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1.
EuropePMC; 2022.
Preprint in English | EuropePMC | ID: ppcovidwho-335931

ABSTRACT

The ongoing COVID-19 pandemic has claimed more than 6 million lives and continues to test the world economy and healthcare systems. To combat this pandemic, the biological research community has shifted efforts to the development of medical countermeasures, including vaccines and therapeutics. However, to date, the only small molecules approved for the treatment of COVID-19 in the United States are the nucleoside analogue Remdesivir and the protease inhibitor Paxlovid, though multiple compounds have received Emergency Use Authorization and many more are currently being tested in human efficacy trials. One such compound, Apilimod, is being considered as a COVID-19 therapeutic in a Phase II efficacy trial. However, at the time of writing, there are no published efficacy data in human trials or animal COVID-19 models. Here we show that, while Apilimod and other PIKfyve inhibitors have potent antiviral activity in various cell lines against multiple human coronaviruses, these compounds worsen disease in a COVID-19 murine model when given prophylactically or therapeutically.

2.
Gynecol Obstet Invest ; 87(2): 165-172, 2022.
Article in English | MEDLINE | ID: covidwho-1832802

ABSTRACT

INTRODUCTION: Studies indicate a very low rate of SARS-CoV-2 detection in the placenta or occasionally a low rate of vertical transmission in COVID-19 pregnancy. SARS-CoV-2 Delta variant has become a dominant strain over the world and possesses higher infectivity due to mutations in its spike receptor-binding motif. CASE PRESENTATION: To determine whether SARS-CoV-2 Delta variant has increased potential for placenta infection and vertical transmission, we analyzed SARS-CoV-2 infection in the placenta, umbilical cord, and fetal membrane from a case where an unvaccinated mother and her neonate were COVID-19 positive. A 35-year-old primigravida with COVID-19 underwent an emergent cesarean delivery due to placental abruption in the setting of premature rupture of membranes. The neonate tested positive for SARS-CoV-2 within the first 24 h, and then again on days of life 2, 6, 13, and 21. The placenta exhibited intervillositis, increased fibrin deposition, and syncytiotrophoblast necrosis. Sequencing of viral RNA from fixed placental tissue revealed SAR-CoV-2 B.1.167.2 (Delta) variant. Both spike protein and viral RNA were abundantly present in syncytiotrophoblasts, cytotrophoblasts, umbilical cord vascular endothelium, and fetal membranes. CONCLUSION: We report with strong probability the first SARS-CoV-2 Delta variant transplacental transmission. Placental cells exhibited extensive apoptosis, senescence, and ferroptosis after SARS-CoV-2 Delta infection.


Subject(s)
COVID-19 , Pregnancy Complications, Infectious , Adult , COVID-19/diagnosis , Female , Humans , Infant, Newborn , Placenta/blood supply , Pregnancy , Pregnancy Complications, Infectious/diagnosis , RNA, Viral , SARS-CoV-2
3.
EuropePMC; 2022.
Preprint in English | EuropePMC | ID: ppcovidwho-333082

