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Study to Evaluate the Efficacy, Safety, and Tolerability of BOS-589 in the Treatment of Patients With Diarrhea-predominant Irritable Bowel Syndrome (IBS-D)

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Boston Scientific

Status and phase

Completed
Phase 2

Conditions

Diarrhea-predominant Irritable Bowel Syndrome

Treatments

Drug: BOS-589
Drug: Placebo

Study type

Interventional

Funder types

Industry

Identifiers

NCT03977155
BOS-589-201

Details and patient eligibility

About

This study is being conducted to evaluate in participants with diarrhea-predominant Irritable Bowel Syndrome (IBS-D) the abdominal pain response to BOS-589 after 4 weeks of treatment and to evaluate the overall safety and tolerability of BOS-589 in the treatment of IBS-D during 4 weeks of treatment, relative to placebo (PBO).

Enrollment

133 patients

Sex

All

Ages

18 to 65 years old

Volunteers

No Healthy Volunteers

Inclusion criteria

  • Participant meets the diagnosis of diarrhea-predominant IBS (IBS-D) subtype based on Rome IV diagnostic criteria within 3 months prior to randomization. On days when the participant experiences IBS symptoms

    • At least 25% of stools are loose or watery; and
    • Fewer than 25% of stools are hard.
  • Recurrent abdominal pain occurring, on average, at least 1 day per week and associated with 2 or more of the following:

    • Related to defecation;
    • Associated with a change in frequency of bowel movements;
    • Associated with a change in form (appearance) of stool.
  • Over the week prior to randomization, the participant has

    • An average of worst abdominal pain (WAP) scores in the prior 24 hours of 4.0 to 8.0 on a 0 to 10 numerical rating scale;
    • An average daily Bristol Stool Form Scale (BSFS) score ≥ 5.0 (and at least 5 days with a BSFS score ≥ 5.0;
    • An average daily IBS-Global Scale (IBS-GS) score of ≥ 2.0.
  • Participant must undergo or previously have undergone (a) an appropriate evaluation for their IBS symptoms, including an evaluation for organic/structural etiologies (if in the presence of alarm symptoms); and (b) age-appropriate screening for colorectal cancer, if applicable.

  • Participant is negative for serum tissue transglutaminase immunoglobulin A antibody (tTG-IgA) plus has evidence of detectable serum IgA within the normal reference range.

Exclusion criteria

  • At the time of screening, participant has a diagnosis of an IBS subtype other than IBS-D, based on Rome IV criteria.

  • Participant has a history of inflammatory or immune-mediated gastrointestinal (GI) disorders including (but not limited to) inflammatory bowel disease (i.e., Crohn's disease, ulcerative colitis, microscopic colitis, and celiac disease).

  • Participant has had an episode of diverticulitis within 3 months prior to Screening.

  • Participant has a history of intestinal obstruction, stricture, toxic megacolon, GI perforation, fecal impaction, gastric banding, bariatric surgery, adhesions, ischemic colitis, or impaired intestinal circulation (e.g., aortoiliac occlusive disease).

  • Participant has any of the following surgical history:

    • Cholecystectomy with any history of post-cholecystectomy biliary tract pain;
    • Any abdominal surgery within the 3 months prior to Screening;
    • Major gastric, esophageal, hepatic, pancreatic, or intestinal surgery (appendectomy, hemorrhoidectomy, or polypectomy greater than 3 months post-surgery are allowed).
  • Confirmed alanine aminotransferase (ALT) > 2 upper limit of normal (ULN)

  • Confirmed total bilirubin > ULN, unless the participant has a documented history of Gilbert's syndrome

  • Evidence of active hepatitis B virus (HBV) or hepatitis C virus (HCV) infection or Human immunodeficiency virus (HIV)-1 or HIV-2 antibody positive

  • Evidence of HCV infection based on a positive HCV antibody screen (Participants who have been successfully treated for HCV are eligible if an undetectable HCV viral load at least 6 months after completion of treatment can be demonstrated.)

Trial design

Primary purpose

Treatment

Allocation

Randomized

Interventional model

Parallel Assignment

Masking

Triple Blind

133 participants in 3 patient groups, including a placebo group

High dose of BOS-589
Experimental group
Description:
Participants will receive a high dose of BOS-589 orally twice a day (BID).
Treatment:
Drug: BOS-589
Low dose of BOS-589
Experimental group
Description:
Participants will receive a low dose of BOS-589 orally BID.
Treatment:
Drug: BOS-589
Placebo
Placebo Comparator group
Description:
Participants will receive matching placebo orally BID.
Treatment:
Drug: Placebo

Trial documents
2

Trial contacts and locations

58

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Data sourced from clinicaltrials.gov

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