Bharat Biotech on Saturday said the Covaxin booster trial has demonstrated “long-term safety with no serious adverse events." The vaccine maker said 90 per cent of recipients had a detectable neutralising antibody response against the wild-type strain, six months after the second dose.
Announcing the clinical trial results on safety and immunogenicity, the Hyderabad-based company said, “six months after a two-dose BBV152 vaccination series cell-mediated immunity and neutralising antibodies to both homologous (D614G) and heterologous strains (Alpha, Beta, Delta, and Delta plus) persisted above baseline, although the magnitude of the responses had declined.
Furthermore, Neutralising antibodies against homologous and heterologous SARS-CoV-2 variants increased 19- to 265- fold after a third vaccination. Booster BBV152 vaccination is safe and may be necessary to ensure persistent immunity to prevent breakthrough infections."
Chairman and Managing Director of Bharat Biotech, Dr Krishna Ella said, “These trial results provide a strong foundation towards our goal to provide Covaxin as a booster dose. Our goals of developing global vaccine against COVID-19 have been achieved with Covaxin indicated for adults, children, 2 dose primary and booster doses. This enables the use of Covaxin as a universal vaccine.”
While protection against the severe disease remains high across the full six months, a decline in efficacy against symptomatic disease over time and the continued emergence of variants are expected, it said. “Based on emerging data, Bharat Biotech believes that a third dose may be beneficial to maintain the highest levels of protection."