The reviewers in this paper highlight that currently there are no trials comparing nalmefene with another medication and that none of these studies was performed in the specific population defined by the EMA approval of nalmefene, i.e., adults with alcohol dependence who consume more than 60 g of alcohol per day (for men) or more than 40 g per day (for women). In the meta-analysis monthly number of heavy drinking days (at 6 months and 1 year) and total alcohol consumption (at 6 months) were reduced with nalmefene compared to placebo. The authors report that an attrition bias could not be excluded due to more withdrawals for nalmefene for safety reasons and undertook a sensitivity anaylsis (using baseline observation carried forward). A related BMJ article also reviews this meta-analysis.
NICE currently recommends that nalmefene can be considered as an option for alcohol dependence in men who drink more than 7.5 units per day or women who drink more than 5 units per day and do not have physical withdrawal symptoms or need to stop drinking straightaway or completely. Nalmefene should only be taken if the person is also having ongoing support to change their behaviour to help them reduce their alcohol intake.