title: Challenging the dogma: a randomized trial of standard vs. half-dose concomitant nonbismuth quadruple therapy for Helicobacter pylori infection.
abstract: BACKGROUND
  Current treatment of Helicobacter pylori consists of three or four drugs for 7-14 days with important associated cost and adverse events.
  
  
  OBJECTIVE
  This study compared efficacy and safety of standard dose vs. half-dose concomitant nonbismuth quadruple therapy (NBQT) for 7 days. The standard dose consisted of twice daily rabeprazole 20 mg, amoxicillin 1 g, metronidazole 500 mg, and clarithromycin 500 mg.
  
  
  METHODS
  This was a prospective randomized trial. (14)C-urea breath test was performed ≥4 weeks after treatment and ≥2 weeks off acid suppressive therapy. Compliance and adverse events were monitored during treatment.
  
  
  RESULTS
  A total of 200 consecutive treatment-naïve patients were enrolled. Baseline characteristics were similar between groups, with 15.5% of subjects reporting prior macrolide use. Eradication occurred in 78% (95% CI 68.6-85.7%) in both groups on intention-to-treat analysis. Per-protocol rates were 82.1 vs. 83.9% for standard-dose patients vs. half-dose patients, respectively (p = NS). Adverse events (only mild) were reported in 57 vs. 41% of standard-dose patients vs. half-dose patients (p = 0.024), with metallic taste and nausea notably less frequent in the latter (36 vs. 12% and 18 vs. 7%, respectively; p < 0.05 for both). Overall, eradication failed in 38.7% of prior macrolide users vs. 18.9% without such exposure (p = 0.019). On multivariate logistic regression, prior macrolide exposure was the only factor associated with failed eradication (OR 2.60, 95% CI 1.06-6.39; p = 0.038). Treatment was cheaper with the half-dose regimen.
  
  
  CONCLUSIONS
  A 50% reduction in antibiotic dosage does not diminish efficacy of concomitant nonbismuth quadruple therapy but leads to significant reduction in cost and adverse events. Seven-day concomitant NBQT is suboptimal for H. pylori independent of prior macrolide exposure.
authors.affiliation: Division of Gastroenterology, Department of Internal Medicine, American University of Beirut Medical Center, Beirut, Lebanon.
authors.forename: Ala I
authors.initials: AI
authors.lastname: Sharara
authors.affiliation: Division of Gastroenterology, Department of Internal Medicine, American University of Beirut Medical Center, Beirut, Lebanon.
authors.forename: Fayez S
authors.initials: FS
authors.lastname: Sarkis
authors.affiliation: Division of Gastroenterology, Department of Internal Medicine, American University of Beirut Medical Center, Beirut, Lebanon.
authors.forename: Mustapha M
authors.initials: MM
authors.lastname: El-Halabi
authors.affiliation: Division of Gastroenterology, Department of Internal Medicine, American University of Beirut Medical Center, Beirut, Lebanon.
authors.forename: Ahmad
authors.initials: A
authors.lastname: Malli
authors.affiliation: Division of Gastroenterology, Department of Internal Medicine, American University of Beirut Medical Center, Beirut, Lebanon.
authors.forename: Nabil M
authors.initials: NM
authors.lastname: Mansour
authors.affiliation: Division of Gastroenterology, Department of Internal Medicine, American University of Beirut Medical Center, Beirut, Lebanon.
authors.forename: Cecilio
authors.initials: C
authors.lastname: Azar
authors.affiliation: Division of Gastroenterology, Department of Internal Medicine, American University of Beirut Medical Center, Beirut, Lebanon.
authors.forename: Mohamad A
authors.initials: MA
authors.lastname: Eloubeidi
authors.affiliation: Division of Gastroenterology, Department of Internal Medicine, American University of Beirut Medical Center, Beirut, Lebanon.
authors.forename: Fadi H
authors.initials: FH
authors.lastname: Mourad
authors.affiliation: Division of Gastroenterology, Department of Internal Medicine, American University of Beirut Medical Center, Beirut, Lebanon.
authors.forename: Kassem
authors.initials: K
authors.lastname: Barada
authors.affiliation: Division of Gastroenterology, Department of Internal Medicine, American University of Beirut Medical Center, Beirut, Lebanon.
authors.forename: Ismail
authors.initials: I
authors.lastname: Sukkarieh
keywords: Adverse events; dyspepsia; eradication; gastritis; pylori