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1.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-22271064

RESUMO

ObjectivesWe evaluated the clinical, virological and safety outcomes of lopinavir/ritonavir, lopinavir/ritonavir-interferon (IFN)-{beta}-1a, hydroxychloroquine or remdesivir in comparison to standard of care (control) in COVID-19 inpatients requiring oxygen and/or ventilatory support. While preliminary results were previously published, we present here the final results, following completion of the data monitoring. MethodsWe conducted a phase 3 multi-centre open-label, randomized 1:1:1:1:1, adaptive, controlled trial (DisCoVeRy), add-on trial to Solidarity (NCT04315948, EudraCT2020-000936-23). The primary outcome was the clinical status at day 15, measured by the WHO 7-point ordinal scale. Secondary outcomes included SARS-CoV-2 quantification in respiratory specimens, pharmacokinetic and safety analyses. We report the results for the lopinavir/ritonavir-containing arms and for the hydroxychloroquine arm, which were stopped prematurely. ResultsThe intention-to-treat population included 593 participants (lopinavir/ritonavir, n=147; lopinavir/ritonavir-IFN-{beta}-1a, n=147; hydroxychloroquine, n=150; control, n=149), among whom 421 (71.0%) were male, the median age was 64 years (IQR, 54-71) and 214 (36.1%) had a severe disease. The day 15 clinical status was not improved with investigational treatments: lopinavir/ritonavir versus control, adjusted odds ratio (aOR) 0.82, (95% confidence interval [CI] 0.54-1.25, P=0.36); lopinavir/ritonavir-IFN-{beta}-1a versus control, aOR 0.69 (95%CI 0.45-1.05, P=0.08); hydroxychloroquine versus control, aOR 0.94 (95%CI 0.62-1.41, P=0.76). No significant effect of investigational treatment was observed on SARS-CoV-2 clearance. Trough plasma concentrations of lopinavir and ritonavir were higher than those expected, while those of hydroxychloroquine were those expected with the dosing regimen. The occurrence of Serious Adverse Events was significantly higher in participants allocated to the lopinavir/ritonavir-containing arms. ConclusionIn adults hospitalized for COVID-19, lopinavir/ritonavir, lopinavir/ritonavir-IFN-{beta}-1a and hydroxychloroquine did not improve the clinical status at day 15, nor SARS-CoV-2 clearance in respiratory tract specimens.

2.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-20249038

RESUMO

BackgroundThe systemic antibody responses to SARS-CoV-2 in COVID-19 patients has been extensively studied. However, much less is known about the mucosal responses in the upper airways at the site of initial SARS-CoV-2 replication. Local antibody responses in the nasopharyngeal epithelium, that are likely to determine the course of infection, have not been analysed so far nor their correlation with antibody responses in serum. MethodsThe IgG and IgA antibody responses were analysed in the plasma as well as in nasopharyngeal swabs (NPS) from the first four COVID-19 patients confirmed by RT-qPCR in France. Two were pauci-symptomatic while two developed severe disease. Taking advantage of a comprehensive series of plasma and nasopharyngeal samples, we characterized their antibody profiles from the second week post symptoms onset, by using an in-house ELISA to detect anti-SARS-CoV-2 Nucleoprotein (N) IgG and IgA. ResultsAnti-N IgG and IgA antibodies were detected in the NPS of severe patients. Overall, the levels of IgA and IgG antibodies in plasma and NPS appeared specific to each patient. ConclusionsAnti-N IgG and IgA antibodies are detected in NPS, and their levels are related to antibody levels in plasma. The two patients with severe disease exhibited different antibody profiles that may reflect different disease outcome. For the pauci-symptomatic patients, one showed a low anti-N IgG and IgA response in the plasma only, while the other one did not exhibit overt serological response.

