Development of a recombinant formulation as booster for different SARS-CoV-2 vaccine platforms.

KARINA PASQUEVICH; LORENA CORIA; JUAN MANUEL RODRIGUEZ; MONICA LOMBARDO; DIEGO ÁLVAREZ; CELESTE PUEBLAS CASTRO; ELIANA CASTRO; LAURA BRUNO; LUCAS SAPOSNIK; FEDERICO MONTES DE OCA; JULIO VEGA; JUAN FLÓ; JORGE CASSARÁ; JULIANA CASSATARO

Congreso; World Vaccine Congress 2022; 2022

Our group has been working on the development of adjuvants for vaccines against infectious diseases. When pandemic started, in May 2020 we focused on the development of a vaccine against SARS-CoV-2 that can be produced in Argentina, can be adapted for new emerging variants of concern (VOC) of the SARS-CoV-2 virus and that can be used as primary or booster vaccine.The project is currently being developed in Argentina by our group in the University of San Martin together with the Pablo Cassará Foundation and the Pablo Cassará S.R.L. Laboratory (100% Argentine shareholders). To date we have performed preclinical studies in different animal species to evaluate the toxicity and immunogenicity of the developed vaccine. The vaccine formulation elicited high levels of neutralizing antibodies of the virus and induced a specific T cell response in line with the current requirements for vaccines against COVID19. Vaccine-induced antibodies can neutralize different VOCs. In addition, in an animal model of severe disease, the vaccine induced protection against the experimental challenge with SARS-CoV-2. Preclinical toxicological studied of the prototype vaccine have been completed in December 2021 and in March 2022 we received the regulatory approval to start a phase 1 clinical trial in 80 vaccinated individuals. Preliminary results of this ongoing phase 1 study showed that the vaccine was safe and was able to boost the neutralizing antibody response against different VOCs including Ómicron irrespective of the primary vaccination platform of the study participants. We expect to conduct and complete phase 2/3 trial during 2022.