The goals of this clinical trial are: 1. Phase 2: to test a gamma adapted recombinant vaccine against SARS-CoV-2 in healthy adult volunteers, previously vaccinated against the SARS-CoV-2 virus. 2. Phase 3 (first volunteer enrollement on March 25, 2023): to test a recombinant vaccine against SARS-CoV-2 comparing three different versions (Gamma Variant RBD-based ARVAC-CG vaccine, Omicron Variant RBD-based ARVAC-CG vaccine, Bivariant Gamma/Omicron RBD-based ARVAC-CG vaccine), in adult volunteers previously vaccinated against the SARS-CoV-2 virus The main questions to be answered are: 1. Phase 2: 1. What si the immune response after one dose of vaccine? 2. What is the safety and tolerability profile of this vaccine? 2. Phase 3 : 1. What is the immune response triggered by each vaccine formulation against Wuhan, gamma, and omicron variants. 2. What is the safety and tolerability profile of this vaccine? In phase 2, participants will receive one dose of the study vaccine and one dose of placebo 28 days apart, in a cross-over design. In phase 3 (not yet recruitment), participants will be randomized to receive one of the three possible types of vaccines and all of them will receive one dose of the corresponding vaccine and 1 dose of placebo 28 days apart, in a cross over design.
Vaccine containing 50 µg of antigen + Alum. Schedule: One booster dose of vaccine Administration route: intramuscular (IM) injection
Vaccine containing 50 µg of antigen + Alum. Schedule: One booster dose of vaccine Administration route: intramuscular (IM) injection
Vaccine containing 25 µg of gamma antigen + 25 µg of omicron antigen + Alum Schedule: One booster dose of vaccine Administration route: intramuscular (IM) injection
Schedule: One dose of placebo in a crossover design Administration route: intramuscular (IM) injection
Buenos Aires, Buenos Aires F.D., Argentina
Buenos Aires, Buenos Aires F.D., Argentina
Argentina, C.a.b.a., Argentina
Córdoba, Córdoba Province, Argentina
Buenos Aires, Argentina
Buenos Aires, Argentina
Buenos Aires, Argentina
Buenos Aires, Argentina
Buenos Aires, Argentina
Ciudad de Buenos Aires, Argentina
Salta, Argentina