ABSTRACT
BACKGROUND: While the superiority of proton pump inhibitors (PPIs) over histamine-2 receptor antagonists in symptom control of gastroesophageal reflux disease (GERD) has been well established, limited work has been done comparing the efficacy of different PPIs. Theoretically, differences in pharmacokinetic properties, such as increased bioavailability of lansoprazole, could play a role in efficacy of symptom control. The purpose of this study was to demonstrate a difference between PPIs in GERD symptom control.
POPULATION STUDIED: The patient population for this study consisted of 3510 individuals over age 18 years with endoscopically confirmed erosive esophagitis of grade 2 severity or higher who were gathered through a large multicenter clinical trial. To enter the study, patients had to have experienced at least 1 episode of moderate to very severe heartburn within 3 days before their screening visit. Comparison of treatment groups showed the only significant demographic difference was increased reported tobacco use in the omeprazole group (28%) versus the lansoprazole group (25%).
STUDY DESIGN AND VALIDITY: This study was a double-blind multicenter clinical trial in which participants were randomized to receive either 30 mg lansoprazole or 20 mg omeprazole once daily for 8 weeks. Allocation concealment was not mentioned. Follow-up visits were conducted at the end of weeks 1, 2, and 8 of treatment. Analysis was by intention to treat.
OUTCOMES MEASURED: This study looked primarily at onset and duration of symptom relief and severity as recorded by patients in a diary. Specifically, daytime and nighttime heartburn symptoms were analyzed with regard to percentage of complete heartburn relief as well as average heartburn severity at days 1 to 3 and the end of weeks 1, 2, and 8 of treatment.
RESULTS: The group treated with lansoprazole showed a statistically significant advantage in symptom relief throughout the treatment period. On day 1 of treatment, the lansoprazole group was found to be 33% heartburn free as compared with 25% in the omeprazole group (P < .0001). The number needed to treat (NNT) to see this statistically significant difference was 12.5. Patients receiving lansoprazole versus omeprazole had small but statistically significant decreases in numbers of heartburn-free days (56% vs 49% in first 3 days of treatment, NNT = 14) and nights (NNT = 14) as well as daytime heartburn severity and nighttime severity. The lansoprazoletreated group also showed increased sustained resolution of symptoms over the omeprazole-treated group during the 8-week study period. Overall, however, these differences were extremely small and narrowed as the study progressed to 8 weeks.
Lansoprazole provided a small but sustained advantage over omeprazole in the treatment of heartburn. However, although statistically significant, these differences in efficacy are minor and diminished over the 8-week course of treatment. In deciding to use one PPI over another, clinicians should consider other factors, primarily cost or availability.