Covaxin efficacy determined 14 days post second dose, says Bharat Biotech as Anil Vij tests positive
It also clarified that phase 3 involves double-blind clinical trial – neither the company nor the participants know who receives vaccines and who gets placebos.
Hyderabad-based pharmaceutical firm Bharat Biotech on Saturday clarified that the efficacy of its vaccine, Covaxin, can only be determined 14 days after a second dose, ANI reported. The company issued a statement immediately after Haryana Health Minister Anil Vij, who had received a trial dose on November 20, tested positive for the coronavirus.
Bharat Biotech said its clinical trials of the vaccine were based on a two-dose schedule, given 28 days apart.
“The vaccine efficacy will be determined 14 days post the second dose,” the statement said. “Covaxin has been designed to be efficacious when subjects receive both doses. The phase-3 trials are double-blinded and randomized, where 50% of subjects [participants in the trial] receive vaccine and 50% of subjects receive placebo.”
In a double-blind clinical trial, a gold standard for testing new medicines or vaccines, neither the company nor the participants know who receives vaccines and who gets placebos, which maybe a similar-looking injection having no medical effect. Only an independent review board has access to that information.
The Ministry of Health and Family Welfare also clarified that Vij only took the first dose of the Bharat Biotech’s indigenous vaccine, which is being developed in collaboration with the National Institute of Virology and the Indian Council of Medical Research.
“The antibodies against the infection build up in a human being only after a specific number of days pass after the second dose of the vaccine is taken,” the ministry said, according to PTI. “Since, this is a two-dose vaccine. The minister in question has taken only one dose of the vaccine.”
On November 16, Bharat Biotech had announced the beginning of the phase 3 clinical trials Covaxin in India, with 26,000 participants from across 22 sites in the country. The vaccine has so far been evaluated in 1,000 subjects in Phase I and Phase II clinical trials, the company added.
Vij, who is also Haryana Home Minister, was one of the participants in the phase three trial of Bharat Biotech’s Covaxin vaccine. The 67-year-old leader has been admitted to the Civil Hospital in Ambala.
