Covaxin Booster Dose To Ensure Long-Term Protection Against COVID: Bharat Biotech Study

New Delhi: Bharat Biotech, the manufacturer of Covaxin, has claimed that a third booster dose of the COVID vaccine may lead to maintain highest level of protection against the virus.

The pharma company in the country made the claim on the basis of a phase 2 randomised, double blind study conducted by it. Eleven institutions including ICMR, AIIMS, New Delhi and international collaborators participated in the study.

The study revealed that neutralisation titers against wild-type and Delta variants were 5 times higher in the people who took the third dose compared to those who have availed two-dose schedule.

While protection against COVID remains high for six months after two doses of Covaxin, a decline in efficacy and emergence of variants are expected over time, the findings of the study mentioned. “Based on emerging data, Bharat Biotech believes that a third dose may be beneficial to maintain the highest levels of protection,” TNIE quoted the company sources as saying.

The study results come at a time when the government is about to allow the most vulnerable population groups to avail a third Covid jab but with a caveat of having completed nine months since the administration of their second doses.

The research said a rise in immune capacity to neutralise the antibodies against Alpha, Beta, Delta plus was observed after analysing comparison between 184 previously vaccinated individuals who either received a third dose of Covaxin or placebo. The findings have been released on the preprint repository of medical science  MedRXiv.

The study also stated that the booster dose led to a marked rise in CD4+ T- and CD8+ Tcell response (types of T cells, an important arm of immunity) which may allow Covaxin to ensure long-term protective efficacy against severe SARS-CoV-2. Besides, 90% of recipients had a detectable neutralizing antibody response against the wild-type strain six months after the second dose.

“These trial results provide a strong foundation towards our goal to provide Covaxin as a booster dose,” TNIE quoted Krishna Ella, Chairman and Managing Director of Bharat Biotech as saying.