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Methylnaltrexone (MOA-728)
Methylnaltrexone is a peripheral mu-opioid receptor antagonist that blocks opioid receptors in the gastrointestinal tract without crossing the blood-brain barrier, thereby reversing opioid-induced constipation while preserving central analgesia.
Methylnaltrexone is a peripheral mu-opioid receptor antagonist that blocks opioid receptors in the gastrointestinal tract without crossing the blood-brain barrier, thereby reversing opioid-induced constipation while preserving central analgesia. Used for Opioid-induced constipation in patients with chronic non-cancer pain, Opioid-induced constipation in patients with advanced illness receiving palliative care.
At a glance
| Generic name | Methylnaltrexone (MOA-728) |
|---|---|
| Sponsor | Bausch Health Americas, Inc. |
| Drug class | Peripheral mu-opioid receptor antagonist |
| Target | Mu-opioid receptor (peripheral) |
| Modality | Small molecule |
| Therapeutic area | Gastroenterology / Supportive Care |
| Phase | Phase 3 |
Mechanism of action
Methylnaltrexone is a quaternary ammonium derivative of naltrexone that selectively antagonizes mu-opioid receptors on the enteric nervous system. Because it is highly polar and does not cross the blood-brain barrier, it acts peripherally to counteract the constipating effects of opioids on gut motility without reducing analgesia. This mechanism allows patients to maintain pain relief while experiencing restored bowel function.
Approved indications
- Opioid-induced constipation in patients with chronic non-cancer pain
- Opioid-induced constipation in patients with advanced illness receiving palliative care
Common side effects
- Abdominal pain
- Diarrhea
- Nausea
- Flatulence
- Dizziness
Key clinical trials
- Study Evaluating Oral MOA-728 For The Treatment Of OIBD In Subjects With Chronic Non-Malignant Pain (PHASE2)
- Study Evaluating the Efficacy and Safety of Subcutaneous Methylnaltrexone (MOA-728) for the Treatment of Opioid-Induced-Constipation (PHASE3)
- Study Evaluating Safety & Efficacy of Subcutaneous Methylnaltrexone on Opioid-Induced Constipation in Cancer Subjects (PHASE4)
- Study Evaluating Subcutaneous MOA-728 for the Treatment of Opioid-Induced Constipation (OIC) in Subjects With Chronic Non-Malignant Pain (PHASE3)
- Study Evaluating IV Methylnaltrexone for the Treatment of Post Operative Ileus (PHASE3)
- Study Evaluating Long-Term Safety of MOA-728 in Participants With Opioid-Induced Constipation (PHASE3)
- A Study Evaluating Intravenous (IV) MOA-728 for the Treatment of Postoperative Ileus (POI) in Participants After Ventral Hernia Repair (PHASE3)
- Study Evaluating Subcutaneous Methylnaltrexone For Treatment Of Opioid-Induced Constipation In Patients With Advanced Illness (PHASE4)
Primary sources
Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.
| Source | Used for |
|---|---|
| ClinicalTrials.gov | Trial enrolment, design, endpoints, results |
Competitive intelligence
For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape:
- Methylnaltrexone (MOA-728) CI brief — competitive landscape report
- Methylnaltrexone (MOA-728) updates RSS · CI watch RSS
- Bausch Health Americas, Inc. portfolio CI