Fourteen-day amoxicillin- or tetracycline-containing bismuth quadruple therapy versus 14-day metronidazole based triple therapy as a first-line treatment for clarithromycin resistant Helicobacter pylori infection : a multicenter randomized controlled trial

INTERVENTION: Drug : This study was a prospective, randomized controlled trial comparing three oral eradication regimens in patients with clarithromycin‐resistant Helicobacter pylori (H. pylori) infection. All medications were administered orally, and the treatment duration was 14 days for all three arms. Arm 1 (PAM regimen) consisted of rabeprazole 20 mg twice daily, amoxicillin 1,000 mg twice daily, and metronidazole 500 mg three times daily, constituting a triple therapy. Arm 2 (PAM‐B regimen) consisted of rabeprazole 20 mg twice daily, amoxicillin 1,000 mg twice daily, metronidazole 500 mg three times daily, and tripotassium dicitratobismuthate 300 mg (120 mg as Bi2O3) four times daily, constituting a quadruple therapy. Arm 3 (PBMT regimen) consisted of rabeprazole 20 mg twice daily, metronidazole 500 mg three times daily, tetracycline 500 mg four times daily, and tripotassium dicitratobismuthate 300 mg (120 mg as Bi2O3) four times daily, constituting a quadruple therapy. All three arms shared a common backbone of rabeprazole 20 mg twice daily and metronidazole 500 mg three times daily. The key differences between arms are as follows. The difference between the PAM and PAM‐B arms lies solely in the addition of bismuth (tripotassium dicitratobismuthate 300 mg four times daily) in the PAM‐B arm. The antibiotic components and their respective doses were kept identical across these two arms. Since bismuth is not classified as an antibiotic, this approach aims to enhance eradication efficacy without introducing an additional antibiotic agent, thereby minimizing the risk of promoting further antibiotic resistance. Both the PAM‐B and PBMT arms are bismuth‐containing quadruple regimens; however, they differ in the choice of the second antibiotic. The PAM‐B arm uses amoxicillin (1,000 mg CONDITION: Certain infectious and parasitic diseases PRIMARY OUTCOME: Helicobacter pylori eradication success rate assessed by intention‐to‐treat (ITT) and per‐protocol (PP) analyses SECONDARY OUTCOME: Incidence of treatment‐related adverse events during the eradication therapy period Medication compliance during the eradication therapy period INCLUSION CRITERIA: ? Adults aged 18 to 80 years of both sexes. ? Patients diagnosed with Helicobacter pylori infection via endoscopy, confirmed by at least one of the following methods: histology, rapid urease test, serology, or urea breath test. ? Patients with clarithromycin resistance confirmed by dual‐priming oligonucleotide polymerase chain reaction (DPO‐PCR). ? Patients who provided written informed consent after receiving a full explanation of the study objectives and procedures.