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.