Randomized, Double-blind, Dose-range-finding, Phase 2 Study of Linaclotide Administered to Patients With Irritable Bowel Syndrome With Constipation (IBS-C)
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ClinicalTrials.gov Identifier: NCT00460811 |
Recruitment Status :
Completed
First Posted : April 16, 2007
Results First Posted : January 30, 2013
Last Update Posted : February 4, 2013
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Condition or disease | Intervention/treatment | Phase |
---|---|---|
Irritable Bowel Syndrome With Constipation | Drug: Linaclotide Acetate Drug: Matching placebo | Phase 2 |
Study Type : | Interventional (Clinical Trial) |
Actual Enrollment : | 420 participants |
Allocation: | Randomized |
Intervention Model: | Parallel Assignment |
Masking: | Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor) |
Primary Purpose: | Treatment |
Official Title: | A Randomized, Multicenter, Double-blind, Placebo-controlled, Dose-range-finding, Parallel-design, Phase 2 Trial of Oral Linaclotide Acetate Administered to Patients With Irritable Bowel Syndrome With Constipation |
Study Start Date : | April 2007 |
Actual Primary Completion Date : | February 2008 |
Actual Study Completion Date : | April 2008 |

Arm | Intervention/treatment |
---|---|
Active Comparator: 72 ug linaclotide acetate |
Drug: Linaclotide Acetate
Oral, once daily |
Active Comparator: 145 ug linaclotide acetate |
Drug: Linaclotide Acetate
Oral, once daily |
Active Comparator: 290 ug linaclotide acetate |
Drug: Linaclotide Acetate
Oral, once daily |
Active Comparator: 579 ug linaclotide acetate |
Drug: Linaclotide Acetate
Oral, once daily |
Placebo Comparator: Matching Placebo |
Drug: Matching placebo
Oral, once daily |
- Change From Baseline in the Weekly Normalized Complete Spontaneous Bowel Movement (CSBM) Rate During Weeks 1 Through 12 of the Treatment Period [ Time Frame: Change from Baseline to Week 12 ]
The change in the weekly normalized CSBM Rate during Weeks 1 through 12 of the Treatment Period from the weekly normalized CSBM Rate obtained during the Pretreatment Period.
The CSBM rate was normalized based on the number of CSBMs occurring in that week, adjusting for differences in the duration of the week and black-out periods (time not covered due to a missed IVRS call) versus 7x24 hours.
- CSBM 75% Responder for the Treatment Period (Based on the Normalized Rate) [ Time Frame: Change from Baseline to Week 12 ]For each week of the Treatment and Posttreatment Periods, a patient was considered a CSBM Responder if for that week the patient 1) completed ≥ 4 days of IVRS questions, 2) had a CSBM rate of ≥ 3 for the week, and 3) had an increase in CSBM rate of ≥ 1 from the baseline weekly CSBM rate.
- Change From Baseline in the Weekly Normalized SBM Rate for the Treatment Period [ Time Frame: Change from Baseline to Week 12 ]SBMs were measured daily during the treatment period by patient calls to the IVRS.
- Change From Baseline in Stool Consistency (7-point Ordinal BSFS) for the Treatment Period [ Time Frame: Change from Baseline to Week 12 ]Stool consistency analyses were performed using the 7-point Bristol Stool Form Scale (BSFS), whereby a score of 1 = separate hard lumps like nuts (difficult to pass); 2 = sausage shaped but lumpy; 3 = like a sausage but with cracks on surface; 4 = like a sausage or snake, smooth and soft; 5 = soft blobs with clear-cut edges (passed easily); 6 = fluffy pieces with ragged edges, a mushy stool; and 7 = watery, no solid pieces (entirely liquid).
- Change From Baseline in Straining (5-point Ordinal Scale) for the Treatment Period [ Time Frame: Change from Baseline to Week 12 ]Straining was assessed using a 5-point ordinal scale, whereby a score of 1 = not at all, 2 = a little bit, 3 = a moderate amount, 4 = a great deal, and 5 = an extreme amount.
- Change From Baseline in Degree of Relief of Irritable Bowel Syndrome (IBS) Symptoms (7-point Balanced Scale) for the Treatment Period [ Time Frame: Change from Baseline to Week 12 ]Patients provided a weekly assessment of Degree of Relief of IBS Symptoms using a 7-point balanced scale (1=completely relieved, 2=considerably relieved, 3=somewhat relieved, 4=unchanged, 5=somewhat worse, 6=considerably worse, 7=as bad as I can imagine).
- Change From Baseline in Abdominal Pain (5-point Ordinal Scale) for the Treatment Period [ Time Frame: Change from Baseline to Week 12 ]During the study, patients provided their self assessment of abdominal pain using a 5-point ordinal scale (1=none, 2=mild, 3=moderate, 4=severe, 5=very severe

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Ages Eligible for Study: | 18 Years and older (Adult, Older Adult) |
Sexes Eligible for Study: | All |
Accepts Healthy Volunteers: | No |
Inclusion Criteria:
- Must not be pregnant or breastfeeding and agree to use birth control;
- Completion of a negative colonoscopy as per American Gastroenterology Association (AGA) criteria and no clinically-significant laboratory or physical examination findings;
- Meets protocol-defined criteria for IBS-C, including stool frequency, straining, stool consistency, abdominal pain, and abdominal discomfort criteria;
- Demonstrates English fluency and has access to a touch-tone telephone.
Exclusion Criteria:
- Recent history of mushy or watery stools;
- Various medical conditions, medical histories, or family medical histories that would not make the patient a good candidate for the study;
- Clinically-significant alarm symptoms;
- Secondary causes of constipation or evacuation disorders;
- Surgery to the gastrointestinal tract;
- Usage of prohibited medications.

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT00460811

Study Director: | Microbia Medical Director, MD | Microbia, Inc. |
Responsible Party: | Ironwood Pharmaceuticals, Inc. |
ClinicalTrials.gov Identifier: | NCT00460811 |
Other Study ID Numbers: |
MCP-103-202 |
First Posted: | April 16, 2007 Key Record Dates |
Results First Posted: | January 30, 2013 |
Last Update Posted: | February 4, 2013 |
Last Verified: | January 2013 |
Irritable Bowel Syndrome with Constipation IBS Irritable Bowel Syndrome |
linaclotide acetate linaclotide MD-1100 |
Irritable Bowel Syndrome Syndrome Constipation Disease Pathologic Processes Signs and Symptoms, Digestive Colonic Diseases, Functional Colonic Diseases |
Intestinal Diseases Gastrointestinal Diseases Digestive System Diseases Linaclotide Guanylyl Cyclase C Agonists Enzyme Activators Molecular Mechanisms of Pharmacological Action Gastrointestinal Agents |