AstraZeneca has confirmed that the vaccine developed by it offers limited protection against the South African variant of COVID-19.
The British–Swedish multinational pharmaceutical and biopharmaceutical company AstraZeneca has confirmed that the Coronavirus (COVID-19) vaccine developed by it in collaboration with University of Oxford, offers limited protection against the South African variant of COVID-19.
The variant discovered in South Africa is known as 501.V2. It is more infectious than the original virus and could be responsible for driving the country’s current resurgence of the disease. Researchers and officials report that the prevalence of the variant is higher among young people with no underlying health conditions and more frequently causes serious illness in such cases than other variants.
The 501Y.V2 variant, dominant in South Africa, has recently been discovered in countries all over the world, including the United States (U.S.) and United Kingdom (U.K.).
The study, led by South Africa’s University of the Witwatersrand and Oxford university saw more than 2,000 participants with a median age of 31. Half the group was given at least one dose of placebo, with the other half receiving at least one dose of vaccine. Though none of the patients in the study died or were hospitalised, the findings, which have not yet been peer reviewed, could complicate the race to roll out vaccines as new strains emerge.
Speaking on the occasion, the Director of the Vaccines & Infectious Diseases Analytics (VIDA) Research unit at the University of the Witwatersrand, and Chief Investigator on the trial in South Africa – Shabir Madhi said, “Recent data from a study in South Africa sponsored by Janssen which assessed moderate to severe disease, rather than mild disease, using a similar viral vector, indicated that protection against these important disease endpoints was preserved.”
He further added, “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.”
The lead researcher on the Oxford Vaccine Development Programme – Sarah Gilbert said, “What we’re seeing from other vaccine developers is that they have a reduction in efficacy against some of the variant viruses.”
She further said, “What that is looking like is that we may not be reducing the total number of cases. There’s still protection in that case against deaths, hospitalisations and severe disease.”
Any setback for the efficacy of the AstraZeneca vaccine would be particularly crucial for the developing world, as the partners are producing billions of doses on a non-profit basis during the pandemic.
The AstraZeneca said, “We do believe our vaccine could protect against severe disease, as neutralising antibody activity is equivalent to that of other Covid-19 vaccines that have demonstrated activity against more severe disease, particularly when the dosing interval is optimised to 8-12 weeks.”
Meanwhile, Oxford University declined to comment on the results of the study, saying only that it was working with partners across the globe, including in South Africa, to evaluate the effects of new variants on the first generation of its COVID-19 vaccine.
South Africa has taken 1 million doses of the AstraZeneca vaccine last week. The 2-dose regimen did not show protection against mild-moderate COVID-19.
Separately, both Johnson & Johnson and Novavax have said their vaccines were less effective against the strain in clinical trials conducted in South Africa. Moderna has said it will test a booster shot and a reformulated vaccine to target the South African variant, after studies showed its vaccine was significantly less effective. The Pfizer – BioNTech vaccine was also slightly less effective in a lab study using a pseudo virus with some mutations from the 501Y.V2 variant.
