Phase II, Randomized, Placebo-Controlled Study of ATI-7505 in Patients With Chronic Idiopathic Constipation

Inclusion Criteria: * written informed consent * 18 and 75 years of age * constipation symptom onset at least 6 months ago \& meet ROME III criteria for chronic constipation * negative colonoscopy or air contrast barium enema within the past 2 years if ≥50 years of age or within the past 5 years if \<50 years of age; * are able to refrain from use of medications known to treat constipation or associated symptoms throughout the study Exclusion Criteria: * transabdominal surgery, unstable coronary artery disease, organic gastrointestinal disease, collagen vascular disease, or any alarm symptoms within the 6 months prior to screening; * taking prohibited medications (including laxatives, herbal remedies) * participating in another drug or medical device study or use of any investigational drug within 30 days before dosing or planning to use prior to study completion; * QTcB \>440 msec, abnormal 12-lead ECG, family history of sudden death at age \<40 years or history of long QT syndrome * alcohol or drug abuse within the 6 months prior to screening; * autonomic dyssynergic defecation