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4.
J Transl Med ; 18(1): 405, 2020 10 21.
Article in English | MEDLINE | ID: covidwho-1477432

ABSTRACT

BACKGROUND: Tocilizumab blocks pro-inflammatory activity of interleukin-6 (IL-6), involved in pathogenesis of pneumonia the most frequent cause of death in COVID-19 patients. METHODS: A multicenter, single-arm, hypothesis-driven trial was planned, according to a phase 2 design, to study the effect of tocilizumab on lethality rates at 14 and 30 days (co-primary endpoints, a priori expected rates being 20 and 35%, respectively). A further prospective cohort of patients, consecutively enrolled after the first cohort was accomplished, was used as a secondary validation dataset. The two cohorts were evaluated jointly in an exploratory multivariable logistic regression model to assess prognostic variables on survival. RESULTS: In the primary intention-to-treat (ITT) phase 2 population, 180/301 (59.8%) subjects received tocilizumab, and 67 deaths were observed overall. Lethality rates were equal to 18.4% (97.5% CI: 13.6-24.0, P = 0.52) and 22.4% (97.5% CI: 17.2-28.3, P < 0.001) at 14 and 30 days, respectively. Lethality rates were lower in the validation dataset, that included 920 patients. No signal of specific drug toxicity was reported. In the exploratory multivariable logistic regression analysis, older age and lower PaO2/FiO2 ratio negatively affected survival, while the concurrent use of steroids was associated with greater survival. A statistically significant interaction was found between tocilizumab and respiratory support, suggesting that tocilizumab might be more effective in patients not requiring mechanical respiratory support at baseline. CONCLUSIONS: Tocilizumab reduced lethality rate at 30 days compared with null hypothesis, without significant toxicity. Possibly, this effect could be limited to patients not requiring mechanical respiratory support at baseline. Registration EudraCT (2020-001110-38); clinicaltrials.gov (NCT04317092).


Subject(s)
Antibodies, Monoclonal, Humanized/therapeutic use , Betacoronavirus/drug effects , Coronavirus Infections/drug therapy , Pneumonia, Viral/drug therapy , Adult , Aged , Aged, 80 and over , Betacoronavirus/immunology , COVID-19 , Cohort Studies , Coronavirus Infections/epidemiology , Female , Humans , Italy/epidemiology , Male , Middle Aged , Mortality , Off-Label Use , Pandemics , Pneumonia, Viral/epidemiology , SARS-CoV-2 , Treatment Outcome , Validation Studies as Topic
6.
JAMA ; 323(16): 1582-1589, 2020 04 28.
Article in English | MEDLINE | ID: covidwho-1453469

ABSTRACT

Importance: Coronavirus disease 2019 (COVID-19) is a pandemic with no specific therapeutic agents and substantial mortality. It is critical to find new treatments. Objective: To determine whether convalescent plasma transfusion may be beneficial in the treatment of critically ill patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Design, Setting, and Participants: Case series of 5 critically ill patients with laboratory-confirmed COVID-19 and acute respiratory distress syndrome (ARDS) who met the following criteria: severe pneumonia with rapid progression and continuously high viral load despite antiviral treatment; Pao2/Fio2 <300; and mechanical ventilation. All 5 were treated with convalescent plasma transfusion. The study was conducted at the infectious disease department, Shenzhen Third People's Hospital in Shenzhen, China, from January 20, 2020, to March 25, 2020; final date of follow-up was March 25, 2020. Clinical outcomes were compared before and after convalescent plasma transfusion. Exposures: Patients received transfusion with convalescent plasma with a SARS-CoV-2-specific antibody (IgG) binding titer greater than 1:1000 (end point dilution titer, by enzyme-linked immunosorbent assay [ELISA]) and a neutralization titer greater than 40 (end point dilution titer) that had been obtained from 5 patients who recovered from COVID-19. Convalescent plasma was administered between 10 and 22 days after admission. Main Outcomes and Measures: Changes of body temperature, Sequential Organ Failure Assessment (SOFA) score (range 0-24, with higher scores indicating more severe illness), Pao2/Fio2, viral load, serum antibody titer, routine blood biochemical index, ARDS, and ventilatory and extracorporeal membrane oxygenation (ECMO) supports before and after convalescent plasma transfusion. Results: All 5 patients (age range, 36-65 years; 2 women) were receiving mechanical ventilation at the time of treatment and all had received antiviral agents and methylprednisolone. Following plasma transfusion, body temperature normalized within 3 days in 4 of 5 patients, the SOFA score decreased, and Pao2/Fio2 increased within 12 days (range, 172-276 before and 284-366 after). Viral loads also decreased and became negative within 12 days after the transfusion, and SARS-CoV-2-specific ELISA and neutralizing antibody titers increased following the transfusion (range, 40-60 before and 80-320 on day 7). ARDS resolved in 4 patients at 12 days after transfusion, and 3 patients were weaned from mechanical ventilation within 2 weeks of treatment. Of the 5 patients, 3 have been discharged from the hospital (length of stay: 53, 51, and 55 days), and 2 are in stable condition at 37 days after transfusion. Conclusions and Relevance: In this preliminary uncontrolled case series of 5 critically ill patients with COVID-19 and ARDS, administration of convalescent plasma containing neutralizing antibody was followed by improvement in their clinical status. The limited sample size and study design preclude a definitive statement about the potential effectiveness of this treatment, and these observations require evaluation in clinical trials.


