Journal of internal medicine
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Adaptive immune responses play critical roles in viral clearance and protection against re-infection, and SARS-CoV-2 is no exception. What is exceptional is the rapid characterization of the immune response to the virus performed by researchers during the first 20 months of the pandemic. This has given us a more detailed understanding of SARS-CoV-2 compared to many viruses that have been with us for a long time. ⋯ The pandemic has engaged scientists and the public alike, and terms such as seroprevalence, neutralizing antibodies, antibody escape and vaccine certificates have become familiar to a broad community. Here, we review key findings concerning B cell and antibody (Ab) responses to SARS-CoV-2, focusing on non-severe cases and anti-spike (S) Ab responses in particular, the latter being central to protective immunity induced by infection or vaccination. The emergence of viral variants that have acquired mutations in S acutely highlights the need for continued characterization of both emerging variants and Ab responses against these during the evolving pathogen-immune system arms race.
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Lefamulin is a novel antibiotic agent within the pleuromutilin derivative class approved for the treatment of community-acquired bacterial pneumonia (CABP) by the United States Food and Drug Administration and the European Commission in 2019 and 2020, respectively. The objective of this article is to provide a summary of clinically relevant data underlying lefamulin and to provide recommendations for its place in therapy. In vitro data establish lefamulin's activity against a number of Gram-positive, Gram-negative and atypical organisms relevant in the treatment of CABP, including Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis, Legionella pneumophila, Mycoplasma pneumoniae and Chlamydophila pneumoniae. ⋯ Pooled and post hoc analyses have confirmed these effects for a variety of subgroups and secondary endpoints. Real-world study data post-approval have largely not yet emerged for lefamulin, and there is a need for further investigation into safety/efficacy for off-label indications such as acute bacterial skin and skin structure infections and sexually transmitted infections. Further data regarding tolerability, particularly with long-term use, as well as the emergence of resistance over time, are still undefined.