Search Results (2)

The research conducted in this preclinical study assesses QazCovid-live, a live attenuated COVID-19 vaccine created in Kazakhstan, by conducting preclinical evaluations of safety, immunogenicity, and allergenicity in various animal models, including mice, rats, hamsters, and guinea pigs. The vaccine, developed by attenuating SARS-CoV-2 via numerous Vero cell passages, had no significant adverse effects in acute and subacute toxicity assessments, even at elevated dosages. Allergenicity testing indicated the absence of both immediate and delayed hypersensitivity reactions. Immunogenicity evaluations revealed strong virus-neutralizing antibody responses, especially following intranasal and intratracheal delivery. Studies on reversibility and transmission further validated the vaccine’s stability and non-pathogenicity. The data indicate that QazCovid-live is safe, immunogenic, and prepared for clinical trials, presenting a potential strategy for COVID-19 prevention. Full article

Creating an effective and safe vaccine is critical to fighting the coronavirus infection successfully. Several types of COVID-19 vaccines exist, including inactivated, live attenuated, recombinant, synthetic peptide, virus-like particle-based, DNA and mRNA-based, and sub-unit vaccines containing purified immunogenic viral proteins. However, the scale and speed at which COVID-19 is spreading demonstrate a global public demand for an effective prophylaxis that must be supplied more. The developed products promise a bright future for SARS-CoV-2 prevention; however, evidence of safety and immunogenicity is mandatory before any vaccine can be produced. In this paper, we report on the results of our work examining the safety, toxicity, immunizing dose choice, and immunogenicity of QazCoVac-P, a Kazakhstan-made sub-unit vaccine for COVID-19. First, we looked into the product’s safety profile by assessing its pyrogenicity in vaccinated rabbit models and using the LAL (limulus amebocyte lysate) test. We examined the vaccine’s acute and sub-chronic toxicity on BALB/c mice and rats. The vaccine did not cause clinically significant toxicity-related changes or symptoms in our toxicity experiments. Finally, we performed a double immunization of mice, ferrets, Syrian hamsters, and rhesus macaques (Macaca mulatta). We used ELISA to measure antibody titers with the maximum mean geometric titer of antibodies in the animals’ blood sera totaling approximately 8 log2. The results of this and other studies warrant recommending the QazCoVac-P vaccine for clinical trials. Full article