ABSTRACT

Background: In response to the challenge to rapidly identify treatment options for COVID-19, several studies reported that statins, as a drug class, reduce mortality in these patients. Here we explored the possibility that different statins might differ in their ability to exert protective effects based on computational predictions. Methods A Bayesian network tool was used to predict drugs that shift the host transcriptomic response to SARS-CoV-2 infection towards a healthy state. Drugs were predicted using 14 RNA-sequencing datasets from 72 autopsy tissues and 465 COVID-19 patient samples or from cultured human cells and organoids infected with SARS-CoV-2, with a total of 2,436 drugs investigated. Top drug predictions included statins, which were tested in Vero E6 cells infected with SARS-CoV-2 and human endothelial cells infected with a related OC43 coronavirus. A database containing over 4,000 COVID-19 patients on statins was also analyzed to determine mortality risk in patients prescribed specific statins versus untreated matched controls. Findings Simvastatin was among the most highly predicted compounds (14/14 datasets) and five other statins were predicted to be active in > 50% of analyses. In vitro testing of SARS-CoV-2 infected cells revealed simvastatin to be a potent inhibitor whereas most other statins were less effective. Simvastatin also inhibited OC43 infection and reduced cytokine production in endothelial cells. Analysis of the clinical database revealed that reduced mortality risk was only observed in COVID-19 patients prescribed a subset of statins, including simvastatin and atorvastatin. Interpretation Different statins may differ in their ability to sustain the lives of COVID-19 patients despite having a shared target and lipid-modifying mechanism of action. These findings highlight the value of target-agnostic drug prediction coupled with patient databases to identify and validate non-obvious mechanisms and drug repurposing opportunities. Funding DARPA, Wyss Institute, Hess Research Fund, UCSF Program for Breakthrough Biomedical Research, and NIH

4.
EuropePMC;
Preprint in English | EuropePMC | ID: ppcovidwho-327290

ABSTRACT

Major cell entry factors of SARS-CoV-2 are present in neurons;however, the neurotropism of SARS-CoV-2 and the phenotypes of infected neurons are still unclear. Acute neurological disorders occur in many patients, and one-third of COVID-19 survivors suffer from brain diseases. Here, we show that SARS-CoV-2 invades the brains of five patients with COVID-19 and Alzheimers, autism, frontotemporal dementia or no underlying condition by infecting neurons and other cells in the cortex. SARS-CoV-2 induces or enhances Alzheimers-like neuropathology with manifestations of beta-amyloid aggregation and plaque formation, tauopathy, neuroinflammation and cell death. SARS-CoV-2 infects mature but not immature neurons derived from inducible pluripotent stem cells from healthy and Alzheimers individuals through its receptor ACE2 and facilitator neuropilin-1. SARS-CoV-2 triggers Alzheimers-like gene programs in healthy neurons and exacerbates Alzheimers neuropathology. A gene signature defined as an Alzheimers infectious etiology is identified through SARS-CoV-2 infection, and silencing the top three downregulated genes in human primary neurons recapitulates the neurodegenerative phenotypes of SARS-CoV-2. Thus, SARS-CoV-2 invades the brain and activates an Alzheimers-like program.

5.
EuropePMC; 2021.
Preprint in English | EuropePMC | ID: ppcovidwho-296959

ABSTRACT

With much of the world infected with or vaccinated against SARS-CoV-2, understanding the immune responses to the SARS-CoV-2 spike (S) protein in different situations is crucial to controlling the pandemic. We studied the clinical, systemic, mucosal, and cellular responses to two doses of SARS-CoV-2 mRNA vaccines in 62 individuals with and without prior SARS-CoV-2 exposure that were divided into three groups based on serostatus and/or degree of symptoms: Antibody negative, Asymptomatic, and Symptomatic. In the previously SARS-CoV-2-infected (SARS2-infected) Asymptomatic and Symptomatic groups, symptoms related to a recall response were elicited after the first vaccination. Anti-S trimer IgA and IgG levels peaked after 1st vaccination in the SARS2-infected groups, and were higher that the in the SARS2-naive group in the plasma and nasal samples at all time points. Neutralizing antibodies titers were also higher against the WA-1 and B.1.617.2 (Delta) variants of SARS-CoV-2 in the SARS2-infected compared to SARS2-naive vaccinees. After the first vaccination, differences in cellular immunity were not evident between groups, but the AIM+ CD4+ cell response correlated with durability of humoral immunity against the SARS-CoV-2 S protein. In those SARS2-infected, the number of vaccinations needed for protection, the durability, and need for boosters are unknown. However, the lingering differences between the SARS2-infected and SARS2-naive up to 10 months post-vaccination could explain the decreased reinfection rates in the SARS2-infected vaccinees recently reported and suggests that additional strategies (such as boosting of the SARS2-naive vaccinees) are needed to narrow the differences observed between these groups.