Subject(s)
Antibodies, Neutralizing/therapeutic use , Antibodies, Viral/therapeutic use , Betacoronavirus/immunology , Coronavirus Infections/therapy , Pneumonia, Viral/therapy , Respiratory Distress Syndrome/therapy , Adult , Aged , Antibodies, Viral/blood , Antiviral Agents/therapeutic use , Blood Donors , COVID-19 , Coronavirus Infections/drug therapy , Coronavirus Infections/physiopathology , Critical Illness , Female , Glucocorticoids/therapeutic use , Humans , Immunization, Passive , Immunoglobulin G/blood , Immunoglobulin M/blood , Male , Methylprednisolone/therapeutic use , Middle Aged , Organ Dysfunction Scores , Pandemics , Pneumonia, Viral/drug therapy , Pneumonia, Viral/physiopathology , SARS-CoV-2
9.
J Clin Invest ; 130(11): 6151-6157, 2020 11 02.
Article in English | MEDLINE | ID: covidwho-1435146

ABSTRACT

Emerging data indicate that complement and neutrophils contribute to the maladaptive immune response that fuels hyperinflammation and thrombotic microangiopathy, thereby increasing coronavirus 2019 (COVID-19) mortality. Here, we investigated how complement interacts with the platelet/neutrophil extracellular traps (NETs)/thrombin axis, using COVID-19 specimens, cell-based inhibition studies, and NET/human aortic endothelial cell (HAEC) cocultures. Increased plasma levels of NETs, tissue factor (TF) activity, and sC5b-9 were detected in patients. Neutrophils of patients yielded high TF expression and released NETs carrying active TF. Treatment of control neutrophils with COVID-19 platelet-rich plasma generated TF-bearing NETs that induced thrombotic activity of HAECs. Thrombin or NETosis inhibition or C5aR1 blockade attenuated platelet-mediated NET-driven thrombogenicity. COVID-19 serum induced complement activation in vitro, consistent with high complement activity in clinical samples. Complement C3 inhibition with compstatin Cp40 disrupted TF expression in neutrophils. In conclusion, we provide a mechanistic basis for a pivotal role of complement and NETs in COVID-19 immunothrombosis. This study supports strategies against severe acute respiratory syndrome coronavirus 2 that exploit complement or NETosis inhibition.


Subject(s)
Betacoronavirus , Complement Membrane Attack Complex , Coronavirus Infections , Extracellular Traps , Neutrophils , Pandemics , Pneumonia, Viral , Thromboplastin , Thrombosis , Aged , Betacoronavirus/immunology , Betacoronavirus/metabolism , COVID-19 , Complement Activation/drug effects , Complement Membrane Attack Complex/immunology , Complement Membrane Attack Complex/metabolism , Coronavirus Infections/blood , Coronavirus Infections/immunology , Extracellular Traps/immunology , Extracellular Traps/metabolism , Female , Humans , Male , Middle Aged , Neutrophils/immunology , Neutrophils/metabolism , Peptides, Cyclic/pharmacology , Pneumonia, Viral/blood , Pneumonia, Viral/immunology , Receptor, Anaphylatoxin C5a/antagonists & inhibitors , Receptor, Anaphylatoxin C5a/blood , Receptor, Anaphylatoxin C5a/immunology , Respiratory Distress Syndrome/blood , Respiratory Distress Syndrome/immunology , Respiratory Distress Syndrome/virology , SARS-CoV-2 , Thrombin/immunology , Thrombin/metabolism , Thromboplastin/immunology , Thromboplastin/metabolism , Thrombosis/blood , Thrombosis/immunology , Thrombosis/virology
10.
Rev. saúde pública (Online) ; 54: 69, 2020. tab, graf
Article in English | LILACS (Americas) | ID: covidwho-1389803

