Covaxin efficacy 81%: Biotech

Ph 3 study involved 25,800; it can neutralise UK variant strains

Hyderabad-based 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. “Analysis from the National Institute of Virology also indicates that vaccine-induced antibodies can neutralise the UK variant strains and other heterologous strains,” Bharat Biotech said in a statement.

The trial process involved 25,800 subjects, the largest ever conducted in India, in partnership with the Indian Council of Medical Research (ICMR), the pharma firm said adding that 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.

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 explained.

“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 and 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.

In January, drug regulator DCGI 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 regimen 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.

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.

Covaxin and Covishield, both vaccines were cleared by the DCGI in early January, at a time when late-stage trial data for Covaxin was not available; it was cleared on the basis of Phase 1 and 2 data that confirmed its “safety and immunogenicity”.

Covaxin was given “restricted use in emergency situation in public interest”, meaning all those who were administered the drug as part of the vaccination drive were enrolled as part of the study.

Covaxin has been developed in collaboration with the ICMR on the WHO prequalified vero cell platform which is globally recognised with a well-established track record of safety.

“The development and deployment of Covaxin ensures that India has a powerful weapon in its arsenal in a continually evolving pandemic situation and will go a long way in helping us win the war against Covid-19.

“The need of the hour is to ensure that people in India continue to receive the vaccine and break the chain of virus transmission,” said Dr Samiran Panda, Head, Epidemiology and Communicable Disease, ICMR and Director, National AIDS Research Institute.

Thursday, 04 March 2021 | PNS | New Delhi