6.
Nat Commun ; 12(1): 6055, 2021 10 18.
Article in English | MEDLINE | ID: covidwho-1475294

ABSTRACT

COVID-19 caused by the SARS-CoV-2 virus has become a global pandemic. 3CL protease is a virally encoded protein that is essential across a broad spectrum of coronaviruses with no close human analogs. PF-00835231, a 3CL protease inhibitor, has exhibited potent in vitro antiviral activity against SARS-CoV-2 as a single agent. Here we report, the design and characterization of a phosphate prodrug PF-07304814 to enable the delivery and projected sustained systemic exposure in human of PF-00835231 to inhibit coronavirus family 3CL protease activity with selectivity over human host protease targets. Furthermore, we show that PF-00835231 has additive/synergistic activity in combination with remdesivir. We present the ADME, safety, in vitro, and in vivo antiviral activity data that supports the clinical evaluation of PF-07304814 as a potential COVID-19 treatment.


Subject(s)
COVID-19/drug therapy , Coronavirus 3C Proteases/antagonists & inhibitors , Coronavirus Protease Inhibitors/administration & dosage , Indoles/administration & dosage , Leucine/administration & dosage , Pyrrolidinones/administration & dosage , Adenosine Monophosphate/administration & dosage , Adenosine Monophosphate/adverse effects , Adenosine Monophosphate/analogs & derivatives , Adenosine Monophosphate/pharmacokinetics , Alanine/administration & dosage , Alanine/adverse effects , Alanine/analogs & derivatives , Alanine/pharmacokinetics , Animals , COVID-19/virology , Chlorocebus aethiops , Coronavirus 229E, Human/drug effects , Coronavirus 229E, Human/enzymology , Coronavirus Protease Inhibitors/adverse effects , Coronavirus Protease Inhibitors/pharmacokinetics , Disease Models, Animal , Drug Design , Drug Synergism , Drug Therapy, Combination , HeLa Cells , Humans , Indoles/adverse effects , Indoles/pharmacokinetics , Infusions, Intravenous , Leucine/adverse effects , Leucine/pharmacokinetics , Mice , Pyrrolidinones/adverse effects , Pyrrolidinones/pharmacokinetics , SARS Virus/drug effects , SARS Virus/enzymology , SARS-CoV-2/drug effects , SARS-CoV-2/enzymology , Vero Cells
7.
Nat Microbiol ; 6(10): 1233-1244, 2021 10.
Article in English | MEDLINE | ID: covidwho-1434113

ABSTRACT

Understanding the molecular basis for immune recognition of SARS-CoV-2 spike glycoprotein antigenic sites will inform the development of improved therapeutics. We determined the structures of two human monoclonal antibodies-AZD8895 and AZD1061-which form the basis of the investigational antibody cocktail AZD7442, in complex with the receptor-binding domain (RBD) of SARS-CoV-2 to define the genetic and structural basis of neutralization. AZD8895 forms an 'aromatic cage' at the heavy/light chain interface using germ line-encoded residues in complementarity-determining regions (CDRs) 2 and 3 of the heavy chain and CDRs 1 and 3 of the light chain. These structural features explain why highly similar antibodies (public clonotypes) have been isolated from multiple individuals. AZD1061 has an unusually long LCDR1; the HCDR3 makes interactions with the opposite face of the RBD from that of AZD8895. Using deep mutational scanning and neutralization escape selection experiments, we comprehensively mapped the crucial binding residues of both antibodies and identified positions of concern with regards to virus escape from antibody-mediated neutralization. Both AZD8895 and AZD1061 have strong neutralizing activity against SARS-CoV-2 and variants of concern with antigenic substitutions in the RBD. We conclude that germ line-encoded antibody features enable recognition of the SARS-CoV-2 spike RBD and demonstrate the utility of the cocktail AZD7442 in neutralizing emerging variant viruses.


