In this issue of the European Journal of Internal Medicine, Johnson, Addolorato and colleagues [1,2] report the efficacy and safety results of a phase 3, multicenter double-blind placebo-controlled clinical trial of a low dose of the serotonin-3-receptor (5HT3) antagonist, ondansetron (called AD04-ondansetron in this Commentary) in the treatment of 303 participants with DSM V alcohol use disorder (AUD). The study duration was 6 months. In addition to the medication, all participants received a manualized psychosocial alcohol treatment, Brief Behavioral Compliance Enhancement Treatment (BBCET) every two weeks.