The Oxford/AstraZeneca vaccine is 79 per cent effective at preventing Covid-19 and offers 100 per cent protection against severe disease, new data from a US-led trial has shown.
The jab, which has been the subject of controversy in Europe over concerns about links to very rare blood clots, is also 100 per cent effective at keeping people out of hospital with severe illness.
Some 32,449 people across all age groups took part in the phase three trial in the US, Chile and Peru, with a total of 141 cases of symptomatic Covid-19 reported.
The results showed that among people aged 65 and over, there was 80 per cent protection against developing Covid-19.
The degree of effectiveness for the jab was even higher than observed in the Oxford-led clinical trials.
Thrombotic events
An independent data safety monitoring board (DSMB) also identified no safety concerns related to the vaccine.
It conducted a specific review of thrombotic events, as well as cerebral venous sinus thrombosis (CVST) – the specific type of brain blood clot that has been troubling Europe.
The DSMB found no increased risk of thrombosis among the 21,583 participants receiving at least one dose of the vaccine. The specific search for CVST found no cases in this trial.
Andrew Pollard, professor of paediatric infection and immunity, and lead investigator of the Oxford University trial of the vaccine, said: “These results are great news as they show the remarkable efficacy of the vaccine in a new population and are consistent with the results from Oxford-led trials.
“We can expect strong impact against Covid-19 across all ages and for people of all different backgrounds from widespread us of the vaccine.”
We hope this will lead to even more widespread use of the vaccine
Sarah Gilbert, professor of vaccinology, and co-designer of the vaccine, said the new findings “provide further confirmation of the safety and effectiveness” of the jab.
She added: “In many different countries and across age groups, the vaccine is providing a high level of protection against Covid-19 and we hope this will lead to even more widespread use of the vaccine in the global attempts to bring the pandemic to an end.”
AstraZeneca will now submit data to the US Food and Drug Administration (FDA) and seek emergency approval for use.
As part of an agreement with Oxford, AstraZeneca is supplying the vaccine on a not-for-profit basis for the duration of the pandemic and in perpetuity for low and middle-income countries.