ABSTRACT

ABSTRACT OBJECTIVE To estimate the seroprevalence of antibodies to SARS-CoV-2 among blood donors in the state of Rio de Janeiro, Brazil. METHODS Data were collected on 2,857 blood donors from April 14 to 27, 2020. This study reports crude prevalence of antibodies to SARS-CoV-2, population weighted prevalence for the state, and prevalence adjusted for test sensitivity and specificity. Logistic regression models were used to establish the correlates of SARS-CoV-2 prevalence. For the analysis, we considered collection period and site, sociodemographic characteristics, and place of residence. RESULTS The proportion of positive tests for SARS-Cov-2, without any adjustment, was 4.0% (95%CI 3.3-4.7%), and the weighted prevalence was 3.8% (95%CI 3.1-4.5%). We found lower estimates after adjusting for test sensitivity and specificity: 3.6% (95%CI 2.7-4.4%) for the non-weighted prevalence, and 3.3% (95%CI 2.6-4.1%) for the weighted prevalence. Collection period was the variable most significantly associated with crude prevalence: the later the period, the higher the prevalence. Regarding sociodemographic characteristics, the younger the blood donor, the higher the prevalence, and the lower the education level, the higher the odds of testing positive for SARS-Cov-2 antibody. We found similar results for weighted prevalence. CONCLUSIONS Our findings comply with some basic premises: the increasing trend over time, as the epidemic curve in the state is still on the rise; and the higher prevalence among both the youngest, for moving around more than older age groups, and the less educated, for encountering more difficulties in following social distancing recommendations. Despite the study limitations, we may infer that Rio de Janeiro is far from reaching the required levels of herd immunity against SARS-CoV-2.


Subject(s)
Humans , Male , Female , Adult , Aged , Young Adult , Pneumonia, Viral/immunology , Blood Donors/statistics & numerical data , Coronavirus Infections/immunology , Betacoronavirus/immunology , Antibodies, Viral/blood , Pneumonia, Viral/blood , Pneumonia, Viral/epidemiology , Brazil/epidemiology , Immunoglobulin G/blood , Immunoglobulin M/blood , Seroepidemiologic Studies , Prevalence , Cross-Sectional Studies , Regression Analysis , Sensitivity and Specificity , Coronavirus Infections/blood , Coronavirus Infections/epidemiology , Pandemics , SARS-CoV-2 , COVID-19 , Middle Aged
12.
Sci Adv ; 6(28): eabb8097, 2020 07.
Article in English | MEDLINE | ID: covidwho-1388430

ABSTRACT

The prevalence of respiratory illness caused by the novel SARS-CoV-2 virus associated with multiple organ failures is spreading rapidly because of its contagious human-to-human transmission and inadequate globalhealth care systems. Pharmaceutical repurposing, an effective drug development technique using existing drugs, could shorten development time and reduce costs compared to those of de novo drug discovery. We carried out virtual screening of antiviral compounds targeting the spike glycoprotein (S), main protease (Mpro), and the SARS-CoV-2 receptor binding domain (RBD)-angiotensin-converting enzyme 2 (ACE2) complex of SARS-CoV-2. PC786, an antiviral polymerase inhibitor, showed enhanced binding affinity to all the targets. Furthermore, the postfusion conformation of the trimeric S protein RBD with ACE2 revealed conformational changes associated with PC786 drug binding. Exploiting immunoinformatics to identify T cell and B cell epitopes could guide future experimental studies with a higher probability of discovering appropriate vaccine candidates with fewer experiments and higher reliability.


