Phathom Pharmaceuticals, Inc. has received approval from the FDA for VOQUEZNA (vonoprazan) tablets in 10 mg and 20 mg doses. This novel potassium-competitive acid blocker (PCAB) is now available as a new treatment option for adults dealing with the healing of all grades of Erosive Esophagitis, also known as Erosive GERD (gastroesophageal reflux disease), as well as for maintaining healing of all grades of Erosive GERD, and providing relief from associated heartburn.
Erosive GERD, also referred to as Erosive Esophagitis or Erosive Acid Reflux, is a significant form of GERD affecting around 20 million people in the U.S. Inadequately treated Erosive GERD can lead to more severe conditions such as Barrett’s esophagus, which has the potential to progress to cancer.
This FDA approval is based on promising results from the Phase 3 PHALCON-EE study (NCT04124926). This pivotal trial, involving 1,024 patients with Erosive GERD in the U.S. and Europe, compared VOQUEZNA to the PPI lansoprazole in terms of healing and maintenance of healing of Erosive GERD, as well as relief from associated heartburn symptoms.
The study revealed that VOQUEZNA 20 mg achieved the primary goal of non-inferiority (p<0.0001) for complete healing by Week 8 in patients with all grades of Erosive GERD, with a healing rate of 93% compared to 85% for lansoprazole 30 mg. Superior healing rates were also observed in a secondary endpoint for patients with moderate-to-severe disease (LA Grade C/D) at Week 2 compared to lansoprazole (70% for VOQUEZNA 20 mg and 53% for lansoprazole 30 mg) (p=0.0008). Furthermore, VOQUEZNA 20 mg demonstrated non-inferiority to lansoprazole 30 mg in the mean percentage of 24-hour heartburn free days over the healing period. In the maintenance phase, VOQUEZNA 10 mg outperformed lansoprazole 15 mg in maintaining healing at six months for all randomized patients (79% for VOQUEZNA 10 mg vs. 72% for lansoprazole 15 mg) as well as for patients with moderate-to-severe Erosive GERD (75% for VOQUEZNA 10 mg vs. 61% for lansoprazole 15 mg) (p=0.0490). Additionally, VOQUEZNA 10 mg demonstrated non-inferiority to lansoprazole 15 mg in providing relief from heartburn in Erosive GERD patients over six months.
Adverse event (AE) rates for VOQUEZNA were similar to those for lansoprazole in the trial. The most common AEs during the healing phase (≥ 2% in the VOQUEZNA treatment group) were gastritis (3.0% for VOQUEZNA 20 mg and 2.0% for lansoprazole 30 mg), diarrhea (2.0% for VOQUEZNA 20 mg and 3.0% for lansoprazole 30 mg), abdominal distension (2.0% for VOQUEZNA 20 mg and 1.0 % for lansoprazole 30 mg), abdominal pain (2.0% for VOQUEZNA 20 mg and 1.0% for lansoprazole 30 mg) and nausea (2.0% for VOQUEZNA 20 mg and 1.0% for lansoprazole 30 mg). In the maintenance phase, the most common AEs (≥ 3% in the VOQUEZNA treatment group) for VOQUEZNA 10 mg compared to lansoprazole 15 mg were gastritis (6.0% vs. 3.0%), abdominal pain (4.0% vs. 2.0%), dyspepsia (4.0% vs. 3.0%), hypertension (3.0% vs. 2.0%), and urinary tract infection (3.0% vs. 2.0%).
VOQUEZNA is expected to be available in the U.S. starting December 2023 and will be exclusively marketed by Phathom Pharmaceuticals, Inc.
Additionally, based on the terms of Phathom’s revenue interest financing agreement, the FDA approval of VOQUEZNA for Erosive GERD entitles the company to receive a $175.0 million payment, providing non-dilutive capital for funding the commercial launch.