Subject(s)
Antibodies, Neutralizing/chemistry , Antibodies, Neutralizing/genetics , SARS-CoV-2/immunology , Antibodies, Monoclonal/chemistry , Antibodies, Monoclonal/genetics , Antibodies, Monoclonal/immunology , Antibodies, Neutralizing/immunology , Antibodies, Viral/chemistry , Antibodies, Viral/genetics , Antibodies, Viral/immunology , Antigenic Variation , Binding Sites , COVID-19/immunology , COVID-19/virology , Complementarity Determining Regions/chemistry , Complementarity Determining Regions/genetics , Humans , Mutation , Protein Domains , Spike Glycoprotein, Coronavirus/chemistry , Spike Glycoprotein, Coronavirus/genetics , Spike Glycoprotein, Coronavirus/immunology
8.
Res Sq ; 2021 Feb 15.
Article in English | MEDLINE | ID: covidwho-1417405

ABSTRACT

Recently approved vaccines have already shown remarkable protection in limiting SARS-CoV-2 associated disease. However, immunologic mechanism(s) of protection, as well as how boosting alters immunity to wildtype and newly emerging strains, remain incompletely understood. Here we deeply profiled the humoral immune response in a cohort of non-human primates immunized with a stable recombinant full-length SARS-CoV-2 spike (S) glycoprotein (NVX-CoV2373) at two dose levels, administered as a single or two-dose regimen with a saponin-based adjuvant Matrix-M™. While antigen dose had some effect on Fc-effector profiles, both antigen dose and boosting significantly altered overall titers, neutralization and Fc-effector profiles, driving unique vaccine-induced antibody fingerprints. Combined differences in antibody effector functions and neutralization were strongly associated with distinct levels of protection in the upper and lower respiratory tract, pointing to the presence of combined, but distinct, compartment-specific neutralization and Fc-mechanisms as key determinants of protective immunity against infection. Moreover, NVX-CoV2373 elicited antibodies functionally target emerging SARS-CoV-2 variants, collectively pointing to the critical collaborative role for Fab and Fc in driving maximal protection against SARS-CoV-2. Collectively, the data presented here suggest that a single dose may prevent disease, but that two doses may be essential to block further transmission of SARS-CoV-2 and emerging variants.

9.
Cell Rep Med ; 2(9): 100405, 2021 09 21.
Article in English | MEDLINE | ID: covidwho-1377862

ABSTRACT

Recently approved vaccines have shown remarkable efficacy in limiting SARS-CoV-2-associated disease. However, with the variety of vaccines, immunization strategies, and waning antibody titers, defining the correlates of immunity across a spectrum of antibody titers is urgently required. Thus, we profiled the humoral immune response in a cohort of non-human primates immunized with a recombinant SARS-CoV-2 spike glycoprotein (NVX-CoV2373) at two doses, administered as a single- or two-dose regimen. Both antigen dose and boosting significantly altered neutralization titers and Fc-effector profiles, driving unique vaccine-induced antibody fingerprints. Combined differences in antibody effector functions and neutralization were associated with distinct levels of protection in the upper and lower respiratory tract. Moreover, NVX-CoV2373 elicited antibodies that functionally targeted emerging SARS-CoV-2 variants. Collectively, the data presented here suggest that a single dose may prevent disease via combined Fc/Fab functions but that two doses may be essential to block further transmission of SARS-CoV-2 and emerging variants.


