Participants will be enrolled into 2 ascending dose (RH109 low-dose 25 μg, high-dose 50 μg) cohorts randomly. Approximately 24 eligible participants, 12 for each cohort, will be randomized with a 3:1 ratio (RH109 : Placebo). The study will progress in a sequential manner, with the low-dose cohort being enrolled and dosed first. Dose escalation from low-dose to high-dose cohort is contingent on a review of safety data of the low-dose cohort through to 7 days following the vaccination by a Safety Monitoring Committee (SMC)
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the pathogen that causes a coronavirus-associated acute respiratory disease called coronavirus disease 19 (COVID-19), which is spreading all over the world. This virus can cause acute respiratory distress syndrome (ARDS) with a high fatality rate. In this phase I first-in-human clinical trial, healthy volunteers in two dose cohorts will be vaccinated Lyophilized COVID-19 mRNA Vaccine (RH109) The aim of the study is to assess the safety, reactogenicity and Immunogenicity of the candidate vaccine and to characterize its immunogenicity.