3.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-20248149

RESUMO

BackgroundLopinavir/ritonavir, lopinavir/ritonavir-interferon (IFN)-{beta}-1a and hydroxychloroquine efficacy for COVID-19 have been evaluated, but detailed evaluation is lacking. ObjectiveTo determine the efficacy of lopinavir/ritonavir, lopinavir/ritonavir-IFN-{beta}-1a, hydroxychloroquine or remdesivir for improving the clinical, virological outcomes in COVID-19 inpatients. DesignOpen-label, randomized, adaptive, controlled trial. SettingMulti-center trial with patients from France. Participants583 COVID-19 inpatients requiring oxygen and/or ventilatory support InterventionStandard of care (SoC, control), SoC plus lopinavir/ritonavir (400 mg lopinavir and 100 mg ritonavir every 12h for 14 days), SoC plus lopinavir/ritonavir plus IFN-{beta}-1a (44 g of subcutaneous IFN-{beta}-1a on days 1, 3, and 6), SoC plus hydroxychloroquine (400 mg twice on day 1 then 400 mg once daily for 9 days) or SoC plus remdesivir (200 mg intravenously on day 1 then 100 mg once-daily for hospitalization duration or 10 days). MeasurementsThe primary outcome was the clinical status at day 15, measured by the WHO 7-point ordinal scale. Secondary outcomes included SARS-CoV-2 quantification in respiratory specimens and safety analyses. ResultsAdjusted Odds Ratio (aOR) for the WHO 7-point ordinal scale were not in favor of investigational treatments: lopinavir/ritonavir versus control, aOR 0.83, 95%CI, 0.55 to 1.26, P=0.39; lopinavir/ritonavir-IFN-{beta}-1a versus control, aOR 0.69, 95%CI, 0.45 to 1.04, P=0.08; hydroxychloroquine versus control, aOR 0.93, 95%CI, 0.62 to 1.41, P=0.75. No significant effect on SARS-CoV-2 RNA clearance in respiratory tract was evidenced. Lopinavir/ritonavir-containing treatments were significantly associated with more SAE. LimitationsNot a placebo-controlled, no anti-inflammatory agents tested. ConclusionNo improvement of the clinical status at day 15 nor SARS-CoV-2 RNA clearance in respiratory tract specimens by studied drugs. This comforts the recent Solidarity findings. RegistrationNCT04315948. FundingPHRC 2020, Dim OneHealth, REACTing

4.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-20246934

RESUMO

COVID-19 SARS-CoV-2 infection exhibits wide inter-individual clinical variability, from silent infection to severe disease and death. The identification of high-risk patients is a continuing challenge in routine care. We aimed to identify factors that influence clinical worsening. We analyzed 52 cell populations, 71 analytes, and RNA-seq gene expression in the blood of severe patients from the French COVID cohort upon hospitalization (n = 61). COVID-19 patients showed severe abnormalities of 27 cell populations relative to healthy donors (HDs). Forty-two cytokines, neutrophil chemo-attractants, and inflammatory components were elevated in COVID-19 patients. Supervised gene expression analyses showed differential expression of genes for neutrophil activation, interferon signaling, T- and B-cell receptors, EIF2 signaling, and ICOS-ICOSL pathways in COVID-19 patients. Unsupervised analysis confirmed the prominent role of neutrophil activation, with a high abundance of CD177, a specific neutrophil activation marker. CD177 was the most highly differentially-expressed gene contributing to the clustering of severe patients and its abundance correlated with CD177 protein serum levels. CD177 levels were higher in COVID-19 patients from both the French and "confirmatory" Swiss cohort (n = 203) than in HDs (P< 0.01) and in ICU than non-ICU patients (P< 0.001), correlating with the time to symptoms onset (P = 0.002). Longitudinal measurements showed sustained levels of serum CD177 to discriminate between patients with the worst prognosis, leading to death, and those who recovered (P = 0.01). These results highlight neutrophil activation as a hallmark of severe disease and CD177 assessment as a reliable prognostic marker for routine care.

5.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-20247551

RESUMO

The COVID-19 pandemic has generated many concerns about cross-contamination risks, particularly in hospital settings and Intensive Care Units (ICU). Virus-laden aerosols produced by infected patients can propagate throughout ventilated rooms and put medical personnel entering them at risk. Experimental results found with a schlieren optical method have shown that the air flows generated by a cough and normal breathing were modified by the oxygenation technique used, especially when using High Flow Nasal Canulae, increasing the shedding of potentially infectious airborne particles. This study also uses a 3D Computational Fluid Dynamics model based on a Lattice Boltzmann Method to simulate the air flows as well as the movement of numerous airborne particles produced by a patients cough within an ICU room under negative pressure. The effects of different mitigation scenarii on the amount of aerosols potentially containing SARS-CoV-2 that are extracted through the ventilation system are investigated. Numerical results indicate that adequate bed orientation and additional air treatment unit positioning can increase by 40% the number of particles extracted and decrease by 25% the amount of particles deposited on surfaces 45s after shedding. This approach could help lay the grounds for a more comprehensive way to tackle contamination risks in hospitals, as the model can be seen as a proof of concept and be adapted to any room configuration.

