Safety and immunogenicity of SARS-CoV-2 recombinant  protein vaccine formulations in healthy adults :   interim  results of a randomised, placebo-controlled, phase 1–2,  dose-ranging study / 
Paul A Goepfert [and twenty two others] 
<br/><br/>Lancet Infect Dis . 2021 Apr 19; S1473-3099 (21) 00147-X. <br/>doi: 10.1016/S1473-3099(21)00147-X 
<br/><br/><label>Subjects--Topical Terms: </label><br/>COVID-19 Vaccines--immunology<br/>Placebo Effect