Safety and Immune Response Study of Experimental and Authorized SARS-CoV-2 Booster Vaccines in Healthy Adults Aged 18 to 65 Previously Vaccinated with mRNA COVID-19 Vaccines

What this Trial Is About

Researchers are evaluating four different SARS-CoV-2 vaccines as booster shots in healthy adults aged 18 to 65 years who have previously received authorized mRNA COVID-19 vaccines. The trial compares two experimental vaccines, CD40.RBDv and CD40.Pan.CoV, both combined with the Hiltonol adjuvant, against two authorized vaccines, Comirnaty and Nuvaxovid. The study aims to assess the safety of the experimental vaccines and measure the immune response they trigger, including the durability of antibodies over time. Participants will receive a single vaccine injection at day 0, with the experimental vaccines given subcutaneously combined with Hiltonol, and the authorized vaccines administered intramuscularly. Alongside vaccination, participants will undergo two intradermal skin tests. The trial involves 10 hospital visits for medical examinations and collection of blood and saliva samples to monitor immune responses and safety over a period extending to 48 weeks. During the study, participants will keep a diary to record any symptoms or treatments they experience. Researchers will evaluate multiple safety outcomes, including adverse events shortly after vaccination and throughout the trial. Immunogenicity will be assessed by measuring neutralizing antibodies, T-cell responses, and other immune markers at various time points from day 0 through week 48. Participants commit to follow-up visits and testing according to the study schedule to support comprehensive monitoring of vaccine effects.

An Experimental Medicine Multicenter Trial to Evaluate the Safety and Immunogenicity of Experimental Versus Authorized SARS-CoV-2 Vaccine Candidates as a Booster Dose in Healthy Participants Previously Vaccinated With Authorized mRNA SARS-CoV-2 Vaccines.