The current study is designed to demonstrate the non-inferiority of CJ-12420-based triple therapy (CJ-12420, amoxicillin and clarithromycin) versus lansoprazole-based triple therapy (lansoprazole, amoxicillin and clarithromycin) in H. pylori eradication rate and to evaluate the safety of CJ-12420 following oral administration of either triple therapy twice daily for 7 days in H. pylori positive patients.

This is a double blind, randomized, active controlled, phase 3 study. Subjects will be randomly assigned to one of the two treatment groups (CJ-12420 50mg, lansoprazole 30mg). All subjects will be asked to take 5 tablets include clarithromycin, amoxicillin twice a day for 7 days.

After the treatment, UBT test will be conducted to confirm the Helicobacter pylori eradication.

Inclusion Criteria:

• H. pylori-positive at screening
• Complain of gastric discomfort symptom

Exclusion Criteria:

• Having received prior therapy for eradication of H. pylori
• Prior use of proton pump inhibitors (PPIs), H2 receptor blockers, at a full dosage within 14 days
• Prior use of H. pylori eradication effective antibiotics, bismuth within 14 days