The administration of the third dose of Bharat Biotech’s COVID-19 vaccine Covaxin (BBV152) after six months of two-dose vaccination dramatically increased neutralising antibody responses against both homologous and heterologous strains (Alpha, Beta, Delta, Delta Plus, and Omicron) and showed increased memory B cell response in subjects in controlled clinical trials, the company announced on Wednesday.
According to the company, the findings are based on a comprehensive study that demonstrated multiple benefits of Covaxin, including long-term immune response, cell mediated immunity, booster dose safety, immunogenicity against spike protein, N protein, and neutralising antibody responses against alpha, beta, delta, delta plus, and omicron variants.
According to the study, Covaxin-induced strong T cell responses remained for six months following antibody decrease. These T cell responses in vaccinated people were tracked for up to 12 months, regardless of whether the third dosage was received. T cell responses, in turn, aid in the production of B cell memory responses in response to antigen re-exposure. As a result, Covaxin gives long-term immunity.
According to Bharat Biotech, immune responses decreased after six months but surged by 40 times in those who got a booster dosage. When tested against variations of concern, immune responses lasted up to 12 months.
The trial included 184 participants who were randomly assigned to either a booster dose of BBV152 or a placebo 6 months following the initial series of two doses.
According to the business, subjects were examined for safety, neutralising antibody responses against worry variants, binding antibodies against spike protein, RBD, N proteins, and memory T and B cell responses to indicate cell-mediated immunity.
Dr Krishna Ella, Chairman and Managing Director, Bharat Biotech, said, “Our team has now demonstrated that Covaxin is a multi-epitope vaccine with antibodies against spike, RBD and N proteins. Post booster dose, it has proven to neutralize antibody responses against variants of concern and long term protection through memory T and B cell responses. We have now achieved our goal of developing a safe and efficacious vaccine with long-term protection against a spectrum of variants.”
Covaxin, according to Bharat Biotech, is manufactured in such a way that the same dosage may be given to adults and children for both main and booster doses, making it a universal vaccine.
Bharat Biotech claims to have more than 50 million doses of Covaxin on hand, ready to be delivered as needed.