Bharat Biotech says Covaxin has 81 per cent clinical efficacy

Bengaluru: Bharat Biotech on Wednesday announced the first interim analysis of its BBV152 (COVAXIN). The whole virion inactivated COVID-19 vaccine candidate demonstrated an interim vaccine efficacy of 81% in its Phase 3 clinical trial. The trials involved 25,800 subjects, the largest ever conducted in India, in partnership with the Indian Council of Medical Research (ICMR).

"Today is an important milestone in vaccine discovery, for science and our fight against coronavirus. With today's results from our Phase 3 clinical trials, we have now reported data on our COVID-19 vaccine from Phase 1, 2, and 3 trials involving around 27,000 participants. COVAXIN demonstrates a high clinical efficacy trend against COVID-19 but also significant immunogenicity against the rapidly emerging variants," said Dr Krishna Ella, Chairman & Managing Director, Bharat Biotech.

BBV152 contains a whole virion inactivated SARS-CoV-2 vaccine, which is produced in Vero cells.

"I want to thank every one of the participants, who volunteered to participate in this vital clinical trial, our partners, principal investigators across 25 study sites, and our team at Bharat Biotech who dedicated their time to this vaccine discovery," said Suchitra Ella, Joint Managing Director, Bharat Biotech.

The Phase 3 study enrolled 25,800 participants between 18-98 years of age, including 2,433 over the age of 60 and 4,500 with comorbidities. The primary endpoint of Phase 3 clinical trial is based on the first occurrence of PCR-confirmed symptomatic (mild, moderate, or severe) COVID-19 with onset at least 14 days after the second study vaccination in serologically negative (to SARS-CoV-2) adult participants at baseline.

The first interim analysis is based on 43 cases, of which 36 cases of COVID-19 were observed in the placebo group versus 7 cases observed in the BBV152 (COVAXIN) group, resulting in a point estimate of vaccine efficacy of 80.6%.

The interim analysis included a preliminary review of the safety database, which showed that severe, serious, and medically attended adverse events occurred at low levels and were balanced between vaccine and placebo groups. Analysis from the National Institute of Virology indicates that vaccine-induced antibodies can neutralize the UK variant strains.