Sensitivity-Based Sequential Therapy for Helicobacter pylori

The efficacy of standard triple therapy for eradication of Helicobacter pylori infection has been decreasing as resistance of the organism to antibiotics has increased, and no alternative regimen has yet demonstrated superior effectiveness. Investigators in Taiwan randomized 900 patients with documented H. pylori infection to receive 14-day sequential therapy consisting of lansoprazole (30 mg) and amoxicillin (1 g) twice daily for 7 days, followed by lansoprazole (30 mg), clarithromycin (500 mg), and metronidazole (500 mg) twice daily for 7 days; 10-day sequential therapy consisting of the above regimens for 5 days each; or standard triple therapy consisting of the above dosages of lansoprazole, amoxicillin, and clarithromycin for 14 days. Antibiotic sensitivity was assessed in patients with available data (61%).

In an intention-to-treat analysis, eradication rates for 14-day sequential therapy, 10-day sequential therapy, and standard triple therapy were 90.7%, 87.0%, and 82.3%, respectively. Only the 14-day sequential therapy and standard triple therapy groups had significantly different eradication rates (P=0.003). Antibiotic resistance (clarithromycin for all three groups and metronidazole for the sequential groups) was associated with lower eradication rates. A decision analysis of projected efficacy rates in settings with varying levels of antibiotic resistance suggested that 14-day sequential therapy would be most efficacious unless clarithromycin resistance was very low (<5%) and metronidazole resistance was very high (>80%).