Efficacy of Potassium-Competitive Acid Blockers in Barrett's Esophagus (PCAB BE Study)

This is a prospective open-label study of PCAB in adults aged 18 years or older with nondysplastic Barrett's esophagus (NDBE) on maintenance PPI therapy. At the time of enrollment, participants will continue their usual PPI (any brand), standardized to once daily dosing for at least 7 days. After ≥7 days on once daily dosing, participants will undergo ambulatory 24-hour pH impedance testing without interruption of PPI therapy. After pH testing is complete, PPIs will be discontinued and replaced with vonoprazan 20 mg once daily for 7-28 days. After ≥7 days, 24-hour pH impedance testing will be repeated without interruption of vonoprazan therapy. Participants will complete a 30 day safety follow-up after the last dose of vonoprazan. Following completion of the follow-up visit, the patient's participation in the trial will end. Safety will be monitored throughout the study via assessing adverse events and conducting pregnancy and liver function testing.

Participants will complete the validated Gastroesophageal Reflux Disease-Health Related Quality of Life (GERD-HRQL) questionnaire prior to each pH study to assess symptom burden. Additionally, a health history questionnaire assessing comorbidities, concurrent medications, and past acid suppressive regimens, will be collected.

PPIs and PCABs are FDA-approved but their efficacy has not been compared in the NDBE sub-group enrolled on this study, an open-label prospective cohort without a control arm is the most appropriate and feasible study design as the study aims to compare two treatment methods in the same participant. Because participants will be used as their own comparator, a placebo arm is not needed. Furthermore, maintenance of patients with known BE on a placebo may induce reflux esophagitis.

Inclusion criteria

• Adults aged 18 or older at time of consent.
• Able to read and understand English and provide written informed consent.
• History of Gastroesophageal Reflux Disease (GERD) with or without heartburn.
• Diagnosed with nondysplastic Barrett's Esophagus (NBDE) defined as meeting the following within the past 3 years:

• Endoscopically confirmed BE with segment length ≥2 cm (to avoid those with an irregular Z line), and
• Histologic evidence of intestinal metaplasia without dysplasia ("dysplasia" includes indefinite for dysplasia).
• Currently on proton pump inhibitor (PPI) maintenance therapy, defined as PPI prescribed once or twice daily for 3 or more months (defined as 90 days or more) from consent. Any formulation and dosage of PPI will be included, including pantoprazole, omeprazole, esomeprazole, lansoprazole, rabeprazole, dexlansoprazole or their generic equivalents.
• If currently on twice daily PPI, then able to modify PPI regimen to once daily dosing as part of their routine clinical care.
• Ability to take oral medication and willing to adhere to study intervention regimen.
• Willing to follow lifestyle recommendations as outlined in protocol section 5.3

Exclusion criteria

• Barrett's Esophagus (BE) with dysplasia (indefinite for dysplasia, or low-grade dysplasia, or high-grade dysplasia) diagnosed within 12 months of study entry.
• Current or prior esophageal adenocarcinoma (EAC).
• Use of other acid suppressive medications.
• H. pylori diagnosis or treatment within the past 6 months prior to study entry.
• History of upper gastrointestinal tract surgery (e.g., esophagectomy or surgery for reflux disease).
• Current contraindication to 24hr pH impedance test, including:

• Recent broken nose, nasal surgery, or known deviated septum; or
• Bleeding disorders or those taking certain blood-thinning medications and unable to temporarily discontinue use per current clinical guidance may also be excluded due to increased risk of bleeding during catheter insertion; or
• Individuals with implanted devices like pacemakers or defibrillators.
• Known hypersensitivity or allergic reaction to any component of the study intervention.
• Treatment with another investigational product within 30 days prior to consent.
• Current use of rilpivirine-containing products.
• Pregnant, breastfeeding, or considering becoming pregnant or intending to donate ova during the study and for 30 days after the last dose of study drug.