New Delhi: Bharat Biotech on Wednesday said its COVID-19 vaccine Covaxin has demonstrated an interim vaccine efficacy of 81 per cent in Phase 3 clinical trials.
The process involved 25,800 subjects, the largest ever conducted in India, in partnership with the Indian Council of Medical Research, the Hyderabad-based firm said in a statement.
The Phase 3 study enrolled participants between 18-98 years of age, including 2,433 over the age of 60 and 4,500 with comorbidities, it added.
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 COVAXIN group, resulting in a point estimate of vaccine efficacy of 80.6 per cent, Bharat Biotech said.
“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,” Bharat Biotech Chairman & Managing Director Krishna Ella said.
Covaxin demonstrates a high clinical efficacy trend against COVID-19 but also significant immunogenicity against the rapidly emerging variants, he added.
On Monday, Prime Minister Narendra Modi was administered Covaxin on the very first day of expansion of the inoculation drive to cover people aged 60 and above and those between 45-59 having co-morbidities.
In January India’s drugs regulator had approved Oxford COVID-19 vaccine Covishield, manufactured by the Serum Institute, and indigenously developed Covaxin of Bharat Biotech for restricted emergency use in the country, paving the way for a massive inoculation drive.
Covishield had shown an efficacy rate of 70 per cent after two full doses. However, one of the regimens with a half dose and a full dose showed 90 per cent efficacy against the virus.
Bharat Biotech said the interim analysis of its vaccine 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, the company said.
The trial’s conduct and monitoring are as per good clinical practice guidelines and have been outsourced to IQVIA, it added.
“Analysis from the National Institute of Virology indicates that vaccine-induced antibodies can neutralize the UK variant strains and other heterologous strains,” Bharat Biotech said.
The company expects to share further details of the trial results as additional data becomes available, it noted.
Additional interim analysis is planned for 87 cases, and the final analysis is planned for 130 cases, the company said. All data from the second interim and final analyses will be shared via pre-publication servers as well as submitted to a peer-reviewed journal for publication, it added.
Bharat Biotech said more than 40 countries globally have expressed their interest in Covaxin.