ABSTRACT
This study evaluates safety of FINLAY-FR-02, a vaccine candidate against SARS-CoV-2 based on the recombinant receptor binding domain conjugated to tetanus toxoid, in a preclinical, repeat-dose toxicity and local tolerance study. Sprague Dawley rats were randomly allocated to three experimental groups: control (receiving physiological saline solution); placebo (receiving all vaccine components except antigens) and vaccine group (receiving three doses of the vaccine candidate, 37.5 µg of RBD) administered intramuscularly in hind limbs at 24 h intervals during three days. We evaluated physiological condition, pain, food and water consumption, body temperature, dermal irritability, injection site temperature and inï¬ammation, immunological response, blood chemistry, relative organ weight, histopathology and immunotoxicology. The product was well tolerated; no clinically relevant changes, pain, local effects or adverse systemic toxicological changes or deaths were observed. These preliminary results permitted the Cuban regulatory authorities to authorize clinical trials in humans.