Ghrelin is a 28-amino acid peptide that stimulates appetite and food intake. It is an endogenous ligand for the growth hormone secretagogue receptor (GHSR1a). Preclinical studies suggest that ghrelin modulates alcohol reward processing. Previous work from our research team, indicated that intravenous (IV) ghrelin administration, compared to placebo, results in an acute increase in alcohol craving during a cue-reactivity experiment in alcoholic individuals. Therefore, an oral bioavailable, ghrelin receptor antagonist that is able to pass through the blood brain barrier holds particular promise as a treatment for alcohol use disorder (AUD). This protocol is part of a grant project funded by National Center for Advancing Translational Sciences (NCATS) aimed to generate preliminary evidence in AUD on the safety and efficacy of a ghrelin receptor (GHSR1a) antagonist, PF-05190457, an existing molecule available under the NIH-Industry Pilot Program at NCATS. Completed preclinical and clinical (Protocol #14-AA-0042) work has demonstrated the safety of PF-05190457/alcohol interaction. The goal of this protocol is to conduct a proof-of-concept human laboratory study to assess an early-signal of efficacy of PF-05190457 in AUD.