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1.
Preprint en Inglés | medRxiv | ID: ppmedrxiv-22281161

RESUMEN

BackgroundUncertainty over the therapeutic benefit provided by parenteral remdesivir in COVID-19 has resulted in varying treatment guidelines. Early in the pandemic the monoclonal antibody cocktail, casirivimab/imdevimab, proved highly effective in clinical trials but because of weak or absent in vitro activity against the SARS-CoV-2 Omicron BA.1 subvariant, it is no longer recommended. MethodsIn a multicenter open label, randomized, controlled adaptive platform trial, low-risk adult patients with early symptomatic COVID-19 were randomized to one of eight treatment arms including intravenous remdesivir (200mg followed by 100mg daily for five days), casirivimab/imdevimab (600mg/600mg), and no study drug. The primary outcome was the viral clearance rate in the modified intention-to-treat population derived from daily log10 viral densities (days 0-7) in standardized duplicate oropharyngeal swab eluates. This ongoing adaptive trial is registered at ClinicalTrials.gov (NCT05041907). ResultsAcceleration in mean estimated SARS-CoV-2 viral clearance, compared with the contemporaneous no study drug arm (n=64), was 42% (95%CI 18 to 73%) for remdesivir (n=67). Acceleration with casirivimab/imdevimab was 58% (95%CI: 10 to 120) in Delta (n=13), and 20% (95%CI: 3 to 43) in Omicron variant (n=61) infections compared with contemporaneous no study drug arm (n=84). In a post hoc subgroup analysis viral clearance was accelerated by 8% in BA.1 (95%CI: -21 to 59) and 23% (95%CI: 3 to 49) in BA.2 and BA.5 Omicron subvariants. ConclusionsParenteral remdesivir accelerates viral clearance in early symptomatic COVID-19. Despite substantially reduced in vitro activities, casirivimab/imdevimab retains in vivo antiviral activity against COVID-19 infections caused by currently prevalent Omicron subvariants. Brief summaryIn early symptomatic COVID-19 remdesivir accelerated viral clearance by 42% while the monoclonal antibody cocktail casirivimab/imdevimab accelerated clearance by approximately 60% in SARS-CoV-2 Delta variant infections, and by approximately 25% in infections with Omicron subvariants BA.2 and BA.5.

2.
Preprint en Inglés | medRxiv | ID: ppmedrxiv-20231217

RESUMEN

Prolonged infection of SARS-CoV-2 represents a challenge to the development of effective public health policies to control the COVID-19 pandemic. The reason why some people have persistent infection and how the virus survives for so long are still not fully understood. For this reason, we aimed to investigate the intra-host evolution of SARS-CoV-2 during persistent infection. Thirty-three patients who remained RT-PCR positive in the nasopharynx for at least 16 days were included in this study. Complete SARS-CoV-2 sequences were obtained for each patient at two time points. Phylogenetic, populational, and computational analysis of viral sequences confirmed persistent infection with evidence for a transmission cluster in health care professionals that shared the same workplace. A high number of missense variants targeting crucial structural and non-structural proteins such as Spike and Helicase was found. Interestingly, longitudinal acquisition of substitutions in Spike protein mapped many SARS-CoV-2 predicted T cell epitopes. Furthermore, the mutational profiles observed were suggestive of RNA editing enzyme activities, indicating innate immune mechanisms of the host cell. Viral quasispecies analysis corroborates persistent infection mainly by increasing richness and nucleotide diversity over time. Altogether, our findings highlight a dynamic and complex landscape of host and pathogen interaction during persistent infection suggesting that the hosts innate immunity shapes the increase of intra-host diversity with possible implications for therapeutic strategies and public health decisions during the COVID-19 pandemic.

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