Naloxegol (Moventig®) is a peripherally acting µ -opioid receptor antagonist and is indicated for the treatment of opioid-induced constipation in patients who have had an inadequate response to laxatives. The number of weekly defecations is increased by 1 on average in patients who take 25 mg daily over 12 weeks. A marked placebo response is observed in 30% of patients, and the response improvement of 10-15% compared to placebo is considerably lower than expected. The sub-group with inadequate response to laxatives showed a response improvement of 15-20%. Quality of life measurements were made, but they were not designed with statistical power to show a difference between naloxegol and placebo in quality-of-life parameters. Regarding relief of gastrointestinal symptoms, significant improvement was only seen in rectal and faecal symptoms. The effect is independent of the opioid dose.
The most frequent adverse events include abdominal pain, diarrhoea, nausea, headache and flatulence. During treatment with naloxegol 25 mg over 12 weeks, 63.5% of the patients reported adverse events compared with 51.1% in the placebo group.
Comparative studies of naloxegol and other drugs of the same indication are not available.
Considering the modest effect compared with placebo and frequent adverse events, it is IRF’s overall assessment that the clinical relevance of naloxegol is not convincing and does not correlate with the high treatment price. Ordinary types of laxatives in optimal dose should be attempted before considering naloxegol. Naloxegol only has a second-line indication for the treatment of opioid-induced constipation. Patients should be informed about the modest effect. If the patient does not experience a satisfactory effect after short-term treatment, the treatment should be discontinued, because an effect should be expected as early as after one week of treatment.
Moventig was marketed on 2 February 2015, and single reimbursement may be applied for at present.