FDA Approves Novel Therapy for Gastroesophageal Reflux

The FDA has approved Phathom Pharmaceuticals’ Voquezna (vonoprazan) tablets to treat adults with erosive esophagitis, also known as erosive GERD (gastroesophageal reflux disease). It is also indicated as a maintenance therapy for erosive GERD and for the relief of heartburn associated with erosive GERD.

Erosive GERD affects about 20 million people in the United States. Patients with inadequately treated erosive GERD may develop more severe diseases including Barrett’s esophagus, a condition in which esophageal tissue changes can progress to cancer.

Voquezna is a novel potassium-competitive acid blocker (PCAB), which has a mechanism similar to proton pump inhibitors but with a more rapid action and that doesn’t require dosing 30 minutes before meals. Voquezna is expected to be available in December 2023.

The wholesale acquisition cost (WAC) of Voquezna tablets is $650 for both (10 mg and 20 mg) 30-count bottles. Phathom is also offering programs for commercial patients who face coverage or affordability issues, including co-pay assistance. The company has already secured commercial coverage with 65% commercial lives covered.

“For many GERD patients with erosive Eesophagitis, the response to current treatment is suboptimal, leaving them with incomplete healing and ongoing symptoms,” Colin W. Howden, M.D., professor emeritus, University of Tennessee College of Medicine, said in a press release.

The approval is based on results from the phase 3 PHALCON-EE study, which enrolled 1,024 patients with erosive GERD. The study compared Voquezna to the proton pump inhibitor lansoprazole in the healing and maintenance of healing of erosive GERD. Study results, which were published in October 2022 in Gastroenterology, showed that Voquezna was non-inferior to lansoprazole with complete healing by week. Patients with all grades of Erosive GERD with a healing rate of 93% compared with 85% for lansoprazole 30 mg. Voquezna also demonstrated non-inferiority to lansoprazole in the mean percentage of 24-hour heartburn free days over the healing period.

In the maintenance phase of the trial, Voquezna was superior to lansoprazole 15 mg in maintaining healing at six months in all randomized patients (79% for Voquezna, compared with 72% for lansoprazole) as well as in the subset of patients with moderate-to-severe erosive GERD (75% for Voquenza compared to 61% for lansoprazole.

Adverse events were comparable for both therapies. The most common adverse events in the healing phase were gastritis, diarrhea, abdominal distention, abdominal pain, and nausea. The most common adverse events in the maintenance phase were gastritis, abdominal pain, dyspepsia, hypertension and urinary tract infection.