Subject(s)
Antiviral Agents/pharmacology , Betacoronavirus/immunology , Coronavirus Infections/prevention & control , Cysteine Endopeptidases/chemistry , Drug Design , Pandemics/prevention & control , Peptidyl-Dipeptidase A/chemistry , Pneumonia, Viral/prevention & control , Spike Glycoprotein, Coronavirus/chemistry , Viral Nonstructural Proteins/chemistry , Angiotensin-Converting Enzyme 2 , Benzamides , Benzazepines , Betacoronavirus/drug effects , Betacoronavirus/metabolism , Binding Sites , COVID-19 , Coronavirus 3C Proteases , Coronavirus Infections/immunology , Coronavirus Infections/virology , Cysteine Endopeptidases/immunology , Cysteine Endopeptidases/metabolism , Drug Evaluation, Preclinical , Epitopes, B-Lymphocyte/drug effects , Epitopes, B-Lymphocyte/immunology , Epitopes, T-Lymphocyte/drug effects , Epitopes, T-Lymphocyte/immunology , Humans , Molecular Docking Simulation , Peptidyl-Dipeptidase A/immunology , Peptidyl-Dipeptidase A/metabolism , Pneumonia, Viral/immunology , Pneumonia, Viral/virology , Protein Binding , Protein Conformation , Protein Domains , Protein Interaction Domains and Motifs , SARS-CoV-2 , Spike Glycoprotein, Coronavirus/immunology , Spike Glycoprotein, Coronavirus/metabolism , Spiro Compounds/pharmacology , Viral Nonstructural Proteins/immunology , Viral Nonstructural Proteins/metabolism
13.
HLA ; 96(3): 277-298, 2020 09.
Article in English | MEDLINE | ID: covidwho-1388402

ABSTRACT

We report detailed peptide-binding affinities between 438 HLA Class I and Class II proteins and complete proteomes of seven pandemic human viruses, including coronaviruses, influenza viruses and HIV-1. We contrast these affinities with HLA allele frequencies across hundreds of human populations worldwide. Statistical modelling shows that peptide-binding affinities classified into four distinct categories depend on the HLA locus but that the type of virus is only a weak predictor, except in the case of HIV-1. Among the strong HLA binders (IC50 ≤ 50), we uncovered 16 alleles (the top ones being A*02:02, B*15:03 and DRB1*01:02) binding more than 1% of peptides derived from all viruses, 9 (top ones including HLA-A*68:01, B*15:25, C*03:02 and DRB1*07:01) binding all viruses except HIV-1, and 15 (top ones A*02:01 and C*14:02) only binding coronaviruses. The frequencies of strongest and weakest HLA peptide binders differ significantly among populations from different geographic regions. In particular, Indigenous peoples of America show both higher frequencies of strongest and lower frequencies of weakest HLA binders. As many HLA proteins are found to be strong binders of peptides derived from distinct viral families, and are hence promiscuous (or generalist), we discuss this result in relation to possible signatures of natural selection on HLA promiscuous alleles due to past pathogenic infections. Our findings are highly relevant for both evolutionary genetics and the development of vaccine therapies. However they should not lead to forget that individual resistance and vulnerability to diseases go beyond the sole HLA allelic affinity and depend on multiple, complex and often unknown biological, environmental and other variables.


Subject(s)
Coronavirus Infections/epidemiology , HIV Infections/epidemiology , HLA Antigens/chemistry , Influenza, Human/epidemiology , Pandemics , Peptides/chemistry , Pneumonia, Viral/epidemiology , Severe Acute Respiratory Syndrome/epidemiology , Viral Proteins/chemistry , Africa/epidemiology , Americas/epidemiology , Amino Acid Sequence , Asia/epidemiology , Australia/epidemiology , Betacoronavirus/genetics , Betacoronavirus/immunology , COVID-19 , Computational Biology , Coronavirus Infections/immunology , Coronavirus Infections/virology , Europe/epidemiology , HIV Infections/immunology , HIV Infections/virology , HIV-1/genetics , HIV-1/immunology , HLA Antigens/classification , HLA Antigens/genetics , HLA Antigens/immunology , Humans , Influenza A Virus, H1N1 Subtype/genetics , Influenza A Virus, H1N1 Subtype/immunology , Influenza A Virus, H3N2 Subtype/genetics , Influenza A Virus, H3N2 Subtype/immunology , Influenza A Virus, H7N9 Subtype/genetics , Influenza A Virus, H7N9 Subtype/immunology , Influenza, Human/immunology , Influenza, Human/virology , Kinetics , Middle East Respiratory Syndrome Coronavirus/genetics , Middle East Respiratory Syndrome Coronavirus/immunology , Peptides/genetics , Peptides/immunology , Pneumonia, Viral/immunology , Pneumonia, Viral/virology , Protein Binding , SARS Virus/genetics , SARS Virus/immunology , SARS-CoV-2 , Severe Acute Respiratory Syndrome/immunology , Severe Acute Respiratory Syndrome/virology , Viral Proteins/genetics , Viral Proteins/immunology
16.
Nature ; 583(7818): 834-838, 2020 07.
Article in English | MEDLINE | ID: covidwho-1387423

