title: High Efficacy of Finafloxacin on Helicobacter pylori Isolates at pH 5.0 Compared with That of Other Fluoroquinolones.
abstract: Finafloxacin is a novel fluoroquinolone with improved antimicrobial efficacy, especially in an acidic environment. The efficacy of finafloxacin for the inhibition of Helicobacter pylori infection was compared with the efficacies of levofloxacin and moxifloxacin at neutral and acidic pH. The impacts of gyrA point mutation on the efficacy of those three fluoroquinolones were also investigated. A total of 128 clinical H. pylori strains were utilized. MICs of levofloxacin, moxifloxacin, and finafloxacin were determined at pH 5.0 and pH 7.0 by the agar dilution method. The impact of gyrA point mutations that are responsible for fluoroquinolone resistance was analyzed; the results showed 50 strains with an Asn-87 point mutation, 48 strains with an Asp-91 point mutation, and the remaining 30 strains with no gyrA mutations. The use of finafloxacin led to MIC values at pH 5.0 that were lower than the values seen at pH 7.0 for 112 strains (112/128, 87.5%), and this proportion was higher than that seen with moxifloxacin (21/128, 16.4%, P < 0.001). Finafloxacin also demonstrated a rate of susceptibility (MIC, <1 μg/ml) (37.5%, 48/128) at pH 5.0 that was higher than that seen with moxifloxacin (2.3%, 3/128) (P < 0.001). The trends were similar regardless of which of the Asn-87, Asp-91, and A2143 point mutations were present. In conclusion, the superior antimicrobial efficacy of finafloxacin against H. pylori in an acidic environment suggests the possible use of finafloxacin for treatment of H. pylori infection, as has been proposed by its developer, Merlion Pharma.
authors.affiliation: Department of Internal Medicine, Seoul National University Bundang Hospital, Seongnam, Gyeonggi-do, South Korea Department of Internal Medicine and Liver Research Institute, Seoul National University College of Medicine, Seoul, South Korea.
authors.forename: Jung Won
authors.initials: JW
authors.lastname: Lee
authors.affiliation: Department of Internal Medicine, Seoul National University Bundang Hospital, Seongnam, Gyeonggi-do, South Korea Department of Internal Medicine and Liver Research Institute, Seoul National University College of Medicine, Seoul, South Korea nayoungkim49@empas.com.
authors.forename: Nayoung
authors.initials: N
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Seoul National University Bundang Hospital, Seongnam, Gyeonggi-do, South Korea.
authors.forename: Ryoung Hee
authors.initials: RH
authors.lastname: Nam
authors.affiliation: Department of Microbiology, Hanyang University School of Medicine, Seoul, South Korea.
authors.forename: Jung Mogg
authors.initials: JM
authors.lastname: Kim
authors.affiliation: School of Pharmacy, MCPHS University, Boston, Massachusetts, USA.
authors.forename: Jong Youn
authors.initials: JY
authors.lastname: Park
authors.affiliation: Department of Internal Medicine, Seoul National University Bundang Hospital, Seongnam, Gyeonggi-do, South Korea.
authors.forename: Sun Min
authors.initials: SM
authors.lastname: Lee
authors.affiliation: Department of Internal Medicine and Liver Research Institute, Seoul National University College of Medicine, Seoul, South Korea.
authors.forename: Joo Sung
authors.initials: JS
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Seoul National University Bundang Hospital, Seongnam, Gyeonggi-do, South Korea Department of Internal Medicine and Liver Research Institute, Seoul National University College of Medicine, Seoul, South Korea.
authors.forename: Dong Ho
authors.initials: DH
authors.lastname: Lee
authors.affiliation: Department of Internal Medicine and Liver Research Institute, Seoul National University College of Medicine, Seoul, South Korea.
authors.forename: Hyun Chae
authors.initials: HC
authors.lastname: Jung
mesh_terms: D019943:Amino Acid Substitution; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D001216:Asparagine / Q000378:metabolism; D001224:Aspartic Acid / Q000378:metabolism; D027081:DNA Gyrase / Q000235:genetics* / Q000378:metabolism; D005260:Female; D024841:Fluoroquinolones / Q000627:therapeutic use*; D015870:Gene Expression; D016481:Helicobacter Infections / Q000188:drug therapy* / Q000382:microbiology; D016480:Helicobacter pylori / Q000187:drug effects* / Q000201:enzymology / Q000235:genetics / Q000302:isolation & purification; D006801:Humans; D006863:Hydrogen-Ion Concentration; D064704:Levofloxacin / Q000627:therapeutic use; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D000077266:Moxifloxacin; D017354:Point Mutation; D016896:Treatment Outcome
chemical_list: D000900:Anti-Bacterial Agents; D024841:Fluoroquinolones; D001224:Aspartic Acid; D064704:Levofloxacin; D001216:Asparagine; C560572:finafloxacin; D027081:DNA Gyrase; D000077266:Moxifloxacin