HYDERABAD: The indigenously developed Covid-19 vaccine Covaxin protects people against the deadly Beta (B.1.351) and Delta (B.1.617.2) variants, more commonly referred to as the South African and Indian variants, a study has found.
The study, uploaded on bioRxiv, a site that carries preprints of research papers before they are peer-reviewed, was conducted by researchers from the NIV, ICMR and Bharat Biotech.
The research, conducted to evaluate the neutralisation potential of Covaxin, found a threefold and 2.7-fold reduction in neutralisation titers (concentration of neutralising antibodies) against the Beta and Delta variants.
Experts took sera of 17 people 28 days after they got both Covaxin jabs However, the researchers concluded that despite a reduction in neutralisation titer, the whole-virion inactivated vaccine demonstrated protective response against the two variants of concern.
“Our study demonstrated that despite a reduction in neutralisation titers with BBV152 vaccines sera against B.1.351 and B.1.617.2, its neutralisation potential is well established.
Lastly, the broad epitope coverage of an inactivated vaccine (BBV152) decreases the magnitude of reduced neutralisation against emerging variants,” the researchers said.
The study also found that the reduction in neutralising titers using sera of Covid-19 recovered cases was 3.3-fold and 4.6-fold against the Beta and Delta variants, respectively.
The study was conducted by collecting the sera of 20 people after 5-20 weeks of recovery from Covid-19.
This included 17 people who were infected with B.1 and three people infected with the B.1.617.1 lineage.
The researchers collected sera of 17 people who were vaccinated with Covaxin after 28 days of getting both shots.
The study looked at the neutralisation potential of the vaccine against the Beta and Delta variants as compared to the prototype B.1 (D614G).With the increasing threat of SARS-CoV-2 variants, it is imperative to assess the efficacy of currently available vaccines against these variants, the researchers said.