AstraZeneca’s vaccine shows efficacy in preventing symptomatic Covid-19

AstraZeneca has reported that interim analysis from the Phase III programme of the Covid-19 vaccine, AZD1222, showed it is safe and effective at preventing symptomatic Covid-19.

Data published in The Lancet demonstrated that AZD1222 protects against severe disease and hospitalisation.

Co-invented by the University of Oxford and Vaccitech, AZD1222 uses a replication-deficient chimpanzee viral vector based on an adenovirus. It also has the genetic material of the SARS-CoV-2 virus spike protein.

A total of 11,636 subjects accruing 131 symptomatic infections in the Phase III UK and Brazil trials conducted by Oxford University formed the basis for the interim analysis.

As announced last month, the primary efficacy endpoint based on combining two dosing regimens showed that the vaccine was 70.4% effective at preventing symptomatic Covid-19 occurring more than 14 days after receiving two doses.

In addition, the interim analysis showed that AZD1222 was effective in preventing Covid-19 and no severe cases or hospitalisations were observed more than 21 days after the first injection.

When the vaccine was given as two full doses, the efficacy was 62.1% and 90% in subjects who received a half dose followed by a full dose.

The latest data also confirmed that the vaccine remained well-tolerated, with no serious safety events observed related to the vaccine.

So far, the safety data published has been obtained from over 20,000 participants enrolled across four clinical trials: COV001 and COV002 in the UK, COV003 in Brazil and COV005 in South Africa.

AstraZeneca CEO Pascal Soriot said: “The results show that the vaccine is effective against Covid-19, with in particular no severe infections and no hospitalisations in the vaccine group, as well as safe and well-tolerated.

“We have begun submitting data to regulatory authorities around the world for early approval and our global supply chains are up and running, ready to quickly begin delivering hundreds of millions of doses on a global scale at no profit.”