The Efficacy of Potassium-Competitive Acid Blocker Compared With Double Dose of Proton Pump Inhibitor in Patients With Refractory Gastro-Esophageal Reflux Disease: A Case-Control Study.

Objectives: A significant number of patients with gastroesophageal reflux disease (GERD) experience refractory symptoms despite conventional doses of a proton pump inhibitor (PPI). Potassium-competitive acid blockers (PCABs) directly inhibit H+,K+-ATPase in a reversible manner and more profoundly inhibit acid secretion. However, the efficacy of PCABs in the treatment of refractory symptoms has not been thoroughly studied. Methods: This consecutive study was conducted between March 2020 and March 2023; patients with refractory symptoms were enrolled. Esophagogastroduodenoscopy, ambulatory esophageal pH measurements, and manometry were performed. Double split doses of rabeprazole (20 mg) or tegoprazan (50 mg) were prescribed for 2 weeks, and the symptoms were subsequently evaluated. A positive response was defined as more than 50% improvement in the visual analog scale scores for symptom severity. Results: A total of 63 patients were enrolled. In the group that received a double split dose of PPI (n=33), the positive response rate was 63.6% (21/33). There were 18 cases of abnormal acid exposure (excessive esophageal acid exposure time [AET] >4.0%); the positive response rate was 50.0% (9/18). In the group treated with PCAB (n=30), the positive response rate was 80.0% (24/30) (p=0.15). There were 19 cases of abnormal acid exposure; the positive response rate was 84.2% (16/19). The difference was statistically significant in favor of the PCAB group (p=0.02). Conclusions: In patients with refractory GERD symptoms, PCAB therapy had effects corresponding to those of a double split dose of PPIs. PCAB therapy was therefore deemed superior to PPIs, especially in patients with abnormal AETs.