Pilot Study to Assess the Effects of AV608 on Irritable Bowel Syndrome

Inclusion Criteria:

• Female, 18 to 65 years of age, inclusive
• Current diagnosis of Irritable Bowel Syndrome (IBS)
• Subjects 50 years of age or older must have had a barium enema and flexible sigmoidoscopy or a colonoscopy and provide a record of this test
• Willing to participate in this study as evidenced by a signed, written informed consent form (ICF)
• If female and of child-bearing potential, willing to avoid pregnancy and practice adequate birth control from the time of study enrollment through at least 30 days after the final dose of study medication
• If female, negative pregnancy test results
• Right handed
• Ambulatory outpatient
• Agrees to refrain from blood donation during the course of the study
• Written and oral fluency in the English language

Exclusion Criteria:

• Evidence of structural abnormality of the gastrointestinal tract or GI diseases/conditions
• Current evidence or diagnosis of peptic ulcer
• Endoscopic bowel evaluation with evidence of cancer, inflammatory bowel disease, or other structural disease
• History of abdominal surgery such as adhesion lysis or any gastrointestinal surgery
• History of gastroesophageal reflux disease not controlled by a stable dose of medication
• Any evidence of or treatment of malignancy within the previous 5 years
• Clinical evidence of any disease that may interfere with participation in the study
• Existence of surgical or medical conditions which interfere with the absorption, distribution, metabolism and excretion of the study drug
• Symptoms of a significant clinical illness within the 2 weeks prior to Screening
• Type 1 diabetes mellitus, insulin-dependent Type 2 diabetes mellitus, and thyroid disorders or other endocrine disorders that are not well controlled by appropriate therapy
• A QTc interval of greater than or equal to 450 msec at Screening
• Presence of a psychotic disorder, bipolar disorder, alcohol or substance dependence (other than nicotine dependence) or eating disorder within the previous year according to DSM-IV-TR criteria
• Seizure disorder
• Subjects who have previously participated in a clinical trial for AV608 (previously known as NKP608 and CGP608)
• Positive drug test result at Screening
• Use of investigational drugs, products or devices within 30 days prior to Screening
• Planned use of certain drugs during the study that affect the central nervous system, gastrointestinal motility, autonomic activity or pain sensation
• Use of pimozide, terfenadine, astemizole, or cisapride during the study
• Presence of moderate or severe allergy
• Regular intake of more than 2 units of alcohol per day
• Pregnant or breast feeding
• Subjects with morbid obesity
• Subjects with metal implants or large tattoo
• Any clinically significant abnormalities on the Screening physical examination, ECG or laboratory tests
• Members of the investigative staff or their immediate family members
• Any other condition that the investigator believes would jeopardize the safety or rights of the subject or would render the subject unable to comply with the study protocol
• Regular use of more than 10 cigarettes per day