Messenger RNA (mRNA) vaccine technology has shown its power in preventing the ongoing COVID-19 pandemic. Two mRNA vaccines targeting the full-length S protein of SARS-CoV-2 have been authorized for emergency use. Recently, we have developed a lipid nanoparticle-encapsulated mRNA (mRNA-LNP) encoding the receptor-binding domain (RBD) of SARS-CoV-2 (termed ARCoV), which confers complete protection in mouse model. Herein, we further characterized the protection efficacy of ARCoV in nonhuman primates and the long-term stability under normal refrigerator temperature. Intramuscular immunization of two doses of ARCoV elicited robust neutralizing antibodies as well as cellular response against SARS-CoV-2 in cynomolgus macaques. More importantly, ARCoV vaccination in macaques significantly protected animals from acute lung lesions caused by SARS-CoV-2, and viral replication in lungs and secretion in nasal swabs were completely cleared in all animals immunized with low or high doses of ARCoV. No evidence of antibody-dependent enhancement of infection was observed throughout the study. Finally, extensive stability assays showed that ARCoV can be stored at 2–8 °C for at least 6 months without decrease of immunogenicity. All these promising results strongly support the ongoing clinical trial.
【저자키워드】 Vaccines, breath, 【초록키워드】 neutralizing antibody, SARS-CoV-2, Efficacy, Vaccine, High dose, vaccination, immunogenicity, clinical trial, Neutralizing antibodies, Antibody-dependent enhancement, mRNA vaccine, COVID-19 pandemic, Infection, lung, immunization, RNA, stability, Viral, Receptor-binding domain, animals, RBD, viral replication, mRNA, Lungs, temperature, macaque, nasal swab, mouse model, cynomolgus macaques, Emergency use, macaques, cellular response, dose, evidence of, no evidence of, lung lesion, lung lesions, Support, Messenger RNA, secretion, nasal swabs, messenger, full-length S protein, Complete, decrease, immunized, robust, shown, caused, significantly, characterized, the receptor-binding domain, elicited, 【제목키워드】 COVID-19, Efficacy, mRNA vaccine, stability,