An Open Label Trial of Duloxetine in the Treatment of Irritable Bowel Syndrome and Comorbid Generalized Anxiety Disorder
|Irritable Bowel Syndrome Generalized Anxiety Disorder||Drug: Duloxetine||Phase 4|
|Study Design:||Intervention Model: Single Group Assignment
Masking: Single Blind (Participant)
Primary Purpose: Treatment
|Official Title:||An Open Label Trial of Duloxetine in the Treatment of Irritable Bowel Syndrome and Comorbid Generalized Anxiety Disorder|
- Clinical Global Impression Scale [ Time Frame: endpoint [12 weeks] ]
The scale consists of two parts the first part being Severity of Illness and the second part is Global Improvement. We report the Global improvement scale.
The Global Improvement is a 1-7 change scale of global improvement since inclusion in the project ranging with 1 "very much improved", 4 "no change", and 7 "very much worse."
- Hamilton Anxiety Rating Scale [ Time Frame: endpoint [12 weeks] ]The HAM-A is a 14 question scale with five responses. Responses range from 0 "not present" to 4 "very severe." The total score ranges from 0 to 56. Higher values represent a worse outcome.
- Irritable Bowel Syndrome-Quality of Life Scale [ Time Frame: endpoint [12 weeks] ]The IBS-QOL consists of 34 items, each with a five-point response scale. Ratings range from 1 "not at all" to 5 "extremely" or "a great deal" Higher responses on the scale indicate worse outcome. A minimal total score would be 34, maximum 170.
- Irritable Bowel Syndrome Severity Scoring System [ Time Frame: endpoint [12 weeks] ]This is a 4 item Likert scale with each assessment being 100 mm scored from measuring from 0 to 400. Higher numbers indicate worse outcome.
|Study Start Date:||September 2009|
|Study Completion Date:||December 2011|
|Primary Completion Date:||December 2011 (Final data collection date for primary outcome measure)|
Two weeks of placebo run in followed by 12 weeks of Duloxetine.
All subjects will receive single-blind placebo for the first two weeks, and then duloxetine for the next 12 weeks, followed by an up to 2 week taper off of the duloxetine. After 2 weeks of placebo daily, subjects will receive 30 mg per day of duloxetine for two weeks, then titrated up to 60 mg per day of duloxetine at week 2. A dosage decrease to 30 mg daily is permittable after week 2. This will be a flexible dose study with doses of duloxetine progressively increasing at weeks 4 (90 mg daily) and 6 (120 mg daily) in conjunction with CGI-I scores, to reach 120 mg daily or the maximum tolerated dose, if less than 120 mg daily at Week 12. There will be a post-taper follow up appointment at Week 14. Of Note: Amendment IRB Approved 6/14/11 Study Ending at Week 12 with removal of Week 14 visit as part of study.
Other Name: Cymbalta
Generalized Anxiety Disorder (GAD) is commonly associated with Irritable Bowel Syndrome(IBS). The etiology of IBS remains unknown and it is often refractory to treatment. Duloxetine has demonstrated efficacy in the treatment of GAD as well as other pain disorders including fibromyalgia and diabetic neuropathy.
We plan to study 30 subjects with diagnoses of IBS and GAD between the ages of 18 and 65 years. There will be a single-blind placebo-run-in for the first 2 weeks, followed by open-label duloxetine for 12 weeks flexibly titrated to 120 mg/day. Subjects will be informed that they will receive placebo for 2 weeks during the trial. All study visits will be at Allegheny General Hospital Department of Psychiatry. The study consists of a total of nine office visits.
Please refer to this study by its ClinicalTrials.gov identifier: NCT00961298
|Principal Investigator:||Alicia J Kaplan, MD||West Penn Allegheny Health System|