Betacoronavirus/drug effects, Pandemics/prevention & control, Coronavirus Infections/drug therapy, Pneumonia, Viral/drug therapy, Viral Vaccines/pharmacology, Governmental Research Institutes, Investigational New Drug Application/methods, Clinical Trial, Phase II, Brazilian Health Surveillance Agency, Healthy Volunteers, Health Personnel, Vaccine Potency, COVID-19, Plano São Paulo, Coronavac, Instituto Butantan, Sinovac Biotech