NEW DELHI, Apr 6: After the central government extended the gap between the two doses of Corona vaccines to six to eight weeks, the manufacturer of the “Covishield” vaccine the Serum Institute of India (SII) has claimed an increased efficacy of the vaccine if the two jabs are separated by two and half to three months (10 to 12 weeks).
Adar Poonawalla, the chief executive officer of the Pune-based SII, the world’s biggest vaccine maker, said the efficacy of Covishield rises to as much as 90 per cent if the two shots are separated by about 2.5-3 months. Covishield is developed by the Oxford University in collaboration with pharma giant AstraZeneca. Adar Poonawalla’s Serum Institute of India is manufacturing the Indian version of the COVID-19 vaccine under license from AstraZeneca.
“One arm of trials, in which doses were given one month apart, was 60-70 per cent effective. And there was another group of few thousand patients where they gave a gap of 2-3 months between the two doses. That is where they found the efficacy to be 90 per cent,” Poonawalla said.
His comments came weeks after the Indian government increased the gap between the first and second doses of Covishield to up to eight weeks. This was recommended by the National Expert Group on Vaccine Administration after data from trials in other countries suggested that the efficacy of the vaccine increases when the second dose is given more than six weeks after the first.
Poonawalla also claimed that one dose of Covishield itself give significant protection from COVID-19 to people below 50. “About 70 per cent of people are fully protected with one dose, but the second dose is necessary for long-term immunity protection,” he said. He underlined that wearing of face mask and social distancing are important even after taking two doses of the Covid-19 vaccine.
(Manas Dasgupta)