We conducted a open-labeled, prospective, randomized, controlled study in a large tertiary referral hospital in Eastern Taiwan. Hp-positive therapy-naïve patients with a positive CLO test as proven by gastroscopy were recruited for potential random assignment to two 7-day treatment groups: LAcR or CAR (control). The primary end point of this study was to evaluate the eradication rate of LAcR regimen. Hp eradication was assessed using the 13C-urea breath test or CLO test performed at least 4 weeks after end of treatment. Compliance and adverse effects with therapy were determined by phone call or outpatient clinic follow up.