AUTHOR=Wu Shi , Zheng Yonggui , Guo Yan , Yin Dandan , Zhu Demei , Hu Fupin 

TITLE=In vitro Activity of Lefamulin Against the Common Respiratory Pathogens Isolated From Mainland China During 2017–2019

JOURNAL=Frontiers in Microbiology

VOLUME=11

YEAR=2020

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2020.578824

DOI=10.3389/fmicb.2020.578824

ISSN=1664-302X

ABSTRACT=<sec><title>Purpose</title><p>Lefamulin is a novel antibiotic approved by the U.S. Food and Drug Administration in 2019 for the treatment of community-acquired bacterial pneumonia (CABP). In this study we evaluated the <italic>in vitro</italic> antimicrobial activity of lefamulin in order to better understand its antibiogram.</p></sec><sec><title>Methods</title><p>The test strains were isolated from patients across China during the period from 2017 to 2019, including 634 strains of respiratory pathogens. The minimum inhibitory concentrations (MICs) of lefamulin and comparators were determined by broth microdilution method.</p></sec><sec><title>Results</title><p>Lefamulin showed potent activity against <italic>Streptococcus pneumoniae</italic> and <italic>Staphylococcus</italic> evidenced by 100% inhibition at 0.25 mg/L, and favorable MIC<sub>50/90</sub> (0.125/0.125 mg/L) against <italic>S. pneumoniae</italic> (penicillin MIC ≥ 2 mg/L), MIC<sub>50/90</sub> (≤0.015/0.125 mg/L) against methicillin-resistant <italic>S. aureus</italic>, and MIC<sub>50/90</sub> (≤0.015/0.06 mg/L) against methicillin-resistant <italic>S. epidermidis</italic>. Lefamulin also had good activity against <italic>Streptococcus pyogenes</italic> and <italic>Streptococcus agalactia</italic> (MIC<sub>50/90</sub>: ≤0.015/≤0.015 mg/L), β-lactamase-producing <italic>Haemophilus influenzae</italic> (MIC<sub>50/90</sub>: 0.5/1 mg/L), β-lactamase-negative <italic>H. influenzae</italic> (MIC<sub>50/90</sub>: 1/1 mg/L), <italic>Moraxella catarrhalis</italic> (MIC<sub>50/90</sub>: 0.25/0.25 mg/L), and <italic>Mycoplasma pneumoniae</italic> (MIC<sub>50/90</sub>: 0.03/0.03 mg/L) regardless of resistance to azithromycin. Lefamulin was generally more active than the comparators against the test strains.</p></sec><sec><title>Conclusion</title><p>In summary, lefamulin has good and broad-spectrum coverage of respiratory pathogens (methicillin-sensitive and -resistant <italic>Staphylococcus</italic>, <italic>S. pneumoniae</italic>, β-hemolytic <italic>Streptococcus</italic>, <italic>H. influenzae</italic>, <italic>M. catarrhalis</italic> and <italic>M. pneumoniae</italic>). <italic>In vitro</italic> activity supports the use of lefamulin in the treatment of CABP in China.</p></sec>