Search

Background: Favipiravir, an anti-influenza drug, has in vitro antiviral activity against SARS-CoV-2. Clinical trial evidence to date is inconclusive. Favipiravir has been recommended for the treatment of COVID-19 in some countries. Methods: In a multicentre open-label, randomised, controlled, adaptive platform trial, low-risk adult patients with early symptomatic COVID-19 were randomised to one of ten treatment arms including high dose oral favipiravir (3.6g on day 0 followed by 1.6g daily to complete 7 days treatment) or no study drug. The primary outcome assessed in a modified intention-to-treat population (mITT) was the rate of viral clearance (derived under a linear mixed-effects model from the daily log10 viral densities in standardised duplicate oropharyngeal swab eluates taken daily over 8 days [18 swabs per patient]). The safety population included all patients who received at least one dose of the allocated intervention. This ongoing adaptive platform trial is registered at ClinicalTrials.gov (NCT05041907). Results: In the final analysis, the mITT population contained data from 114 patients randomised to favipiravir and 126 patients randomised concurrently to no study drug. Under the linear mixed-effects model fitted to all oropharyngeal viral density estimates in the first 8 days from randomisation (4,318 swabs), there was no difference in the rate of viral clearance between patients administered favipiravir and patients receiving no study drug -1% (95% CI: -14 to 14% change). High dose favipiravir was well tolerated. Interpretation: Favipiravir does not accelerate viral clearance in early symptomatic COVID-19.

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 absentin vitroactivity 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 log10viral densities (days 0-7) in standardized duplicate oropharyngeal swab eluates. This ongoing adaptive trial is registered atClinicalTrials.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 apost hocsubgroup 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 reducedin vitroactivities, casirivimab/imdevimab retainsin vivoantiviral 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.

RationaleExhaled breath condensate (EBC) promises a valuable, non-invasive, and easy to obtain clinical sample. However, it’s not currently used diagnostically due to poor reproducibility, sample contamination, and sample loss.ObjectiveWe evaluated whether a new, hand-held EBC collector (PBM-HALETM) that separates inertially impacted large droplets (LD) before condensing fine aerosols (FA) in distinct, self-sealing containers, overcomes current limitations.MethodsSampling consistency was determined in healthy volunteers by microbial culture, 16S phylogenetics, spectrophotometry, RT-PCR, and HILIC-MS. Capture of aerosolised polystyrene beads, liposomes, virus-like particles, or pseudotyped virus was analysed by nanoparticle tracking analysis, reporter expression assays, and flow cytometry. Acute symptomatic COVID-19 case tidal FA EBC viral load was quantified by RT-qPCR. Exhaled particles were counted by laser light scattering.Measurements and Main ResultsSalivary amylase-free FA EBC capture was linear (R2=0.9992; 0.25-30 min) yielding RNA (6.03 μg/mL) containing eukaryotic 18S rRNA (RT-qPCR; pStreptococcus enrichment in a mild dry cough case. Nebulized pseudotyped virus infectivity loss ConclusionsHigh purity, distal airway FA EBC can reproducibly and robustly inform contamination-free infectious agent emission sources, and be quantitatively assayed for multiple host, microbial, and lifestyle biomarker classes.