Review of the clinical development of fexuprazan for gastroesophageal reflux-related disease.

Proton pump inhibitors (PPIs) are a mainstay treatment for acid peptic disorders such as gastroesophageal reflux disease (GERD). Although PPIs are considered first-line medications for acid suppression, they have notable limitations such as requiring acid-mediated activation, short half-life and duration of action, and metabolic variability. Fexuprazan is a newly developed potassium-competitive acid blocker (P-CAB), which inhibits acid generation and secretion in a competitive and reversible manner. Fexuprazan, like other P-CABs, has significantly different pharmacodynamic and pharmacokinetic properties than PPIs with potential advantages including rapid, robust, and durable acid suppression, lack of CYP2C19 metabolism, independence from food intake, and no requirement for activation into an active form. Completed clinical trials of fexuprazan have demonstrated comparable efficacy to PPIs for the healing of erosive esophagitis and relief of GERD-related esophageal symptoms without concerning safety signals. Ongoing clinical trials are evaluating fexuprazan for the prevention of NSAID-induced peptic ulcer disease, non-erosive GERD, and acute and chronic gastritis, as well as healing efficacy and maintenance of erosive esophagitis (EE). Fexuprazan is approved in South Korea for the treatment of EE and at the time of this writing is being considered for regulatory approval in several other countries. In this article, we summarize and discuss the pharmacology, efficacy, and safety of fexuprazan.