6.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-20191759

RESUMO

Background. Molecular assays on nasopharyngeal swabs remain the cornerstone of COVID-19 diagnostic. Despite massive worldwide efforts, the high technicalities of nasopharyngeal sampling and molecular assays, as well as scarce resources of reagents, limit our testing capabilities. Several strategies failed, to date, to fully alleviate this testing process (e.g. saliva sampling or antigen testing on nasopharyngeal samples). We assessed the performances of a new ELISA microplate assay quantifying SARS-CoV-2 nucleocapsid antigen (N-antigen) in serum or plasma. Methods. The specificity of the assay, determined on 63 non-COVID patients, was 98.4% (95% confidence interval [CI], 85.3 to 100). Performances were determined on 227 serum samples from 165 patients with RT-PCR confirmed SARS-CoV-2 infection included in the French COVID and CoV-CONTACT cohorts. Findings. Sensitivity was 132/142, 93.0% (95% CI, 84.7 to 100), within the first two weeks after symptoms onset. A subset of 73 COVID-19 patients had a serum collected within 24 hours following or preceding a positive nasopharyngeal swab. Among patients with high nasopharyngeal viral loads, Ct value below 30 and 33, only 1/50 and 4/67 tested negative for N-antigenemia, respectively. Among patients with a negative nasopharyngeal RT-PCR, 8/12 presented positive N-antigenemia. The lower respiratory tract was explored for 6/8 patients, showing positive PCR in 5 cases. Interpretation. This is the first demonstration of the N-antigen antigenemia during COVID-19. Its detection presented a robust sensitivity, especially within the first 14 days after symptoms onset and high nasopharyngeal viral loads. These findings have to be confirmed with higher representation of outpatients. This approach could provide a valuable new option for COVID-19 diagnosis, only requiring a blood draw and easily scalable in all clinical laboratories.

7.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-20087239

RESUMO

We report a longitudinal analysis of the immune response associated with a fatal case of COVID-19. This patient exhibited a rapid evolution towards multiorgan failure. SARS-CoV-2 was detected in multiple nasopharyngeal, blood, and pleural samples, despite antiviral and immunomodulator treatment. Clinical evolution in the blood was marked by an increase (2-3 fold) in differentiated effector T cells expressing exhaustion (PD-1) and senescence (CD57) markers, an expansion of antibody-secreting cells, a 15-fold increase in {gamma}{delta} T-cell and proliferating NK-cell populations, and the total disappearance of monocytes, suggesting lung trafficking. In the serum, waves of a proinflammatory cytokine storm, Th1 and Th2 activation, and markers of T-cell exhaustion, apoptosis, cell cytotoxicity, and endothelial activation were observed until the fatal outcome. This case underscores the need for well-designed studies to investigate complementary approaches to control viral replication, the source of the hyperinflammatory status, and immunomodulation to target the pathophysiological response.

8.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-20068858

RESUMO

It is of paramount importance to evaluate the prevalence of both asymptomatic and symptomatic cases of SARS-CoV-2 infection and their antibody response profile. Here, we performed a pilot study to assess the levels of anti-SARS-CoV-2 antibodies in samples taken from 491 pre-epidemic individuals, 51 patients from Hopital Bichat (Paris), 209 pauci-symptomatic individuals in the French Oise region and 200 contemporary Oise blood donors. Two in-house ELISA assays, that recognize the full-length nucleoprotein (N) or trimeric Spike (S) ectodomain were implemented. We also developed two novel assays: the S-Flow assay, which is based on the recognition of S at the cell surface by flow-cytometry, and the LIPS assay that recognizes diverse antigens (including S1 or N C-terminal domain) by immunoprecipitation. Overall, the results obtained with the four assays were similar, with differences in sensitivity that can be attributed to the technique and the antigen in use. High antibody titers were associated with neutralisation activity, assessed using infectious SARS-CoV-2 or lentiviral-S pseudotypes. In hospitalized patients, seroconversion and neutralisation occurred on 5-14 days post symptom onset, confirming previous studies. Seropositivity was detected in 29% of pauci-symptomatic individuals within 15 days post-symptoms and 3 % of blood of healthy donors collected in the area of a cluster of COVID cases. Altogether, our assays allow for a broad evaluation of SARS-CoV2 seroprevalence and antibody profiling in different population subsets.

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