While countries shut borders to travellers from southern Africa fearing the spread of a new strain of the virus that causes Covid-19, vaccine makers were racing to get their hands on it to test if their products will still work.
The World Health Organization formally raised the alarm on Thursday about the B.1.1.529 variant — now known as “Omicron” — which has a worrying array of mutations. But Moderna said its team had already been working “nonstop” on it for the past few days, while researchers at BioNTech are using a pseudovirus — engineered to look like the new strain — with the aim of discovering if their vaccines will be less effective against the strain within the next two weeks.
Johnson & Johnson said it was already testing its vaccine against the strain, while University of Oxford scientists are expecting a delivery of the virus imminently, according to a person familiar with the matter. AstraZeneca said it was already conducting research in Botswana and Eswatini, where the variant is present, to assess how its vaccine stood up to the new variant.
The vaccine makers are reliving a familiar rodeo. They ran the same lab tests as the Alpha, Beta and Delta strains emerged. They expected new variants and have been preparing by running clinical trials to test new versions. AstraZeneca is set to deliver results on its first modified vaccine, for the Beta variant, soon, and Pfizer and BioNTech are conducting trials of vaccines tweaked for the Alpha and Delta variants.
But this is the first time that a variant has displayed so many mutations in a key place: the “spike” protein that it uses to infect human cells. Francois Balloux, a professor at the UCL Genetics Institute, said these changes meant the neutralising antibodies that protected people who had been vaccinated or previously infected were less likely to recognise this variant.
Jo Walton, an analyst at Credit Suisse, said all the currently approved vaccines were focused on the spike protein, so they could all prove slightly less protective.
But mRNA vaccines should be easier to adapt because they simply deliver genetic codes in tiny bubbles of fat, then use the body as a factory to make the protein the immune system needs to recognise. These codes can be quickly swapped out and there is no need for the enormously time-consuming process of growing cells in tanks that is required for other types of vaccine.
“mRNA should be the easiest: you can get a new cassette and put it in and so if you need it, you should be able to produce a new vaccine,” said Walton.
Shares in mRNA vaccine makers jumped on Friday: Moderna rose 21 per cent, BioNTech gained 17 per cent and Pfizer was up 7 per cent. CureVac rose 12.5 per cent even though it is yet to have a vaccine approved. The German company said it could test its vaccine candidate with partner GSK within a couple of weeks.
BioNTech said it and Pfizer had taken action “months ago” to adapt the mRNA vaccine they developed together within six weeks and to ship initial batches within 100 days, in case there was an “escape variant”.
Pfizer recently said it had cut the time from the start of the process to putting vaccines into vials from 110 days to 31.
While adenovirus vector vaccines such as the Oxford/AstraZeneca and Johnson & Johnson jabs are also fairly easy to adapt, they are far trickier to scale up. Michael Leuchten, a UBS analyst, said this was shown in the struggles AstraZeneca had with production earlier this year.
“Adenovirus vectors do not like scaling up. They take personal offence to that,” he said.
One vaccine that could benefit is at present being reviewed by regulators. Valneva’s whole inactivated vaccine teaches the immune system how to recognise other key proteins as well as the spike. Shares in the French vaccine maker rose 8.5 per cent on Friday over hopes that it may be better able to tackle a problematic variant.
The EU recently agreed to buy up to 60m Valneva doses but the UK, which had helped fund the expansion of Valneva’s Scottish factory, backed out of its agreement with the company in September.
If the world needs a vaccine tailored to this new variant, or another future strain, governments, regulators and the WHO will have to decide when to make the switch.
Clive Dix, former interim head of the UK government’s vaccine task force, said it would be important to keep a close eye on how severe the disease became for vaccinated people.
“Unfortunately, the data won’t be generated in the lab, it will be real world data in people,” he said. “If, when, they analyse vaccinated people in South Africa, where it is swirling around, they find they are getting very ill, that’s the alarm bell to actually start making some vaccine — and that would be soon.”
Richard Hatchett, chief executive of the Coalition for Epidemic Preparedness Innovations, said the new variant underscored the need for more Covid vaccine research and development. “It’s of course critical that we continue to get people vaccinated globally . . . but we must also focus effort and resources on improving the current Covid-19 vaccines to make them more effective against multiple variants,” he said.
Antibody treatments
If vaccines become less effective, drugs to treat Covid become even more important.
Rafael Bayarri Olmos, an immunologist and researcher at Copenhagen University Hospital’s Laboratory of Molecular Medicine, said the variant was most likely to threaten the effectiveness of antibody treatments.
The immune protection from vaccines could work against the whole spike protein, but antibody treatments focused entirely on the receptor binding domain where the virus bound to cells, he said. The B.1.1.529 strain has 15 mutations in this area.
“The variant could dent the effectiveness of vaccines but not completely undermine it,” Olmos said. But it could make some antibody treatments “completely non-functional”.
Early analysis by the Bloom Lab at the Fred Hutchinson Cancer Research Institute in Seattle forecast that antibody treatments from AstraZeneca and GlaxoSmithKline are more likely to be able to tackle the new strain than the earlier generation from Regeneron and Eli Lilly.
AstraZeneca said it was testing its treatment but was hopeful it would still work because it included two antibodies that acted in different ways.
Sajid Javid, the UK health secretary, said on Friday that the new variant might have an impact on the effectiveness of “one of the major treatments”: Ronapreve, made by Regeneron.
The New York-based biotech said it was testing its current antibodies and next-generation candidates, one combination of which is already in clinical trials.
Antivirals
The “good news” was that the antivirals used to treat Covid worked in a different way from vaccines, so they were less likely to be affected by mutations in the spike protein, Walton said.
Kin-Chow Chang, a professor at Nottingham university who studies antivirals for respiratory viruses, said the new variant highlighted the need for this type of treatment. He was working on one as a “second line of defence”.
Pfizer and Merck recently reported positive late-stage trial results for their antivirals and the latter has received approval in the UK. Merck on Friday revised down its efficacy data in an analysis of the full results, showing that its treatment reduced the risk of hospitalisation and death by 30 per cent, not 50 per cent.
But pharma companies have not scaled up the production of antivirals to the level that might be required if the new variant really does take off. Merck expects to have 10m courses by the end of the year, with Pfizer set to deliver just 180,000. The companies are sharing their technology with generic manufacturers but they will also take time to gear up.
“It is a good insurance policy, but I don’t think they will be at a scale anywhere near enough,” said UBS’s Leuchten.
Chang said drugmakers were probably “quite calm” about the abilities of their antivirals against new variants — but would still be eager to test.
“The first to have data to show that it works against the latest variant will gain a lot of market recognition,” he said.
Additional reporting by Oliver Barnes in London
https://news.google.com/__i/rss/rd/articles/CBMiP2h0dHBzOi8vd3d3LmZ0LmNvbS9jb250ZW50L2E3YWE0YmQzLTQ0MDUtNDFmOS1iYWNjLTUxZmI0MDE4MTE1NtIBP2h0dHBzOi8vYW1wLmZ0LmNvbS9jb250ZW50L2E3YWE0YmQzLTQ0MDUtNDFmOS1iYWNjLTUxZmI0MDE4MTE1Ng?oc=5
2021-11-26 19:05:36Z
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