Objective: Ghrelin is a 28-aminoacid 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. Furthermore, findings from a translational human lab study at Brown University (PI: Leggio) indicate that intravenous (IV) ghrelin administration, compared to placebo, results in an acute increase in craving for alcohol during a cue-reactivity experiment in alcoholic individuals. Therefore, an orally bioavailable, ghrelin receptor antagonist, that can pass through the blood brain barrier holds particular promise as an AD treatment. This project has been recently funded by NCATS. The goals of this protocol are to generate preliminary evidence on the safety and efficacy of a ghrelin receptor antagonist (GHSR1a antagonist), PF-05190457, an existing molecule available under the NIH-Industry Pilot Program at NCATS.