Poster Session II - A189 FIRST PROSPECTIVE CANADIAN DATA OF THE WORLD-WIDE REGISTRY ON <i>HELICOBACTER PYLORI</i> MANAGEMENT (WORLDHPREG)

Abstract Background It is still unclear what the optimal treatment regimen for Helicobacter. pylori (Hp) infection is. The Maastricht VI (2022) and ACG (2024) guidelines recommend bismuth-based quadruple therapy (proton pump inhibitor [PPI], bismuth-metronidazole-tetracycline [PBMT]) for 14 days as first-line therapy for Hp. PPI-amoxicillin-metronidazole-clarithromycin (PAMC) is also recommended as first-line therapy by the Toronto Consensus (2016) and Maastricht VI guidelines. PPI-amoxicillin-levofloxacin (PAL) and PPI-amoxicillin-rifabutin (PAR) are accepted rescue therapies for treatment failures. Aims To describe the success and adverse event rates of currently prescribed treatments for Hp in Canada. Methods Multicentre, prospective registry evaluating the decisions and outcomes of Hp management by Canadian gastroenterologists (Hp-CanadaReg, WorldHpReg’s partner). Local research ethics board approval was obtained at each recruiting site, and informed consent was obtained from all participants. Data were registered at AEG-REDCap e-CRF. Both treatment naïve and previously treated patients were eligible for the study. Treatment adherence and adverse events were recorded via telephone or in person interviews. A modified intention-to-treat (mITT) analysis was used, which includes all patients with at least one follow-up test-of-cure. Results Between August 2024 - October 2025, 112 patients were enrolled across Canada. The majority of patients were treatment naïve (85/112) and 81% (60/74) were cured (Table 1). For first-line treatments, 91% (39/43) of patients were cured with PAMC vs 100% (5/5) with PBMT. Across all lines, PAL was successful in 50% of patients (1/2), while PAR was successful in 50% (2/4). Among patients treated with PPI-amoxicillin-clarithromycin (PAC, n = 5), 67% were cured (2/3). At least one adverse event was experienced by 59% (52/88) of patients, including diarrhea (31%, 27/88), nausea (19%, 17/88), dysgeusia (15%, 13/88), and vomiting (11%, 10/88). Adverse events were reported by 57% (31/54) of PAMC- vs 68% (13/19) of PBMT-treated patients (p = 0.398). One serious adverse event occurred in a PAMC patient requiring hospitalization for complications secondary to suspected penicillin allergy. Most patients (95%, 106/112) received treatment for 14 days and 94% (73/78) completed treatment, taking &amp;gt;90% of the prescribed therapy. Conclusions These are the first results from patients enrolled in the prospective Canadian subcohort of the WorldHpReg. The two first-line quadruple therapies, PAMC and PBMT, achieved success rates above &amp;gt;90%. These data provide valuable insight into current Hp treatment practices across Canada and will help guide future efforts to optimize the effectiveness of different therapeutic first-line regimens. Funding Agencies None