A Novel Compound for Alcoholism Treatment: A Translational Strategy - Part II

Objective: 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. Study population: The study population will be AUD individuals (n = 55). Study Design: A within-subject, counterbalanced, double-blind, placebo-controlled study. Outcome measures: The primary aim will be to determine whether PF-05190457, compared to placebo, reduces alcohol cue-elicited craving. As another outcome will be to determine whether PF-05190457, compared to placebo, reduces brain blood oxygen level dependent (BOLD) response during exposure to alcohol cues, during a task-based fMRI scan. We will also investigate the effects of PF-05190457 on food craving as well as on food choices using a virtual buffet experimental procedure. All these outcomes will be assessed in the inpatient Unit at the NIH Clinical Center (CC). After the inpatient portion of the protocol, patients will be followed-up as outpatients. During the outpatient phase, patients will be offered motivational interviewing and video feedback to explore the effects of this intervention, compared to supportive counseling, on maintaining motivation for alcohol abstinence and inform future studies where medications like PF-05190457 and behavioral treatments may be combined. The outpatient phase is optional for treatment seeking and nontreatment seeking participants.