AstraZeneca vaccine 70.4% effective at preventing Covid-19 (Ld)

New Delhi, Dec 9 : Results of an interim analysis of the Phase III programme conducted by Oxford University with AZD1222, peer-reviewed and published in The Lancet on Wednesday demonstrated that the vaccine is safe and effective at preventing symptomatic COVID-19 and that it protects against severe disease and hospitalisation.
The interim analysis for efficacy was based on 11,636 participants accruing 131 symptomatic infections from the Phase III UK and Brazil trials conducted by Oxford University.
As announced on November 23, the primary efficacy endpoint of the programme statistical plan, based on the pooling of two dosing regimens, showed that the vaccine is 70.4 per cent effective at preventing symptomatic COVID-19 occurring more than 14 days after receiving two doses of the vaccine. A secondary efficacy endpoint of prevention of severe disease demonstrated no cases of severe infections or hospitalisations in the vaccine group.
A further analysis of the efficacy regimens showed that when the vaccine was given as two full doses, vaccine efficacy was 62.1 per cent and 90.0 per cent in participants who received a half dose followed by a full dose.
Vaccine efficacy was also assessed on the secondary endpoint of early prevention of severe disease after the first dose. There were no hospitalisations or severe cases of COVID-19 more than 21 days after the first dose of the vaccine. Ten participants in the control group were hospitalised due to COVID-19, among whom two were assessed as severe, including one fatal case.
More data will continue to accumulate as part of the upcoming primary analysis and further follow-up, refining the efficacy reading and characterising vaccine efficacy over a longer period of time.