This is an open-label, dose-ranging phase 1 trial of the PIV5 virus-vectored SARS CoV-2 S glycoprotein vaccine (CVXGA1) in healthy adults (males and nonpregnant females) 18 to 55 years of age that have not had a prior COVID vaccination (Groups 1 and 2), and in healthy adults 18 to 55 years of age (Groups 3) and adolescents 12-17 years of age (Group 4) who have received at least two doses of mRNA-based COVID vaccines (Pfizer Comirnaty® or Moderna Spikevax™) with the last dose at least 5 months prior to planned receipt of CVXGA1 study vaccine. The trial is designed to assess the safety, reactogenicity, and immunogenicity of a single dose of intranasal CVXGA1. Two dose levels will be assessed, CVXGA1-low lose (LD) at 106 plaque-forming units (PFU) (Group 1) and CVXGA1-high dose (HD) at 107 PFU (Groups 2, 3 and 4).
This Phase 1 trial is an open-label trial to evaluate the safety, reactogenicity and immunogenicity of two dosages (10^6 PFU and 10^7 PFU) of intranasal CVXGA1 administered as a single dose in healthy adults age 18-55 years and in adolescents age 12-17.