India’s subject expert committee (SEC) on Covid-19 vaccines has been mercurial in its approval processes.
On Feb. 24, India’s drug authority refused to authorise Sputnik V, the vaccine developed in Russia and under a bridging trial in the country, for emergency use. The government authority has asked Dr Reddy’s, the Indian pharmaceutical company facilitating the trials in the country, to supply data on immunogenicity, according to a source-based report in The Economic Times newspaper.
Safety and immunogenicity data are collected during the first two phases of human trials, and efficacy data are generated once phase 3 trials end. The vaccine committee bases its approval decisions based on the data available and its own assessment. And this is where the conundrum lies.
The SEC approved two Covid-19 vaccines for emergency use in the country on Jan. 3. These were India’s homegrown vaccine Covaxin, which is manufactured by Bharat Biotech, and Covishield, which is made from the Oxford-AstraZeneca master seed by Serum Institute of India (SII). American pharmaceutical company Pfizer had also applied for authorisation for its mRNA vaccine.
While there were several consultations and meetings with drug makers, where the SEC asked for additional data, the approvals were finally given based on modified standards. For instance, Covaxin was granted restricted approval in “clinical trial mode” without any efficacy data. The government later explained that “the immunogenicity data generated through phase two clinical trials serve as a surrogate for efficacy,” according to Balram Bhargava, chief of the Indian Council for Medical Research.
In the case of Covishield, the immunogenicity data was still being generated when the SEC granted its approval for the vaccine. It considered the promising trial data emerging from the UK and Brazil, studies of which were published in The Lancet journal.
By that yardstick, Sputnik V should have also received clearance, according to epidemiologists. Experts have questioned this move especially since some studies have demonstrated the vaccine’s efficacy to be over 90%, at par with protections offered by the Pfizer and Moderna vaccines.
Similarly, Pfizer chose to withdraw its application for emergency after the SEC asked for detailed data and studies. The government has indicated often that a local, bridging study will be required for any vaccine maker to be considered for approval in the country.
This will be a policy hurdle that Johnson & Johnson’s pharmaceutical company, Janssen, will also need to clear for its single-dose vaccine. Janssen has tied-up with India’s Biological E for producing 600 million doses of its Covid-19 vaccine. At the moment, Janssen has not applied for emergency approval in India.