'Need more scientific data to clarify’: Centre on mixing of Covid-19 vaccines

A couple of studies have been initiated on the mixing of Covid-19 vaccines in Christian Medical College in Vellore, Tamil Nadu, said Renu Swarup, secretary of the Centre's department of biotechnology. However, she added that additional data is needed to get better clarity on the mixing of vaccines.

“DCGI has given permission to CMC Vellore to start a trial on the mixing of vaccines. A couple of such studies have been initiated. We need more scientific data to get more clarity,” she told news agency ANI.

Notably, the Drugs Controller General of India (DCGI) in August accepted a proposal by the CMC Vellore for conducting research to gauge the mixing of one dose each of Covaxin and Covishield. “Permission has been granted for research study at CMC Vellore,” Niti Aayog member, Dr VK Paul said at the time.

The study is being conducted with as many as 300 volunteers who are inoculated with a dose each of Covaxin and Covishield – the first two coronavirus vaccines to receive approval from the DCGI in India. It’s aimed at finding out if a person can be administered two different doses of Covid-19 vaccines to be fully vaccinated against the virus, instead of receiving two jabs of the same vaccine.

The nod from the DCGI in August came around the time the Indian Council of Medical Research (ICMR) revealed that mixing Covaxin and Covishield can potentially offer better results.

Also Read | Covishield, Covaxin mix can give better results, says ICMR

However, the catch is that the ICMR study was an evaluation of 18 people from Uttar Pradesh’s Siddharth Nagar, who were inoculated with two different coronavirus vaccines by mistake. These people had taken Covaxin as their second dose, only six weeks after being administered Covishield as their first. The ICMR study found that this combination actually stimulated better immune responses in their systems than twin jabs of the same Covid-19 vaccine typically do.

Also Read | Canada stands by decision to mix and match Covid-19 vaccines despite WHO warning

Several studies have been in favour of mixing coronavirus vaccines on a global platform as well. In June, a study led by Oxford University found that alternating doses of AstraZeneca and Pfizer-BioNTech Covid-19 vaccines generate robust immune responses against the infection.