MedPageToday -- A four-drug regimen over 10 days worked as well as the three-drug, seven-day regimen that’s the standard ulcer treatment and may help overcome the growing problem of antibiotic resistance, researchers reported. In a randomized, open-label phase III trial of 440 patients, the four-drug combo -- a proton pump inhibitor plus a single capsule containing bismuth subcitrate potassium, metronidazole, and tetracycline -- was found to be noninferior to clarithromycin (Biaxin), omeprazole, and amoxicillin, according to Peter Malfertheiner, MD, of Otto-von-Guericke-Universtitat in Magdeburg, Germany, and colleagues.