Adults who are taking opioid therapy for persistent non-cancer pain and have resulting opioid-induced bowel dysfunction (OBD) will be randomized (1:1:1) to one 2 alvimopan arms, or to placebo. The primary objective of this phase 3 confirmatory study is to compare alvimopan with placebo for efficacy in the treatment of OBD. The primary efficacy endpoint is based on frequency of bowel movements. Subjects will be required to: (1) track their bowel movements and other bowel symptoms and (2) attend 6 clinic visits over 4 months.

Inclusion criteria:

• Has consented to participate in this study.
• Taking opioid therapy for persistent non-cancer pain.
• Has bowel dysfunction mainly due to opioids.
• Has bowel dysfunction since starting opioids as defined by infrequent bowel movements and additional bowel-related symptoms.
• Willing to discontinue laxative therapy (will be provided study-specific standardized laxative if needed).
• Willing to report daily bowel symptoms.

Exclusion criteria:

• Pregnant, lactating, or planning to become pregnant.
• Not ambulatory.
• Participated in another trial with an investigational drug in the past 30 days.
• Taking opioids for the management of drug addiction or cancer-related pain.
• Severe constipation whereby the subject is at immediate risk of developing serious complications of constipation.
• Gastrointestinal or pelvic disorders known to affect bowel transit, produce gastrointestinal (GI) obstruction, or contribute to bowel dysfunction.
• HIV-infected, has active hepatitis, or has ever been infected with hepatitis C.