Subject(s)
COVID-19 Vaccines/immunology , SARS-CoV-2/immunology , Saponins/immunology , Animals , Antibodies, Neutralizing/drug effects , Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , COVID-19/immunology , COVID-19/virology , Dose-Response Relationship, Immunologic , Female , Immunity, Humoral/immunology , Immunogenicity, Vaccine , Immunoglobulin Fab Fragments/immunology , Immunoglobulin Fc Fragments/immunology , Macaca mulatta , Male , Nanoparticles , Primates/immunology , SARS-CoV-2/pathogenicity , Spike Glycoprotein, Coronavirus , Vaccination
10.
Nat Biomed Eng ; 5(8): 815-829, 2021 08.
Article in English | MEDLINE | ID: covidwho-1213929

ABSTRACT

The rapid repurposing of antivirals is particularly pressing during pandemics. However, rapid assays for assessing candidate drugs typically involve in vitro screens and cell lines that do not recapitulate human physiology at the tissue and organ levels. Here we show that a microfluidic bronchial-airway-on-a-chip lined by highly differentiated human bronchial-airway epithelium and pulmonary endothelium can model viral infection, strain-dependent virulence, cytokine production and the recruitment of circulating immune cells. In airway chips infected with influenza A, the co-administration of nafamostat with oseltamivir doubled the treatment-time window for oseltamivir. In chips infected with pseudotyped severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), clinically relevant doses of the antimalarial drug amodiaquine inhibited infection but clinical doses of hydroxychloroquine and other antiviral drugs that inhibit the entry of pseudotyped SARS-CoV-2 in cell lines under static conditions did not. We also show that amodiaquine showed substantial prophylactic and therapeutic activities in hamsters challenged with native SARS-CoV-2. The human airway-on-a-chip may accelerate the identification of therapeutics and prophylactics with repurposing potential.


Subject(s)
Antiviral Agents/pharmacology , Antiviral Agents/therapeutic use , COVID-19 Testing/methods , COVID-19/drug therapy , Lab-On-A-Chip Devices , Animals , COVID-19/diagnosis , COVID-19/virology , Cell Line , Cricetinae , Female , Green Fluorescent Proteins , Humans , Male , SARS-CoV-2/drug effects , Virus Internalization/drug effects
12.
ACS Omega ; 6(11): 7454-7468, 2021 Mar 23.
Article in English | MEDLINE | ID: covidwho-1155692

ABSTRACT

Severe acute respiratory coronavirus 2 (SARS-CoV-2) is a newly identified virus that has resulted in over 2.5 million deaths globally and over 116 million cases globally in March, 2021. Small-molecule inhibitors that reverse disease severity have proven difficult to discover. One of the key approaches that has been widely applied in an effort to speed up the translation of drugs is drug repurposing. A few drugs have shown in vitro activity against Ebola viruses and demonstrated activity against SARS-CoV-2 in vivo. Most notably, the RNA polymerase targeting remdesivir demonstrated activity in vitro and efficacy in the early stage of the disease in humans. Testing other small-molecule drugs that are active against Ebola viruses (EBOVs) would appear a reasonable strategy to evaluate their potential for SARS-CoV-2. We have previously repurposed pyronaridine, tilorone, and quinacrine (from malaria, influenza, and antiprotozoal uses, respectively) as inhibitors of Ebola and Marburg viruses in vitro in HeLa cells and mouse-adapted EBOV in mice in vivo. We have now tested these three drugs in various cell lines (VeroE6, Vero76, Caco-2, Calu-3, A549-ACE2, HUH-7, and monocytes) infected with SARS-CoV-2 as well as other viruses (including MHV and HCoV 229E). The compilation of these results indicated considerable variability in antiviral activity observed across cell lines. We found that tilorone and pyronaridine inhibited the virus replication in A549-ACE2 cells with IC50 values of 180 nM and IC50 198 nM, respectively. We used microscale thermophoresis to test the binding of these molecules to the spike protein, and tilorone and pyronaridine bind to the spike receptor binding domain protein with K d values of 339 and 647 nM, respectively. Human Cmax for pyronaridine and quinacrine is greater than the IC50 observed in A549-ACE2 cells. We also provide novel insights into the mechanism of these compounds which is likely lysosomotropic.

