Quinolone-based first, second and third-line therapies for Helicobacter pylori

Helicobacter pylori (H. pylori) is a very common bacterium that infects about 50% of the world population in urban areas and over 90% of people living in rural and developing countries. Fluoroquinolones, a class of antimicrobials, have been extensively used in eradication regimens for H. pylori. Levofloxacin is the most commonly used, and in second-line regimens, is one of the most effective options. However, an increasing resistance rate of H. pylori to fluoroquinolones is being observed, that will likely affect their effectiveness in the near future. Other novel fluoroquinolone molecules, such as moxifloxacin, sitafloxacin, gatifloxacin and gemifloxacin, have been proposed and showed encouraging results in vitro, although data on their clinical use are still limited. Further studies in large sample trials are needed to confirm their safety and efficacy profile in clinical practice.