatization (IBS-S+, ) IBS defined by Rome III, somatization by high PHQ-15. Desipramine: Desipramine 25 mg/day administered in the evening. Dosing may be increased dependent upon side-effects and clinical response to a maximum of 100 mg/day. Absent significant side-effects, all patients are increased at the one week visit to 50 mg/day at bedtime if they have not achieved a report of "Adequate relief". Thereafter, up to week 4, the daily desipramine dose may be increased weekly by 25 mg up to the 100 mg/d maximum.	IBS-Low Somatization (Open Label Desipramine) IBS patients with low somatization (IBS-S-, ) IBS defined by Rome III, somatization by low PHQ-15 Desipramine: Desipramine 25 mg/day administered in the evening. Dosing may be increased dependent upon side-effects and clinical response to a maximum of 100 mg/day. Absent significant side-effects, all patients are increased at the one week visit to 50 mg/day at bedtime if they have not achieved a report of "Adequate relief". Thereafter, up to week 4, the daily desipramine dose may be increased weekly by 25 mg up to the 100 mg/d maximum.
Overall Study STARTED	10	8
Overall Study COMPLETED	5	4
Overall Study NOT COMPLETED	5	4

Reasons for withdrawal

Reasons for withdrawal
Measure	IBS-High Somatization (Open Label Desipramine) IBS patients with high somatization (IBS-S+, ) IBS defined by Rome III, somatization by high PHQ-15. Desipramine: Desipramine 25 mg/day administered in the evening. Dosing may be increased dependent upon side-effects and clinical response to a maximum of 100 mg/day. Absent significant side-effects, all patients are increased at the one week visit to 50 mg/day at bedtime if they have not achieved a report of "Adequate relief". Thereafter, up to week 4, the daily desipramine dose may be increased weekly by 25 mg up to the 100 mg/d maximum.	IBS-Low Somatization (Open Label Desipramine) IBS patients with low somatization (IBS-S-, ) IBS defined by Rome III, somatization by low PHQ-15 Desipramine: Desipramine 25 mg/day administered in the evening. Dosing may be increased dependent upon side-effects and clinical response to a maximum of 100 mg/day. Absent significant side-effects, all patients are increased at the one week visit to 50 mg/day at bedtime if they have not achieved a report of "Adequate relief". Thereafter, up to week 4, the daily desipramine dose may be increased weekly by 25 mg up to the 100 mg/d maximum.
Overall Study Subject did not initiate desipramine therapy	5	4

Baseline Characteristics

Irritable Bowel Syndrome (IBS) Functional Magnetic Resonance Imaging (fMRI) With Desipramine

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	IBS-High Somatization n=10 Participants Desipramine: Desipramine 25 mg/day administered in the evening. Dosing may be increased dependent upon side-effects and clinical response to a maximum of 100 mg/day. Absent significant side-effects, all patients are increased at the one week visit to 50 mg/day at bedtime if they have not achieved a report of "Adequate relief". Thereafter, up to week 4, the daily desipramine dose may be increased weekly by 25 mg up to the 100 mg/d maximum.	IBS-Low Somatization n=8 Participants Desipramine: Desipramine 25 mg/day administered in the evening. Dosing may be increased dependent upon side-effects and clinical response to a maximum of 100 mg/day. Absent significant side-effects, all patients are increased at the one week visit to 50 mg/day at bedtime if they have not achieved a report of "Adequate relief". Thereafter, up to week 4, the daily desipramine dose may be increased weekly by 25 mg up to the 100 mg/d maximum.	Total n=18 Participants Total of all reporting groups
Age, Continuous	43.2 years STANDARD_DEVIATION 13.65 • n=270 Participants	42.38 years STANDARD_DEVIATION 14.05 • n=4 Participants	42.84 years STANDARD_DEVIATION 13.42 • n=9 Participants
Sex: Female, Male Female	10 Participants n=270 Participants	8 Participants n=4 Participants	18 Participants n=9 Participants
Sex: Female, Male Male	0 Participants n=270 Participants	0 Participants n=4 Participants	0 Participants n=9 Participants
Race (NIH/OMB) American Indian or Alaska Native	0 Participants n=270 Participants	0 Participants n=4 Participants	0 Participants n=9 Participants
Race (NIH/OMB) Asian	0 Participants n=270 Participants	0 Participants n=4 Participants	0 Participants n=9 Participants
Race (NIH/OMB) Native Hawaiian or Other Pacific Islander	0 Participants n=270 Participants	0 Participants n=4 Participants	0 Participants n=9 Participants
Race (NIH/OMB) Black or African American	1 Participants n=270 Participants	3 Participants n=4 Participants	4 Participants n=9 Participants
Race (NIH/OMB) White	9 Participants n=270 Participants	5 Participants n=4 Participants	14 Participants n=9 Participants
Race (NIH/OMB) More than one race	0 Participants n=270 Participants	0 Participants n=4 Participants	0 Participants n=9 Participants
Race (NIH/OMB) Unknown or Not Reported	0 Participants n=270 Participants	0 Participants n=4 Participants	0 Participants n=9 Participants
Region of Enrollment United States	10 Participants n=270 Participants	8 Participants n=4 Participants	18 Participants n=9 Participants

PRIMARY outcome

Timeframe: 1 month

Outcome measures

Outcome measures
Measure	IBS-High Somatization n=10 Participants IBS patients with elevated PHQ-15	IBS-Low Somatization n=8 Participants IBS patients with normal PHQ-15
MRI Blood Oxygen Level Dependent (BOLD) Activation CONTRASTS (in Prespecified Regions of Interest (ROI) in VOXELS Left insula activation contrast, Montreal Neurological Institute x,y,z coordinates (-28.5, 9, 19.5)	0.02 arbitrary unit Standard Deviation 0.045	-0.09 arbitrary unit Standard Deviation 0.07
MRI Blood Oxygen Level Dependent (BOLD) Activation CONTRASTS (in Prespecified Regions of Interest (ROI) in VOXELS Right insula activation contrast, Montreal Neurological Institute x,y,z coordinates (27, -1.5, 15)	0.02 arbitrary unit Standard Deviation 0.04	-0.09 arbitrary unit Standard Deviation 0.06

Adverse Events

IBS-High Somatization

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

IBS-Low Somatization

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

Healthy Controls

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Adverse event data not reported

Additional Information

Gregory Sayuk

Washington University School of Medicine

Phone: 314-454-8201

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee
Publication restrictions are in place