The opioid system modulator nalmefeneis the first pharmacological therapy approved in the European Union for reduction of alcohol consumption.

To evaluate the clinical relevance of the reduction of alcohol consumption in patients with at least high drinking risk level at screening and randomisation from the two, identically designed, randomised controlled 6-month studies ESENSE1 (NCT00811720) and ESENSE2 (NCT00812461) of nalmefene versus placebo.

Study medication was taken as-needed. All patients received a motivational and adherence-enhancing intervention (BRENDA). Response criteria were based on alcohol consumption at month 6 and Clinical Global Impression – Severity of Illness/Improvement (CGI-S/I), Short Form Health Survey version 2 (SF-36) mental component summary(MCS) scores at week 24. Clinical relevance was also studied using the Drinker Inventory of Consequences (DrInC), Alcohol Dependence Scale (ADS), and liver function variables.

Pooled study population: 667 patients (placebo N=332; nalmefene N=335). The proportion of responders was higher in the nalmefene group than in the placebo group with odds ratios for response consistently significantly (p<0.05) in favour of nalmefene. The difference in the proportions of responders translated to numbers-needed-to-treat ranging from 6 to 10. Significant differences to placebo (p<0.05) in the SF-36 MCS and physical component summary score, ADS, DrInC, CGI-I/S and liver enzymes further supported the clinical relevance of the treatment effect.

In view of the immense alcohol-related burden to society, the harm to the individual and the large treatment gap partly due to a reluctance to engage in abstinence, the effect of nalmefene is clearly clinically relevant.