1. Participants who completed the initial treatment with PPIs (esomeprazole, omeprazole, rabeprazole, or lansoprazole) and have received high dose PPIs (esomeprazole 20 mg, omeprazole 20 mg, rabeprazole 10 mg, or lansoprazole 30 mg) for more than 8 weeks at the time of informed consent as maintenance treatment for LA Classification Grades A to D reflux esophagitis.