Inclusion Criteria:  Patients aged 18-70 with persistent H. pylori infection. Patients failed at least three different standard eradication therapies before.Previous standard eradication therapy was defined as a 10-day or 14-day quadruple regimen designed according to Maastricht V report.  Exclusion Criteria:  Patients treated with H2-receptor antagonist, PPI, vonoprazan,bismuth and antibiotics in the previous 4 weeks. Patients with gastorectomy, acute GI bleeding and advanced gastric cancer. History of allergy to any of the drugs used in the study. Severe concomitant cardiovascular, respiratory, or endocrine diseases,clinically significant renal or hepatic disease, hematologic disorders and any other clinically significant medical condition that could increase risk. Currently pregnant or lactating. Severe neurologic or psychiatric disorders. Alcohol abuse or drug addiction. Patients with compliance lower than 90% in any previous treatment are not included. Inability to provide informed consent and other situations that could interfere with the examination or therapeutic protocol.