Bharat Biotech's Covaxin is 77.8 per cent effective in protecting against COVID-19, according to data from Phase III trials conducted on 25,800 participants across India.
Sources said trial data and results were studied and recommended for approval by the DCGI's Subject Expert Committee on Tuesday. The data was submitted to the DCGI over the weekend.
The data has not yet been published in an internationally recognised, peer-reviewed journal; earlier this month Bharat Biotech said publication would only happen after submission to the regulator.
"First interim analysis" of Phase III results, presented in March, indicated Covaxin was 81 per cent effective in preventing COVID-19 in those without prior infection after the second dose.
Data available and analysed at that stage also showed a 100 per cent reduction in chances of hospitalisation in case of infection.
Phase III data approval will likely also help Bharat Biotech secure an EUL (emergency use listing) from the World Health Organization.
The company is expected to hold a 'pre-submission' meeting with WHO authorities on Wednesday, to discuss guidelines for final submission of required data and documents. According to news agency PTI, Bharat Biotech had already submitted 90 per cent of the required paperwork.
Last month Bharat Biotech said it expected to get WHO approval for Covaxin by September.
An EUL from WHO will allow the company to export Covaxin and enable easier international travel for Indians vaccinated with the drug, which is not yet recognised by some foreign governments.
Covaxin was cleared for emergency use last year while still in clinical trials; it was given "restricted use in emergency situation in public interest", which raised questions and was also seen as contributing to vaccine hesitancy that marked the early stages of India's vaccination drive.
Approved Phase III data will go help resolve doubts as the government looks to increase pace of vaccination to prep for a likely third wave and protect against mutated versions of the virus.
On Monday - the first day of the government's renewed vaccination push - a record number of doses - 88.09 lakh - were administered. Around 3.2 crore of those were Covaxin doses.
The challenge, now, is in maintaining those numbers over the next few months, with particular obstacles being supply of doses and delivering them to less accessible parts of the country.
Apart from Covaxin, the AstraZeneca-Oxford University vaccine (made and sold in India as Covishield) and Russia's Sputnik V are the only other shots available at this time. The government has said it is working with US pharma giants Pfizer and Moderna for use of their vaccines as well.
With input from PTI
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