10 Day Concomitant Versus 14 Day Hybrid Regimen as First Line H. Pylori Eradication Treatment in a High Clarithromycin Resistance Area. A Multicenter Randomized Equivalence Trial

RESEARCH PROTOCOL:

TITLE "10 day concomitant versus 14 day hybrid regimen as first line H. pylori eradication treatment in a high clarithromycin resistance area. A multicenter, randomized, equivalence trial."

INTRODUCTION

Helicobacter pylori (H. pylori) is a global human pathogen implicated in the pathogenesis of prevalent and serious diseases mainly peptic ulcer disease and gastric malignancy.1 Recent guidelines propose H. pylori eradication every time that it is found with the usual detection methods.2 Successful eradication largely depends on the choice of antibiotics in which the microbe is mostly sensitive.3 Usual first line therapies contained a proton pump inhibitor (PPI) and two antibiotics, clarithromycin with amoxicillin or metronidazole when amoxicillin wasn't indicated.4 Eradication rates have been initially acceptable reaching over 80% in per protocol analyses.5,6 However in late years H. pylori has developed an increasingly high resistance profile which has reached over 20% in most European countries, including ours. As a consequence, eradication rates with triple regimens declined to percentages less than 80% in per protocol analyses.7-9 Currently acceptable schemes include the already known bismouth containing quadruple regimen and the non bismouth quadruples namely concomitant, sequential and hybrid.10,11 In our country the 10 days concomitant regimen presents stable and high eradication rates which are significantly better than the standard triple and sequential regimens of the same duration.12-14 In two recent studies concomitant had a significant advantage over sequential on metronidazole resistant strains as well as on dual resistant to both clarithromycin and metronidazole strains.14,15 The hybrid regimen is the less studied first line regimen in Europe.16 In a recent study, on a Greek population, a 14 days hybrid regimen achieved encouraging results and the only predictive factor for failure has been dual resistance.17 To date there hasn't been any comparative study between 10 days concomitant and 14 days hybrid regimens.16

PURPOSE OF STUDY The investigators designed an equivalence trial between the 10 days concomitant and 14 days hybrid regimens in a Greek population.The investigators primary outcome is to compare total eradication rates between these two regimens in intention to treat and per protocol analyses. Secondary outcomes are to compare eradication rates in respect to genotypic and phenotypic resistance profiles, the effect of antibiotic resistance on therapy, patient's compliance, adverse events and economic evaluation of the two regimens.