The part of adjunctive treatment with N-acetylcysteine (NAC) in standard first-line triple therapy for Helicobacter pylori infection is poorly known. This study comprised of the antibiotic susceptibility data from the study participants to provide a possibility to examine whether NAC affects the antimicrobial resistance. As found, NAC did not have an additive effect on the H. pylori eradication rate along with triple therapy. 

This randomized controlled trial intended to compare the efficacy of clarithromycin triple therapy for 14 days with or without NAC for the first-line treatment of H. pylori.

A total of 680 patients suffering from H. pylori infection naïve to therapy were registered in this trial. These patients were randomized to receive triple therapy (T14, dexlansoprazole 60 mg every day; amoxicillin 1 g twice daily, clarithromycin 500 mg twice daily) for 2 weeks; and triple therapy plus NAC [NAC-T14, dexlansoprazole 60 mg four times daily; amoxicillin 1 g twice daily, clarithromycin 500 mg twice daily, NAC 600 mg twice daily] for 2 weeks. The eradication rates by intention to treat (ITT) was considered as the primary outcome. The CYP2C19 gene polymorphism and antibiotic resistance were ascertained.

As per the ITT analysis, H. pylori eradication rates in NAC-T14 and T14 were 81.7% and 84.3%, respectively. Treatment adherence was observed in 646 participants. The eradication rates were 85.7% and 88.0% with NAC-T14 and T14 treatments. No differences in compliance or adverse effects were witnessed. The eradication rates in patients with clarithromycin-resistant, amoxicillin-resistant, or either clarithromycin/amoxicillin resistant strains in both the therapies have been portrayed in below table:

The efficiency of NAC-T14 and T14 was not influenced by CYP2C19 polymorphism.

For first-line H. pylori eradication, the use of add-on NAC to triple therapy was not found superior to triple therapy alone.