The dose of COVID-19 vaccine from Oxford University / AstraZeneca is shown in its box at Princess Royal Hospital in Haywards Heath, West Sussex, UK, on 2 January 2021.
Gareth Fuller | Reuters
Drug maker AstraZeneca is rushing to adapt its Covid-19 vaccine to new variants of the virus, and the process becomes more urgent after a small-scale study found it was less effective in protecting against the most virulent strain discovered in the South. -Africa. .
The country said it would suspend the use of the shot in its vaccination program after a study, published Sunday and not yet peer-reviewed, found that the vaccine offered “minimal protection” against disease. mild to moderate caused by the South African variant.
Researchers from the University of the Witwatersrand and others in South Africa, and the University of Oxford, noted that the study was small, with only 2,000 volunteers with a mean age of 31 years. Oxford University said that “protection against moderate-to-severe illness, hospitalization or death could not be assessed in this study because the target population had such a low risk.”
Vaccine manufacturers had already begun developing second-generation Covid vaccines aimed at targeting new variants of the virus, and experts say it should not be too complicated to modify existing vaccines to cover mutations and that it could be adapted to a matter of six weeks.
Sarah Gilbert, a professor of vaccinology at Oxford University who developed the vaccine with AstraZeneca, said on Sunday that “work is underway to develop a new generation of vaccines that will redirect protection to emerging variants as vaccines. reinforcement, if it is necessary to do so “.
“We are working with AstraZeneca to optimize the pipe needed for a strain change if necessary. This is the same problem that all vaccine developers have and we will continue to monitor the emergence of new variants that appear in preparation for a future change of strain “.
The variant, formally known as the B.1.351 mutation, was first detected in South Africa in October 2020 and has since become dominant in the country.
Several cases have also been found elsewhere, which have sent health authorities to slow down to stop the spread of the mutation which has been shown to be more infectious. There was already concern that this variant might be more resistant to coronavirus vaccines developed over the past year.
Since it suspended the use of the AstraZeneca-Oxford University jab, the South African government will offer vaccines produced by Johnson & Johnson and Pfizer.
In late January, Johnson & Johnson reported that its single dose was 57% effective in one of its clinical trials in South Africa, where almost all cases of Covid-19 (95%) were due to an infection with the variant of B. 1,351 lineage. By way of comparison, the vaccine was found to be 72% effective in the American trial group.
Pfizer-BioNTech and Moderna have reported early indications that their vaccines offer protection against new known variants of the virus, those found in South Africa and the United Kingdom.
On Friday, Oxford University released details of a separate study showing that its vaccine was effective against a variant of the virus that was discovered in the south-east of England and has now become the strain. dominant in the United Kingdom.
Andrew Pollard, professor of pediatric infection and immunity, and chief researcher of the Oxford vaccine trial, said data from trials of his vaccine in the UK “indicate that the vaccine not only protects against virus of the original pandemic, but also protects against the variant novel, B.1.1.7, which caused the disease to rise since the end of 2020 across the UK ”.