13.
Nat Commun ; 12(1): 372, 2021 01 14.
Article in English | MEDLINE | ID: covidwho-1033459

ABSTRACT

The COVID-19 pandemic continues to spread throughout the world with an urgent need for a safe and protective vaccine to effectuate herd protection and control the spread of SARS-CoV-2. Here, we report the development of a SARS-CoV-2 subunit vaccine (NVX-CoV2373) from the full-length spike (S) protein that is stable in the prefusion conformation. NVX-CoV2373 S form 27.2-nm nanoparticles that are thermostable and bind with high affinity to the human angiotensin-converting enzyme 2 (hACE2) receptor. In mice, low-dose NVX-CoV2373 with saponin-based Matrix-M adjuvant elicit high titer anti-S IgG that blocks hACE2 receptor binding, neutralize virus, and protects against SARS-CoV-2 challenge with no evidence of vaccine-associated enhanced respiratory disease. NVX-CoV2373 also elicits multifunctional CD4+ and CD8+ T cells, CD4+ follicular helper T cells (Tfh), and antigen-specific germinal center (GC) B cells in the spleen. In baboons, low-dose levels of NVX-CoV2373 with Matrix-M was also highly immunogenic and elicited high titer anti-S antibodies and functional antibodies that block S-protein binding to hACE2 and neutralize virus infection and antigen-specific T cells. These results support the ongoing phase 1/2 clinical evaluation of the safety and immunogenicity of NVX-CoV2373 with Matrix-M (NCT04368988).


Subject(s)
COVID-19 Vaccines/immunology , COVID-19/prevention & control , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/immunology , Angiotensin-Converting Enzyme 2/genetics , Angiotensin-Converting Enzyme 2/immunology , Animals , Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , COVID-19/genetics , COVID-19/immunology , COVID-19/virology , COVID-19 Vaccines/administration & dosage , COVID-19 Vaccines/genetics , Disease Models, Animal , Female , Male , Mice , Mice, Inbred BALB C , Papio , SARS-CoV-2/genetics , Spike Glycoprotein, Coronavirus/administration & dosage , Spike Glycoprotein, Coronavirus/genetics , T-Lymphocytes/immunology , Vaccines, Subunit/administration & dosage , Vaccines, Subunit/genetics , Vaccines, Subunit/immunology
14.
Proc Natl Acad Sci U S A ; 117(48): 30687-30698, 2020 12 01.
Article in English | MEDLINE | ID: covidwho-922313

ABSTRACT

The SARS-CoV-2 pandemic has made it clear that we have a desperate need for antivirals. We present work that the mammalian SKI complex is a broad-spectrum, host-directed, antiviral drug target. Yeast suppressor screening was utilized to find a functional genetic interaction between proteins from influenza A virus (IAV) and Middle East respiratory syndrome coronavirus (MERS-CoV) with eukaryotic proteins that may be potential host factors involved in replication. This screening identified the SKI complex as a potential host factor for both viruses. In mammalian systems siRNA-mediated knockdown of SKI genes inhibited replication of IAV and MERS-CoV. In silico modeling and database screening identified a binding pocket on the SKI complex and compounds predicted to bind. Experimental assays of those compounds identified three chemical structures that were antiviral against IAV and MERS-CoV along with the filoviruses Ebola and Marburg and two further coronaviruses, SARS-CoV and SARS-CoV-2. The mechanism of antiviral activity is through inhibition of viral RNA production. This work defines the mammalian SKI complex as a broad-spectrum antiviral drug target and identifies lead compounds for further development.


