Evaluation of the Efficacy and Safety of Lubiprostone in Adults With Mixed or Unsubtyped Irritable Bowel Syndrome

A Randomized, Double-blind, Placebo-Controlled, Multicenter Study of the Efficacy and Safety of Lubiprostone in Adult Subjects With Mixed or Unsubtyped Irritable Bowel Syndrome (IBS-M/IBS-U)

A study of the efficacy and safety of Lubiprostone in subjects diagnosed with IBS-M/IBS-U.

To assess the efficacy and safety of oral lubiprostone, as compared to matching placebo, when administered orally (at 8 mcg twice daily [BID]) in subjects diagnosed with IBS-M/IBS-U.

Inclusion Criteria:

• Subject meets the diagnosis of IBS-M or IBS-U as confirmed using the adapted ROME III Diagnostic Questionnaire for Adult Functional GI Disorders.
• Subject Screening diary entries must show an average worst abdominal pain in the past 24 hours score of at least 4 on a 11-point scale.
• Subject must be on a stable dose of selective serotonin re-uptake inhibitors (SSRIs), serotonin-specific reuptake inhibitor (SNRIs), or monoamine oxidase inhibitors (MAO) inhibitors if taking antidepressants.

Exclusion Criteria:

• Subject has current diagnosis of IBS with diarrhea (IBS-D) or IBS with constipation (IBS-C), according to Rome III Criteria.
• Any gastrointestinal (GI) condition, other than IBS-related, affecting GI motility or defecation.
• Medical/surgical condition that might interfere with the absorption, distribution, metabolism, or excretion of the study medication.