Hyderabad: As India and the world grapple with the fear of another Covid surge triggered by BF.7 sub-variant of Omicron virus, work is underway to develop vaccines targeting the newer variants as existing vaccines are based on the Wuhan or original strain of SARS-CoV-2.
Hyderabad-based Bharat Biotech and other global companies, including Pfizer, Moderna are developing booster doses, which would be available only next year.
However, experts believe that in countries like India, where hybrid immunity (immunity obtained both by infection and vaccination) is common, new vaccines targeting Omicron sub-variants may have less impact.
“Around the world, companies are working on developing vaccines based on the new Omicron strain. But there may not be a significant difference in efficacy from the existing precautionary doses. Vaccines that can target all mutating variants are also being discussed,” said Rakesh Mishra, director of Tata Institute of Genetics and Society and former director of the Centre of Cellular Molecular Biology (CCMB), Hyderabad.
In June, US Food and Drug Administration (FDA) held a detailed discussion on the efficacy of the second booster dose. “Most experts agreed there was a need to include SARS-CoV2 Omicron component in Covid-19 vaccines used in the US,” said Dr Kiran Madala, a well-known researcher.
Sources said, with Bharat Biotech receiving the Omicron BF.7 strain for vaccine development as was told by the Centre in Parliament, the procedure may be in the pre-clinical stage and may take longer to develop than foreign vaccines.
Bharat Biotech uses the whole virus method rather than the mRNA method adopted by foreign firms that use only a portion of the virus to develop vaccines in a shorter time. The whole virus method of Bharat Biotech is exactly the opposite.
A few months ago, European Medicines Agency (EMA)’s human medicine committee strongly recommended that an adapted bivalent (two strains) vaccine targeting Omicron sub-variants BA.4 and BA.5 be approved.
It discussed Pfizer/new BioNtech’s booster vaccine based on Coronavirus Omicron variants.