Study Of Alvimopan Drug For Treatment Of Constipation Due To Prescription Pain Medication

Inclusion criteria: * Participant is in any stage of cancer but has a minimum life expectancy of at least 3 months at the time of the Screening Visit. * Participant is taking opioid therapy for persistent cancer pain. * Participant meets the definition of opioid-induced bowel dysfunction as follows: Since starting opioid therapy, the subject has had decreased bowel movement (BM) frequency and at least one of the following constipation symptoms \[sensation of incomplete evacuation, difficulty in expelling stool (straining), hard stools (abnormal stool consistency)\]. * Participant understands the procedures, agrees to participate in the study, and has signed and dated the informed consent form prior to the initiation of any study-related activities, including discontinuation of pre-study laxative regimen or other prohibited medications. * Participant is able and willing to comply with a daily paper diary and is capable of completing paper questionnaires at study visits. Exclusion criteria: * Participant is pregnant or lactating, or planning to become pregnant. * Participant is not ambulatory. * Participant has participated in another trial with an investigational drug (unapproved), device or procedure within 30 days of the Screening Visit. * Participant is unable to eat, drink, take/hold down oral medications. * Participant is taking opioids for the management of drug addiction. * Participant is unable or unwilling to discontinue the use of and/or refrain from using laxatives of all types and formulation at the Screening Visit and throughout the entire study. * Participant has severe constipation that has not been appropriately managed such that the subject is at immediate risk of developing serious complications of constipation. This would include a subject who has reported no bowel movement for 7 consecutive days prior to the Screening Visit. * Participant with gastrointestinal or pelvic disorders known to affect bowel transit, produce gastrointestinal (GI) obstruction, or contribute to bowel dysfunction. * Participant is currently taking vinca alkyloids or plans to take vinca alkyloids during the study. * Participant is currently undergoing abdominal radiation therapy and/or plans to undergo abdominal radiation therapy during the study. * Participant is human immunodeficiency virus (HIV)-infected, has active hepatitis (any subtype including ongoing chronic hepatitis B), or has ever been infected with hepatitis C.