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a novel coronavirus with high nucleotide identity to SARS-CoV and to SARS-related coronaviruses that have been detected in horseshoe bats, has spread across the world and had a global effect on healthcare systems and economies1,2. A suitable small animal model is needed to support the development of vaccines and therapies. Here we report the pathogenesis and transmissibility of SARS-CoV-2 in golden (Syrian) hamsters (Mesocricetus auratus). Immunohistochemistry assay demonstrated the presence of viral antigens in nasal mucosa, bronchial epithelial cells and areas of lung consolidation on days 2 and 5 after inoculation with SARS-CoV-2, followed by rapid viral clearance and pneumocyte hyperplasia at 7 days after inoculation. We also found viral antigens in epithelial cells of the duodenum, and detected viral RNA in faeces. Notably, SARS-CoV-2 was transmitted efficiently from inoculated hamsters to naive hamsters by direct contact and via aerosols. Transmission via fomites in soiled cages was not as efficient. Although viral RNA was continuously detected in the nasal washes of inoculated hamsters for 14 days, the communicable period was short and correlated with the detection of infectious virus but not viral RNA. Inoculated and naturally infected hamsters showed apparent weight loss on days 6-7 post-inoculation or post-contact; all hamsters returned to their original weight within 14 days and developed neutralizing antibodies. Our results suggest that features associated with SARS-CoV-2 infection in golden hamsters resemble those found in humans with mild SARS-CoV-2 infections.


Subject(s)
Betacoronavirus/pathogenicity , Coronavirus Infections/transmission , Coronavirus Infections/virology , Disease Models, Animal , Lung/pathology , Lung/virology , Mesocricetus/virology , Pneumonia, Viral/transmission , Pneumonia, Viral/virology , Aerosols , Alveolar Epithelial Cells/pathology , Alveolar Epithelial Cells/virology , Animals , Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , Antigens, Viral/immunology , Antigens, Viral/isolation & purification , Antigens, Viral/metabolism , Betacoronavirus/immunology , Betacoronavirus/isolation & purification , Betacoronavirus/metabolism , Bronchi/pathology , Bronchi/virology , COVID-19 , Coronavirus Infections/immunology , Duodenum/virology , Fomites/virology , Housing, Animal , Kidney/virology , Male , Mesocricetus/immunology , Nasal Mucosa/virology , Pandemics , Pneumonia, Viral/immunology , RNA, Viral/analysis , SARS-CoV-2 , Viral Load , Weight Loss
17.
Nat Commun ; 11(1): 5337, 2020 10 21.
Article in English | MEDLINE | ID: covidwho-1387319

ABSTRACT

The CR3022 antibody, selected from a group of SARS-CoV monoclonal antibodies for its ability to cross-react with SARS-CoV-2, has been examined for its ability to bind to the ectodomain of the SARS-CoV-2 spike glycoprotein. Using cryo-electron microscopy we show that antibody binding requires rearrangements in the S1 domain that result in dissociation of the spike.


Subject(s)
Antibodies, Monoclonal/immunology , Antibodies, Viral/immunology , Betacoronavirus/immunology , Binding Sites, Antibody/immunology , Spike Glycoprotein, Coronavirus/immunology , Animals , COVID-19 , Cell Line , Chlorocebus aethiops , Coronavirus Infections/virology , Cryoelectron Microscopy , Humans , Neutralization Tests , Pandemics , Pneumonia, Viral/virology , Protein Domains/immunology , SARS-CoV-2 , Vero Cells
19.
Signal Transduct Target Ther ; 5(1): 221, 2020 10 06.
Article in English | MEDLINE | ID: covidwho-1387195
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