Subject(s)
Antiviral Agents/pharmacology , Coronavirus/drug effects , Filoviridae/drug effects , Host-Pathogen Interactions/drug effects , Multiprotein Complexes/metabolism , Orthomyxoviridae/drug effects , Cell Line , Genes, Suppressor , Models, Molecular , Molecular Targeted Therapy , Protein Binding , RNA, Small Interfering/metabolism , RNA, Viral/genetics , RNA, Viral/metabolism , Saccharomyces cerevisiae/genetics , Viral Proteins/metabolism , Virus Replication/drug effects
15.
J Virol ; 94(21)2020 10 14.
Article in English | MEDLINE | ID: covidwho-878910

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged in China at the end of 2019 and has rapidly caused a pandemic, with over 20 million recorded COVID-19 cases in August 2020 (https://covid19.who.int/). There are no FDA-approved antivirals or vaccines for any coronavirus, including SARS-CoV-2. Current treatments for COVID-19 are limited to supportive therapies and off-label use of FDA-approved drugs. Rapid development and human testing of potential antivirals is urgently needed. Numerous drugs are already approved for human use, and subsequently, there is a good understanding of their safety profiles and potential side effects, making them easier to fast-track to clinical studies in COVID-19 patients. Here, we present data on the antiviral activity of 20 FDA-approved drugs against SARS-CoV-2 that also inhibit SARS-CoV and Middle East respiratory syndrome coronavirus (MERS-CoV). We found that 17 of these inhibit SARS-CoV-2 at non-cytotoxic concentrations. We directly followed up seven of these to demonstrate that all are capable of inhibiting infectious SARS-CoV-2 production. Moreover, we evaluated two of these, chloroquine and chlorpromazine, in vivo using a mouse-adapted SARS-CoV model and found that both drugs protect mice from clinical disease.IMPORTANCE There are no FDA-approved antivirals for any coronavirus, including SARS-CoV-2. Numerous drugs are already approved for human use that may have antiviral activity and therefore could potentially be rapidly repurposed as antivirals. Here, we present data assessing the antiviral activity of 20 FDA-approved drugs against SARS-CoV-2 that also inhibit SARS-CoV and MERS-CoV in vitro We found that 17 of these inhibit SARS-CoV-2, suggesting that they may have pan-anti-coronaviral activity. We directly followed up seven of these and found that they all inhibit infectious-SARS-CoV-2 production. Moreover, we evaluated chloroquine and chlorpromazine in vivo using mouse-adapted SARS-CoV. We found that neither drug inhibited viral replication in the lungs, but both protected against clinical disease.


Subject(s)
Antiviral Agents/pharmacology , Betacoronavirus/drug effects , Coronavirus Infections/drug therapy , Coronavirus Infections/virology , Middle East Respiratory Syndrome Coronavirus/drug effects , Pneumonia, Viral/drug therapy , Pneumonia, Viral/virology , A549 Cells , Animals , COVID-19 , Chloroquine/pharmacology , Chlorpromazine/pharmacology , Drug Approval , Drug Evaluation, Preclinical , Humans , Pandemics , SARS-CoV-2 , Treatment Outcome , United States , United States Food and Drug Administration , Virus Replication/drug effects
16.
N Engl J Med ; 383(24): 2320-2332, 2020 12 10.
Article in English | MEDLINE | ID: covidwho-740054

