Covishield 90% effective if doses given 2-3 months apart: Poonawalla
The efficacy of the COVID-19 vaccine Covishield could increase to 90% if the two doses are given 2.5-3 months apart, Serum Institute of India CEO Adar Poonawalla said Monday. Covishield was developed by Oxford University and AstraZeneca and is being manufactured by SII. Earlier this year, a study said Covishield had an efficacy of 70% with a one-month gap between doses.
Efficacy increases for vaccines when dose-gap widened: Poonawalla
Speaking to India Today, Poonawalla said, "One arm of trials, in which doses were given one month apart, was 60-70% effective." "And there was another group of a 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%," he said, adding that other vaccines follow a similar trend.
Recently, Centre allowed increasing gap between doses to 8 weeks
Last month, the Centre had decided to increase the interval between the first and second doses of Covishield to up to eight weeks after the recommendation of the National Expert Group on Vaccine Administration. Global trials of the AstraZeneca vaccine found that the efficacy increased from 54.9% to 59.9% if the gap between two doses was raised from under six weeks to 6-8 weeks.
Vaccine offers protection after first dose: Poonawalla
Poonawalla also told the publication that the vaccine starts offering protection against the coronavirus after the first dose. "We found an excellent response below the age of 50 with one dose. We can say after a month, even with one dose, there is excellent protection, more than even what you find in a COVID-19 recovered patient," he said.
'Continue wearing masks, maintaining physical distancing after vaccination'
"About 70% of people are fully protected with one dose, but the second dose is necessary for long-term immunity protection," Poonawalla said. He also advised people to continue wearing face masks and maintaining physical distancing, even after receiving the second dose. Further, the SII CEO added that herd immunity may take up to a few years to come into effect.
SII developing another vaccine; trials underway
The SII is also working on the development of another vaccine, called Covovax, with the aim to launch it by September 2021. The vaccine is already undergoing trials in India. It is being jointly developed by the SII and US-based biotechnology company Novavax.
43 lakh vaccine doses administered over past day
Currently, India is using two vaccines in its nationwide vaccination drive: Covishield and Bharat Biotech's COVAXIN. As of Tuesday morning, 8,31,10,926 vaccine doses had been administered across India. The nationwide vaccination drive was launched on January 16, 2020. The Union Health Ministry's data showed on Tuesday that 43,00,966 doses were administered in the past 24 hours, the highest coverage in a single day.
