Early data suggest two doses of the Oxford/AstraZeneca Covid-19 vaccine provide “minimal protection” against mild and moderate infection from the variant first identified in South Africa, the University of Oxford said Sunday.
Viral neutralization against the B.1.351 variant was “substantially reduced” when compared to the earlier coronavirus strain, according to a news release Sunday from the University of Oxford. The study, which has not been released, included about 2,000 volunteers who were an average of 31 years old; about half received the vaccine and half received a placebo, which does nothing. The vaccine’s efficacy against severe Covid-19, hospitalization and death were not assessed.
Details of the study by researchers from South Africa’s University of Witwatersrand and others and the University of Oxford were shared in a press release. The results have been submitted for peer-review and a preprint will be released soon, Oxford said.
After the study was reported Saturday by the Financial Times, AstraZeneca said in a statement it believes the vaccine could provide protection against severe disease, and said it has started to adapt the vaccine against the variant “so that it is ready for Autumn delivery should it be needed.”
“Efforts are underway to develop a new generation of vaccines that will allow protection to be redirected to emerging variants as booster jabs, if it turns out that it is necessary to do so,” Sarah Gilbert, a professor of vaccinology at the University of Oxford, said in Sunday’s statement, noting that this issue faces all vaccine developers. “We are working with AstraZeneca to optimise the pipeline required for a strain change should one become necessary.”
In the Oxford statement, Shabir Madhi, a professor of vaccinology at University of Witwatersrand who led the study, noted recent data in South Africa from Janssen, Johnson & Johnson’s vaccine arm, found some protection against moderate and severe Covid-19 disease with a similar vaccine.
“These findings recalibrate thinking about how to approach the pandemic virus and shift the focus from the goal of herd immunity against transmission to the protection of all at risk individuals in population against severe disease,” Madhi said.