Phathom Pharmaceuticals Completes Patient Enrollment in Phase 3 PHALCON-NERD-301 Daily Dosing Trial of Vonoprazan in Non-Erosive Gastroesophageal Reflux Disease

Phathom Pharmaceuticals, Inc. recently announced it has completed enrollment in its PHALCON-NERD Daily Dosing Phase 3 trial of vonoprazan in non-erosive gastroesophageal reflux disease (NERD). Vonoprazan is an investigational first-in-class potassium-competitive acid blocker (PCAB) from a novel class of medicines that block acid secretion in the stomach. The company expects to share topline data from the primary endpoint in the first quarter of 2023 and full results from the study in late 2023.

If successful, Phathom believes that the trial will form the basis of a supplemental New Drug Application (sNDA) for vonoprazan as once daily therapy for the treatment of symptomatic NERD in adults in 2023.

NERD is the largest subcategory of gastroesophageal reflux disease (GERD) and is characterized by reflux-related symptoms in the absence of esophageal mucosal erosions. There are estimated to be over 65 million individuals with GERD in the US, and it is estimated that 70% of this population have NERD.

The primary endpoint of the double-blind Phase 3 PHALCON-NERD-301 study is evaluating the efficacy of vonoprazan 10 mg and 20 mg as a daily dosing (QD) treatment, as compared to placebo (QD), in the relief of heartburn over four weeks in participants with symptomatic NERD. The trial also includes a unique blinded 20-week long-term extension period to further evaluate the safety and efficacy of both doses of vonoprazan after six months.

“NERD is a highly prevalent acid-related disorder that impacts the overall quality of life of millions of people and can present painful and chronic symptoms including episodic heartburn and chest pain,” said Azmi Nabulsi, MD, Chief Operating Officer at Phathom. “We are pleased to have marked another milestone with the completion of enrollment in our Phase 3 daily dosing trial of vonoprazan in NERD, bringing Phathom another step closer to provide a much-needed novel therapy for a disease that has not seen a new class of therapeutics introduced in the US in over 30 years. We look forward to sharing the topline results in the first quarter of 2023.”

Phathom is also currently in discussions with FDA on a second Phase 3 trial design to support the novel dosing regimen for vonoprazan as an on-demand or “as needed” treatment for episodic heartburn relief in patients with NERD, a dosing treatment regimen not approved in the US for proton pump inhibitors (PPIs).

Phathom Pharmaceuticals is a biopharmaceutical company focused on the development and commercialization of novel treatments for gastrointestinal diseases and disorders. Phathom has in-licensed the exclusive rights in the US, Europe, and Canada to vonoprazan, a first-in-class potassium-competitive acid blocker (PCAB). Vonoprazan-based regimens are approved in the US as part of a co-packaged product in combination with antibiotics for the treatment of H. pylori infection in adults, marketed as VOQUEZNA TRIPLE PAK (vonoprazan, amoxicillin, clarithromycin) and VOQUEZNA DUAL PAK (vonoprazan, amoxicillin). Phathom has a New Drug Application under review by the FDA for vonoprazan in erosive esophagitis (EE) and is studying the use of vonoprazan for the treatment of non-erosive reflux disease (NERD). For more information, visit www.phathompharma.com.