A diagnosis of significant gastrointestinal (GI) disorder such as bowel obstruction, fecal incontinence or rectal prolapse.

A history of active inflammatory bowel disease, irritable bowel syndrome, or megacolon within 6 months before the screening visit.

A history of malignancy, other than basal cell or squamous cell skin carcinoma, within 5 years before the screening visit.

A history of chronic constipation before initiation of opioid therapy.

Study Evaluating Long-Term Safety of MOA-728 in Participants With Opioid-Induced Constipation