RESUMO
Effective treatments against Severe Acute Respiratory Syndrome coronavirus 2 (SARS-CoV-2) are urgently needed. Monoclonal antibodies have shown promising results in patients. Here, we evaluate the in vivo prophylactic and therapeutic effect of COVA1-18, a neutralizing antibody highly potent against the B.1.1.7 isolate. In both prophylactic and therapeutic settings, SARS-CoV-2 remains undetectable in the lungs of treated hACE2 mice. Therapeutic treatment also causes a reduction in viral loads in the lungs of Syrian hamsters. When administered at 10 mg kg-1 one day prior to a high dose SARS-CoV-2 challenge in cynomolgus macaques, COVA1-18 shows very strong antiviral activity in the upper respiratory compartments. Using a mathematical model, we estimate that COVA1-18 reduces viral infectivity by more than 95% in these compartments, preventing lymphopenia and extensive lung lesions. Our findings demonstrate that COVA1-18 has a strong antiviral activity in three preclinical models and could be a valuable candidate for further clinical evaluation.
Assuntos
Anticorpos Monoclonais/administração & dosagem , Anticorpos Neutralizantes/administração & dosagem , Antivirais/administração & dosagem , Tratamento Farmacológico da COVID-19 , SARS-CoV-2/imunologia , Enzima de Conversão de Angiotensina 2/genética , Animais , Anticorpos Monoclonais/farmacocinética , Antivirais/farmacocinética , COVID-19/sangue , COVID-19/imunologia , COVID-19/virologia , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Feminino , Humanos , Pulmão/metabolismo , Pulmão/virologia , Macaca fascicularis , Masculino , Mesocricetus , Camundongos , Camundongos Transgênicos , SARS-CoV-2/isolamento & purificação , Distribuição Tecidual , Carga ViralRESUMO
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic is continuing to disrupt personal lives, global healthcare systems, and economies. Hence, there is an urgent need for a vaccine that prevents viral infection, transmission, and disease. Here, we present a two-component protein-based nanoparticle vaccine that displays multiple copies of the SARS-CoV-2 spike protein. Immunization studies show that this vaccine induces potent neutralizing antibody responses in mice, rabbits, and cynomolgus macaques. The vaccine-induced immunity protects macaques against a high-dose challenge, resulting in strongly reduced viral infection and replication in the upper and lower airways. These nanoparticles are a promising vaccine candidate to curtail the SARS-CoV-2 pandemic.
Assuntos
Vacinas contra COVID-19/administração & dosagem , Vacinas contra COVID-19/imunologia , Macaca fascicularis , Glicoproteína da Espícula de Coronavírus/química , Animais , Anticorpos Neutralizantes , Linfócitos B/imunologia , COVID-19/imunologia , COVID-19/prevenção & controle , Camundongos , Camundongos Endogâmicos BALB C , Modelos Animais , Nanopartículas/administração & dosagem , Coelhos , SARS-CoV-2/fisiologia , Glicoproteína da Espícula de Coronavírus/sangue , Linfócitos T/imunologia , Carga ViralRESUMO
The rapid spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has had a large impact on global health, travel, and economy. Therefore, preventative and therapeutic measures are urgently needed. Here, we isolated monoclonal antibodies from three convalescent coronavirus disease 2019 (COVID-19) patients using a SARS-CoV-2 stabilized prefusion spike protein. These antibodies had low levels of somatic hypermutation and showed a strong enrichment in VH1-69, VH3-30-3, and VH1-24 gene usage. A subset of the antibodies was able to potently inhibit authentic SARS-CoV-2 infection at a concentration as low as 0.007 micrograms per milliliter. Competition and electron microscopy studies illustrate that the SARS-CoV-2 spike protein contains multiple distinct antigenic sites, including several receptor-binding domain (RBD) epitopes as well as non-RBD epitopes. In addition to providing guidance for vaccine design, the antibodies described here are promising candidates for COVID-19 treatment and prevention.