Safety, Reactogenicity, and Immunogenicity Trial of STX-S SARS-CoV-2 Vaccine in Adults

This phase 1 clinical trial will evaluate the safety, reactogenicity, and immunogenicity of STX-S in adults who have previously received a primary series and at least one booster with an authorized or licensed SARS-CoV-2 parenteral vaccine. The study is designed as a non-randomized, open-label, dose-escalation clinical trial evaluating three dose levels of STX-S. A sample size of 60 participants (20 participants per dose cohort) is anticipated. The primary objective is to evaluate the safety and reactogenicity of a single intramuscular injection of three different dose levels (25 ng, 50 ng, and 125 ng) of STX-S in previously vaccinated healthy adults. The secondary objectives are to evaluate the systemic anti-Spike humoral immune responses of a single Intramuscular (IM) injection of STX-S and to evaluate nasal mucosal Immunoglobulin A (IgA) and Immunoglobulin G (IgG) responses after study product administration.