Background Constipation is a condition with slow and incomplete bowel evacuation and a pathological increase in the digestive tract transit time. Constipation has a negative influence on the quality of life of cancer patients. The use of opioids is a frequent cause of non-obstructive constipation. The Norwegian Knowledge Centre for the Health Services was asked by The Norwegian Directorate of Health to evaluate efficacy, safety, cost effectiveness and ethical aspects regarding use of methylnaltrexone as adjuvant treatment in patients with cancer in palliative care.
Methods We searched for studies in several databases. Included studies were critically reviewed. The evidence base was evaluated using GRADE. A simple health economic model was developed using TreeAge software.
Results
We identified two relevant randomised controlled trials which compared methylnaltrexone to placebo, with a total of 287 patients. Methylnaltrexone was significantly more effective in terms of response within 4 hours, both following the initial dose as well as repeated doses. In the double blind period abdominal pain was the most common adverse effect.
We found a cost per quality adjusted life year of NOK 718 000. The sensitivity analyses showed that the results were particularly sensitive to the assumptions on quality of life, and the clinical evidence.
Ethically methylnaltrexone makes it possible to treat vulnerable patients. The treatment can also ease the care for these patients. Low efficiency calls for prioritization.
Conclusions Our review suggests that methylnaltrexone was more effective than placebo in terms of time to laxation. From an ethical point of view methylnaltrexone may contribute to help a vulnerable patient group and professionals in everyday care. Our health economic model nevertheless does not provide us with the grounds to conclude that the drug is cost-effective.
Keywords: Methylnaltrexone; Constipation; Neoplasms; Palliative Care; Economics, Medical; Relistor; health economy; pharmacoeconomics.
Copyright ©2009 by The Norwegian Institute of Public Health (NIPH).