ABSTRACT

BACKGROUND: NVX-CoV2373 is a recombinant severe acute respiratory syndrome coronavirus 2 (rSARS-CoV-2) nanoparticle vaccine composed of trimeric full-length SARS-CoV-2 spike glycoproteins and Matrix-M1 adjuvant. METHODS: We initiated a randomized, placebo-controlled, phase 1-2 trial to evaluate the safety and immunogenicity of the rSARS-CoV-2 vaccine (in 5-µg and 25-µg doses, with or without Matrix-M1 adjuvant, and with observers unaware of trial-group assignments) in 131 healthy adults. In phase 1, vaccination comprised two intramuscular injections, 21 days apart. The primary outcomes were reactogenicity; laboratory values (serum chemistry and hematology), according to Food and Drug Administration toxicity scoring, to assess safety; and IgG anti-spike protein response (in enzyme-linked immunosorbent assay [ELISA] units). Secondary outcomes included unsolicited adverse events, wild-type virus neutralization (microneutralization assay), and T-cell responses (cytokine staining). IgG and microneutralization assay results were compared with 32 (IgG) and 29 (neutralization) convalescent serum samples from patients with Covid-19, most of whom were symptomatic. We performed a primary analysis at day 35. RESULTS: After randomization, 83 participants were assigned to receive the vaccine with adjuvant and 25 without adjuvant, and 23 participants were assigned to receive placebo. No serious adverse events were noted. Reactogenicity was absent or mild in the majority of participants, more common with adjuvant, and of short duration (mean, ≤2 days). One participant had mild fever that lasted 1 day. Unsolicited adverse events were mild in most participants; there were no severe adverse events. The addition of adjuvant resulted in enhanced immune responses, was antigen dose-sparing, and induced a T helper 1 (Th1) response. The two-dose 5-µg adjuvanted regimen induced geometric mean anti-spike IgG (63,160 ELISA units) and neutralization (3906) responses that exceeded geometric mean responses in convalescent serum from mostly symptomatic Covid-19 patients (8344 and 983, respectively). CONCLUSIONS: At 35 days, NVX-CoV2373 appeared to be safe, and it elicited immune responses that exceeded levels in Covid-19 convalescent serum. The Matrix-M1 adjuvant induced CD4+ T-cell responses that were biased toward a Th1 phenotype. (Funded by the Coalition for Epidemic Preparedness Innovations; ClinicalTrials.gov number, NCT04368988).


Subject(s)
COVID-19 Vaccines/immunology , COVID-19/prevention & control , Spike Glycoprotein, Coronavirus/immunology , Adjuvants, Immunologic/administration & dosage , Adolescent , Adult , Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , COVID-19 Vaccines/adverse effects , Enzyme-Linked Immunosorbent Assay , Female , Humans , Immunization Schedule , Immunogenicity, Vaccine , Immunoglobulin G/immunology , Male , Middle Aged , Nanoparticles , Pandemics , Saponins , Th1 Cells/immunology , Vaccines, Synthetic/adverse effects , Vaccines, Synthetic/immunology , Young Adult
17.
Science ; 369(6506): 1010-1014, 2020 08 21.
Article in English | MEDLINE | ID: covidwho-599036

ABSTRACT

Neutralizing antibodies have become an important tool in treating infectious diseases. Recently, two separate approaches yielded successful antibody treatments for Ebola-one from genetically humanized mice and the other from a human survivor. Here, we describe parallel efforts using both humanized mice and convalescent patients to generate antibodies against the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein, which yielded a large collection of fully human antibodies that were characterized for binding, neutralization, and three-dimensional structure. On the basis of these criteria, we selected pairs of highly potent individual antibodies that simultaneously bind the receptor binding domain of the spike protein, thereby providing ideal partners for a therapeutic antibody cocktail that aims to decrease the potential for virus escape mutants that might arise in response to selective pressure from a single-antibody treatment.


Subject(s)
Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , Betacoronavirus/immunology , Coronavirus Infections/immunology , Pneumonia, Viral/immunology , Spike Glycoprotein, Coronavirus/immunology , Adolescent , Adult , Angiotensin-Converting Enzyme 2 , Animals , Antibodies, Neutralizing/chemistry , Antibodies, Viral/chemistry , Antibody Affinity , Antibody-Dependent Cell Cytotoxicity , Betacoronavirus/chemistry , Binding Sites, Antibody , Broadly Neutralizing Antibodies/chemistry , Broadly Neutralizing Antibodies/immunology , COVID-19 , Cell Line , Coronavirus Infections/therapy , Cytophagocytosis , Epitopes , Humans , Immunization, Passive , Mice , Middle Aged , Models, Molecular , Neutralization Tests , Pandemics , Peptidyl-Dipeptidase A/metabolism , Protein Interaction Domains and Motifs , Receptors, Coronavirus , Receptors, Virus/metabolism , SARS Virus/immunology , SARS-CoV-2 , Spike Glycoprotein, Coronavirus/chemistry , Spike Glycoprotein, Coronavirus/metabolism , Young Adult
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