The head of Bharat Biotech expressed confidence at a press conference on Monday that Covaxin, the vaccine candidate developed by the company, will be effective on mutant strains of the novel coronavirus — a major reason why the candidate has been granted approval for restricted use.
The company will be able to establish the “hypothesis” of the candidate’s ability to protect against mutations in a week, chairman and managing director Dr Krishna Ella said.
“It’s only a hypothesis right now…but just give me one week’s time (and) I’ll give confirmatory data,” Dr Ella said. He was responding to a question on whether there were data to show Covaxin is effective against the mutant strain of the SARS-CoV-2 virus that was first detected in the United Kingdom and has since been found in more than 30 other countries.
Evidence from vaccines for other viruses like rabies support the hypothesis, Dr Ella said — because of the platform it uses, Covaxin would be highly effective against such mutations. The vaccine uses an inactivated platform – it was developed by using killed strains of the SARS-CoV-2 virus.
Bharat Biotech, which has sent around 5 million doses of its candidate for quality checks and clearances at the Central Drugs Laboratory in Kasauli, hopes to be able to roll out the vaccine for use among the public as soon as possible. It has stockpiled around 10 million doses, and will be ready with another 10 million by February, Dr Ella said. “We will be ready with 150 million doses by July-August,” he added.
Covaxin to protect against mutants, data in a week: Bharat Biotech
Extra shot in arsenal
The firm is also preparing a protocol to expand the testing of its vaccine to children aged 2-15 years, which will be submitted to an expert committee of the country’s drug regulatory body soon, he said.
However, no procurement deal has been finalised as yet. The company has not said what the cost for the two-dose vaccine may be.
“Right now, the government is talking to us,” Dr Ella said. “The cost is (based on) the size of the volume/scale. In the beginning, the cost may be a little higher in the vaccine field, but as the scale-up of production increases, when market competition builds up, the price is automatically controlled by the market,” he said.
“We are trying to understand a lot of things…just give us time; we’ll figure out all those things.”
Bharat Biotech has been criticised for seeking approval for Covaxin without providing data on the vaccine’s efficacy, that is, its ability to bring down the number of symptomatic Covid-19 cases.
While Drug Controller General of India (DCGI) Dr V G Somani on Sunday granted restricted use approval “in clinical trial mode” to Covaxin “in public interest”, the regulator did not clarify whether the approval had been granted on the basis of efficacy data. The firm has submitted pre-clinical testing data, and phase 1 and 2 safety and immunogenicity data.
Dr Ella said the approval means that the firm will no longer require to have a placebo group in its ongoing clinical trial, and will vaccinate people in an open-label format. “Their safety and efficacy, we’ll monitor them,” he said.
He added that the firm was still trying to figure out various modalities of vaccinations and the clinical trials for Covaxin following the approval, including whether a new clinical trial protocol would have to be submitted, and whether they would be responsible for serious adverse events that develop during this phase of vaccination.
AIIMS Director Dr Randeep Guleria, member of the national Covid-19 task force, had told The Indian Express on Sunday that the approval granted to Covaxin was “like a back-up”.
“If we find that cases don’t rise, then we stick to the SII (Serum Institute of India, which has manufactured the Indian variant of the Oxford-AstraZeneca vaccine) till the Bharat Biotech data comes early next month… They (the regulators) have given, I would say, a green signal to start stockpiling in case we need it,” Dr Guleria had said.
Responding to a question from The Indian Express at the virtual media briefing on Monday, Dr Ella said: “We have not submitted any interim efficacy data at all. What we have done is, we have produced (data on the) highest antibody response, long-term immunogenicity and how neutralisation protection is there.”
The efficacy from late-stage trials of Covaxin on nearly 26,000 participants will become clearer between March and October 2021, which is the efficacy readout timeline set for the vaccine as per the design of the trial.
The inactivated platform is “proven”, and the technology allows the vaccine to target various components of the virus, like the membrane glycoprotein and nucleoprotein, in addition to the spike protein, Dr Ella said.
“Many people are (targeting) the spike protein. If spike protein doesn’t work, what will happen…then the nucleocapsid (protein shell of the virus that encloses its genetic material) also can take over the responsibility of vaccine response. And that is why we are confident this (Covaxin) will also protect against any UK mutant strains….”
There is also a precedent for granting emergency approvals despite a lack of efficacy data, Dr Ella said. The vaccines approved in India and abroad against H1N1 in 2009 had not done efficacy trials, he said.