BioNTech says it could produce and ship an updated version of its vaccine within 100 days if the new Covid variant detected in southern Africa is found to evade existing immunity.
The biotechnology company is already investigating whether the vaccine it developed with 辉瑞 works well against the variant, named Omicron, which has caused concern due to its high number of mutations and initial suggestions that it could be transmitting more quickly.
The company says it will know in two weeks whether its current vaccine is likely to be sufficiently effective against the B.1.1.529 variant, based on lab-based experiments.
If required, BioNTech said it is poised to tweak its vaccine to match it more closely to the new variant.
“Pfizer and BioNTech have taken actions months ago to be able to adapt the mRNA vaccine within six weeks and ship initial batches within 100 days in the event of an escape variant,”该公司在一份声明中说.
Other vaccine teams, including Johnson & 约翰逊, also confirmed on Friday that they were testing the effectiveness of their vaccines against the new variant to assess whether updates were likely to be required. AstraZeneca said it is already conducting research in Botswana and Eswatini, where the variant has been identified, to collect real-world data on how the Oxford/AstraZeneca vaccine performs against the new variant.
At the moment, concerns about a decline in protection are theoretical based on the very high number of mutations – double that seen in Delta – on the spike protein that the vaccine targets.
Human immune systems make a variety of antibodies that target several different places on the spike, so even if one bit of the spike changes, a vaccine will still typically work well.
然而, in B.1.1.529, nearly all the sites that antibodies target are different, and so scientists are particularly concerned this version could turn out to be an “escape variant”.
Prof Wendy Barclay, a virologist at Imperial College London, said the emergence of the variant made it even more crucial for people to access existing vaccines and have second and third doses. “Sometimes quantity [of antibodies] can compensate for the lack of match,“ 她说. “That is the only vaccine that’s available to us at the moment. We need to make that work as best as we can.”
Vaccines based on mRNA, such as the BioNTech/Pfizer and Moderna vaccines, are thought to be the easiest to alter. But most companies have been preparing for the eventuality of a so-called escape variant and have ambitious timeframes for distributing an updated vaccine, if deemed medically necessary and commercially feasible.
迄今为止, vaccines have held up well against new variants, such as Beta and Delta, but the emergence of these variants served as practice runs.
BioNTech/Pfizer and AstraZeneca are already running clinical trials on tweaked vaccines and discussing with regulators what new evidence would be needed to support their approval.
“Pfizer and BioNTech … have begun clinical trials with variant-specific vaccines (Alpha and Delta) to collect safety and tolerability data that can be provided to regulators as part of the blueprint studies in the event of an needed variant-specific vaccine,” the companies said in a statement.
约翰逊 & 约翰逊, which has developed a single-shot Covid vaccine and is selling it on a not-for-profit basis, like AstraZeneca, 说: “We are closely monitoring newly emerging Covid-19 virus strains with variations in the Sars-CoV-2 spike protein and are already testing the effectiveness of our vaccine against the new and rapidly spreading variant first detected in southern Africa.
“We remain steadfast in the benefit the Johnson & Johnson Covid-19 vaccine will provide to millions around the world.”