phathom pharmaceuticals, inc., a clinical-stage biopharmaceutical company, focuses on developing and commercializing treatments for gastrointestinal diseases. the company has the rights in the united states, europe, and canada to vonoprazan, a potassium-competitive acid blocker (p-cab) that blocks acid secretion in the stomach. it is also developing vonoprazan, which is in phase iii clinical trials for the treatment of erosive gastroesophageal reflux disease; and in combination with antibiotics for the treatment of helicobacter pylori infection. the company was incorporated in 2018 and is based in buffalo grove, illinois.