Phathom Pharmaceuticals, a late clinical-stage biopharmaceutical company focused on developing and commercialising novel treatments for gastrointestinal diseases, announced yesterday that it has started PHALCON-EE, the company's pivotal Phase three clinical trial of vonoprazan for both the healing and maintenance of healing of erosive esophagitis (EE) and the relief of heartburn.

PHALCON-EE is a randomised, double-blind, two-phase, multicentre Phase three trial that is planned to enrol around 1,000 patients with erosive esophagitis in the United States and Europe. The first phase of the trial is to assess the efficacy and safety of vonoprazan 20mg administered once-daily (QD) compared to lansoprazole 30mg QD for the healing of EE for up to eight weeks.

The second phase of the trial is to assess the efficacy and safety of vonoprazan 10mg QD and 20mg QD compared to lansoprazole 15mg QD for the maintenance of healing of EE for 24 weeks. Both phases will also assess heartburn symptoms.