Efficacy and safety of omeprazole in Japanese patients with nonerosive reflux disease.

BACKGROUND: There is increasing awareness of nonerosive reflux disease (NERD) as a disease requiring treatment in Japan. This randomized, double-blind, placebo-controlled, parallel-group study was conducted to investigate the efficacy and safety of omeprazole 10 mg and 20 mg once daily in Japanese patients with NERD. METHODS: Patients with heartburn for at least 2 days a week during the month before entry into the study and no endoscopic signs of a mucosal break (grade M or N according to Hoshihara's modification of the Los Angeles classification) were randomly assigned to one of three groups (omeprazole 10 mg or 20 mg, or placebo) once daily for 4 weeks. RESULTS: Overall, 355 patients were enrolled, of whom 284 were randomly assigned to one of the three groups (omeprazole 10 mg, n = 96; omeprazole 20 mg, n = 93; placebo, n = 95). The rate of complete resolution of heartburn in week 4 was significantly higher in patients treated with omeprazole 10 mg [32.3%, 95% confidence interval (CI), 22.9%-41.6%] or 20 mg (25.8%, 95% CI, 16.9%-34.7%) than in the placebo group (12.0%, 95% CI, 5.3%-18.6%). No significant difference between the two omeprazole groups was observed. The rate of complete resolution of heartburn by omeprazole was similar between patients with grade M and those with grade N esophagus. Omeprazole also increased the rate of sufficient relief from heartburn. Omeprazole was well tolerated. CONCLUSIONS: Omeprazole 10 mg or 20 mg once daily is effective and well tolerated in patients with NERD regardless of their endoscopic classification.

The pharmacodynamic effect of omeprazole 10 mg and 20 mg once daily in patients with nonerosive reflux disease in Japan.

BACKGROUND: To evaluate the pharmacodynamic effect, efficacy, and safety of omeprazole 10 mg and 20 mg once daily in patients with nonerosive reflux disease (NERD) in Japan. METHODS: A total of 37 patients were randomized to omeprazole 10 mg or omeprazole 20 mg once daily for 4 weeks. Eligible patients had a history of moderate-to-severe heartburn for 2 days or more per week during the last 1 month or longer prior to the study screening, grade M or grade N on Hoshihara's modification of the Los Angeles classification (i.e., no sign of mucosal break on esophagogastroduodenoscopy), and heartburn episodes for 2 days or more per week during the last week of the observation period while taking antacids. Ambulatory 24-h intraesophageal pH was monitored on the day before treatment and on the last day of treatment. The occurrence of a heartburn episode was recorded during pH monitoring. The primary endpoint was the change in the percentage of time with intraesophageal pH < 4 during the 24-h period before and after omeprazole treatment. RESULTS: Both omeprazole 10 mg and omeprazole 20 mg once daily reduced the percentage of time with intraesophageal pH < 4. The percentage reduction in time with intraesophageal pH < 4 after treatment with omeprazole was associated with a reduced number of heartburn episodes. Patients with grade M or grade N esophagus had similar pH profiles and NERD characteristics (e.g., pH holding time, symptom index) and comparable responses to omeprazole. No serious, drug-related adverse events were reported. CONCLUSIONS: Omeprazole 10 mg or 20 mg reduces the percentage of time with intraesophageal pH < 4, is efficacious, and is well tolerated in patients with NERD in Japan, regardless of the patient's endoscopic classification.