Long-term safety and effectiveness of vonoprazan as maintenance therapy for reflux esophagitis in Japan: a 12-month post-marketing surveillance study

Background This study aimed to assess the safety and effectiveness of vonoprazan, a potassium-competitive acid blocker, as long-term maintenance therapy in patients with healed reflux esophagitis (RE) in real-world settings.Research design and methods This prospective, observational study enrolled patients with healed RE from 122 sites in Japan. Patients received daily oral vonoprazan 10 mg as maintenance treatment for 12 months. Safety was assessed by monitoring adverse events (AEs) and adverse drug reactions (ADRs), and effectiveness was evaluated by endoscopic RE recurrence and symptom severity.Results Of the 1237 enrolled patients, 1174 were included in the safety analysis. ADRs were reported in 2.3% of patients. ADRs included diarrhea, constipation, and abnormal hepatic function. The severity of symptoms improved over time, and of those with endoscopic findings, the RE recurrence was 4.0% (17/425). A total of four serious ADRs were reported in two patients, which led to death, comprising pneumonia, acute leukemia, myelodysplastic syndrome, and decreased platelet count.Conclusions This study demonstrates the effectiveness of vonoprazan in preventing RE recurrence during maintenance treatment in clinical practice. The incidence of ADRs was low, and no new safety signals were identified, supporting the established safety profile of vonoprazan.Clinical trial registration: NCT03214081; jRCT1080223147.