Vaccination drive in Kalupur, Ahmedabad. (Express photo by Nirmal Harindran)
Bharat Biotech’s Covaxin vaccine has shown the ability to bring down symptomatic Covid-19 cases by 77.80 per cent, according to data from its much awaited phase 3 trials.
The results of the phase 3 trials come a day before the Hyderabad company’s scheduled meeting with the World Health Organization (WHO), where it is expected to submit its proposal for an Emergency Use Listing of the vaccine.
The EUL would make it easier for Covaxin — developed by Bharat Biotech in collaboration with the Indian Council of Medical Research (ICMR) — to receive recognition in other countries where it has not received regulatory approvals.
On Tuesday, a Subject Expert Committee (SEC) of the Central Drugs Standard Control Organization (CDSCO), the country’s apex drug regulatory body, reviewed and accepted data from late-stage clinical trials of Covaxin, said sources.
The data, collected from 25,800 participants, also included information related to the vaccine’s efficacy “for all forms of the disease”. This translates to the vaccine’s ability to reduce symptomatic Covid-19 cases compared with those who have not been vaccinated. “Everything was looked at — the efficacy, safety, lot-to-lot comparisons, etc,” said one of the sources on condition of anonymity.
SEC’s review and acceptance of this data is expected to offer more credence to Covaxin’s efficacy, which had become the subject matter of controversy starting with when it was granted restricted-use permission without this information in January.
“This is the final data on efficacy…it is effective, there is no doubt about it,” a source said.
However, SEC’s approval of this data does not mean that Covaxin will now be off restricted-use permission. “Although the company did want a complete authorisation… it was not agreed to,” said the source.
The company is expected to submit follow-up data on aspects like the safety of the vaccine for at least a year’s time before it is considered for such a status, the source added. “No Covid vaccine in the world has (full) authorisation for market use.”
Queries to Bharat Biotech on Tuesday night, about whether it sought full authorisation, remained unanswered until press time.
On March 3, Bharat Biotech and ICMR had announced that interim results from phase 3 trials of Covaxin showed that the vaccine has an efficacy of 80.60 per cent. On April 21, this figure was revised downward to 78 per cent against mild, moderate and severe Covid-19 disease. The lack of transparency over the fine print related to the vaccine’s efficacy had been red flagged by health experts.
According to senior officials of Bharat Biotech, the results from the phase 3 trial of the vaccine will be made available in an international scientific journal “very soon”.
On June 9, Bharat Biotech’s Covid Vaccines Project Lead Dr Raches Ella tweeted that the last volunteer in the phase 3 trial was vaccinated in mid-March. Data collected from all participants had to undergo a mandatory safety follow-up over two months. By mid-May, the company had “sufficient data for quality checks and analysis,” tweeted Ella.
According to another senior Bharat Biotech official, for its “pre-submission” meeting with the WHO planned for June 23, the Hyderabad vaccine maker will submit data from phase 2 and 3 trials on Covaxin. It will also give WHO a “very detailed” presentation on its submission for EUL.
Earlier this month, the US FDA had recommended that Covaxin makers apply for full authorisation instead of seeking Emergency Use Authorisation (EUA), thereby delaying a rollout of the vaccine in that country.