Clarithromycin-amoxycillin-containing triple therapy: a valid empirical first-line treatment for Helicobacter pylori eradication in Hong Kong?

Background: Recent studies have suggested the eradication rate for Helicobacter pylori infection with standard amoxycillin-clarithromycin-containing triple therapy as first-line treatment have fallen below 80%. Levofloxacin-containing triple therapy was proposed as an alternative. The aim of this study is to compare the efficacy and tolerability of the standard 7-day clarithromycin-containing triple therapy against the 7-day levofloxacin-containing triple therapy, and to assess whether the classical triple therapy is still valid as empirical first-line treatment for H. pylori infection in Hong Kong.

Methods: Three hundred consecutive H. pylori-positive patients were randomized to receive either 1 week of EAL (esomeprazole 20 mg b.d., amoxycillin 1 g b.d., and levofloxacin 500 mg daily) or EAC (esomeprazole 20 mg b.d., amoxycillin 1 g b.d., and clarithromycin 500 mg b.d.). H. pylori status was rechecked by (13)C-urea breath test 6 weeks after treatment. Patients who failed either of the first-line eradication therapy were invited to undergo H. pylori susceptibility testing.

Results: H. pylori eradication was achieved in 128 of 150 (85.3%) patients in EAL and 139 of 150 (92.7%) patients in EAC groups, respectively (p = .043), for both intention-to-treat and per-protocol analysis. More patients in the clarithromycin- than the levofloxacin-containing therapy group developed side effects from the medication (21.3% vs 13.3%, p = .060). Nine patients (six from the EAL group and three from the EAC group) who failed their corresponding eradication therapy returned for susceptibility testing. All nine isolates were highly resistant to levofloxacin (minimum inhibitory concentration or MIC > 32 microg/mL), whereas only two of the six isolates from the EAL group were resistant to clarithromycin (MIC > 0.5 microg/mL).

Conclusions: The standard 7-day clarithromycin-containing triple therapy is still valid as the most effective empirical first-line eradication therapy for H. pylori infection in Hong Kong, as prevalence of primary resistance of H. pylori to amoxycillin and clarithromycin remains low. Patients who failed their empirical first-line eradication therapy should undergo H. pylori susceptibility testing to guide further treatment.