Covaxin is 81 per cent effective in preventing Covid and can work against the UK variant of the virus, Bharat Biotech said Wednesday as it revealed Phase III trial results for a vaccine that was cleared in January amid concerns over its safety and efficacy.
“… Covaxin demonstrated 81 per cent interim efficacy in preventing COVID-19 in those without prior infection after the second dose,” Bharat Biotech said in its statement.
The company said the “first interim analysis is based on 43 cases, of which 36 cases of COVID-19 were observed in the placebo group versus seven cases observed in the BBV152 (COVAXIN) group”.
The data has yet to be peer-reviewed.
Bharat Biotech said it expects to share further details as additional data becomes available.
“An additional interim analysis is planned for 87 cases, and the final analysis is planned for 130 cases. 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,” the company said.
The trial, which began in November last year, involved 25,800 participants – between 18 and 98 years old – across 25 sites, who were randomly divided into two groups.
The participants included 2,433 people over the age of 60 and 4,533 with co-morbidities.
One group was given the vaccine and the other got a placebo. 43 people (seven from the group that got the vaccine) were found to have coronavirus.
Interim analysis also showed that severe, serious, and medically attended adverse events occurred at low levels and were balanced between vaccine and placebo groups, Bharat Biotech said.
The company also said that “analysis from the National Institute of Virology indicates that vaccine-induced antibodies can neutralise the UK variant strains and other heterologous strains”.
Data from the third stage of trials – which measures the vaccine’s success in protecting against the coronavirus – has been widely anticipated amid concerns over Covaxin’s safety and efficacy, particularly as mutated, and more infectious, strains of the virus are circulating in the world.
Covaxin is one of two Covid vaccines to have been cleared for emergency use.
The other is Covishield, which was developed by AstraZeneca and Oxford University and is produced by Pune-based Serum Institute. Covishield has an efficacy rate of 70 per cent after the second dose.
Both vaccines were cleared by the Drug Controller General of India (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 I and II 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.
As the government launched the national vaccination drive on January 16, many expressed reservations about being given Covaxin, particularly since a choice of vaccines was not offered.
Doctors from Delhi and Karnataka were among those wrote to centre and state governments, asking to be given a choice in the vaccination process.
On Monday, as the second phase of the vaccination drive began, Prime Minister Narendra Modi rolled up his sleeve and got a shot of Covaxin at Delhi’s AIIMS to dispel any fears.
This morning the centre reported nearly 15,000 new Covid cases in the past 24 hours, with the active caseload increasing by around 1,700. As of March 1, of these the number of UK strain cases are 187.