Last reviewed 2026-04-20 · How we verify

Entereg (ALVIMOPAN)

Alvimopan selectively antagonizes µ-opioid receptors in the gastrointestinal tract, improving motility without affecting central analgesia.

At a glance

Mechanism of action

Alvimopan works by blocking the µ-opioid receptors in the gut, which are responsible for slowing down gastrointestinal movement. By doing so, it helps speed up recovery from postoperative ileus without reducing the pain relief provided by opioids.

Approved indications

• Postoperative ileus

Boxed warnings

• WARNING: POTENTIAL RISK OF MYOCARDIAL INFARCTION WITH LONG-TERM USE: FOR SHORT-TERM HOSPITAL USE ONLY There was a greater incidence of myocardial infarction in alvimopan-treated patients compared to placebo-treated patients in a 12-month clinical trial, although a causal relationship has not been established. In short-term trials with alvimopan, no increased risk of myocardial infarction was observed [see Warnings and Precautions ( 5.1 )] . Because of the potential risk of myocardial infarction with long-term use, alvimopan is available only through a restricted program for short-term use (15 doses) under a Risk Evaluation and Mitigation Strategy (REMS) called the Alvimopan REMS Program [see Warnings and Precautions ( 5.1 , 5.2 )] . WARNING: POTENTIAL RISK OF MYOCARDIAL INFARCTION WITH LONG-TERM USE: FOR SHORT-TERM HOSPITAL USE ONLY See full prescribing information for complete boxed warning. Increased incidence of myocardial infarction was seen in a clinical trial of patients taking alvimopan for long-term use. ( 5.1 ) Alvimopan capsules are available only through a restricted program for short-term use (15 doses) called the Alvimopan REMS Program. ( 5.1 , 5.2 )

Common side effects

• dyspepsia

Drug interactions

• intravenous morphine
• acid blockers (PPIs, H2 receptor antagonists)
• antibiotics

Key clinical trials

• A Study of Surgical Techniques During Cystectomy (PHASE3)
• Alvimopan as a Rescue Treatment of Postoperative Ileus (PHASE4)
• Alvimopan Versus Placebo in Patients Undergoing Radical Cystectomy on an Enhanced Recovery Protocol (PHASE3)
• Alvimopan as Rescue in Post op Ileus (PHASE3)
• Phase 2 RCT of Alvimopan vs. Placebo After CRS/HIPEC (PHASE2)
• Trial of Alvimopan in Major Spine Surgery (PHASE4)
• Conventional VS Enhanced Recovery After Surgery Protocols in Emergency GIT Surgery
• Alvimopan Use in Polytraumatized Patients (PHASE4)

Patents

Primary sources

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Competitive intelligence

For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape:

• Entereg CI brief — competitive landscape report
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• Cubist Pharms portfolio CI