Increasing the duration of dual amoxicillin plus omeprazole Helicobacter pylori eradication to 6 weeks: a pilot study

Helicobacter pylori infections have become increasingly difficult to treat as antimicrobial resistance has increased. The aim of this study was to test the hypothesis that a 6-week dual regimen of amoxicillin 1 gm and omeprazole 20 gm therapy b.i.d. would cure at least 90% of treatment-naïve H. pylori infections.

This was an open-label prospective pilot study in which treatment-naïve subjects with active H. pylori infection (positive by two tests) received dual amoxicillin 1 g and omeprazole 20 mg, b.i.d. daily for 6 weeks. Success was accessed by urea breath test 4-6 weeks later. A tentatively effective therapy was defined as a per-protocol treatment success of 90% or greater; treatment success of 80% or less was prespecified as unacceptable.

Sixteen patients were included in the study (14 men, two women) with an average age of 49 years. At 16 patients, the prespecified stopping rule of six treatment failures was achieved (i.e. the 95% confidence interval excluded achieving the required 90% success rate even if 50 patients were entered). As per protocol, enrollment was stopped. Per-protocol and intention-to-treat treatment success were both 62.5% (95% confidence interval, 35-84%). Compliance was greater than 99%. Five patients (31%) reported side-effects, all of which were mild and none interrupted therapy.

Despite the theory and pre-existing data from Japan, in the USA, prolonging the duration of dual amoxicillin-PPI therapy did not improve treatment outcome in 90% or more of our patients.