The government will look “very carefully” at concerns the Pfizer-BioNTech coronavirus vaccine’s initial effectiveness is low, the UK’s top government scientist has said.
Israel, which has already given about a quarter of its population a first dose, has warned that it could be as low as 33% effective after the first injection.
However, it has been revealed that it is likely to protect against the more infectious variant of coronavirus that was identified in the UK and has helped drive up cases.
Low initial efficacy may have implications for the UK’s vaccine strategy, which focuses on giving as many people an initial dose before providing the booster jab up to 12 weeks after.
Watch: Pfizer vaccine appears effective against UK variant
Speaking to Sky News, Sir Patrick Vallance, the government’s chief scientific adviser, said between day 10 after the first dose and 21 days after, it was “much more like 89%” efficacy in studies.
However, he warned that “when you get into real-world practice things are seldom quite as good as clinical trials”.
“It probably won’t be as high as that in practice, but I don’t think it’ll be as low as the figures you’ve just given,” he told Sky’s Q&A.
“We need to look at this very carefully, we just need to keep measuring and understanding.”
Later on Wednesday, a Downing Street spokesman insisted the decision to give a second jab after 12 weeks came from available data, which showed the Pfizer-BioNTech vacine is 89% effective in protecting against COVID-19 between 15 and 21 days after the first dose.
“But again I would point to what the medical experts and scientific advisers have said previously about the fact that once you’ve received the first dose, it takes some time for your body to build up immunity,” the spokesman said.
“You don’t have immunity immediately after taking the first dose, but again, we’ve set out why we are doing the dosages in the way we are, and that’s to protect as many people as possible as quickly as possible.”
Data ‘insufficient’ to say UK vaccine policy is wrong
Reuters reports that Israel is working with Pfizer to provide data on the vaccine.
Professor Stephen Evans, professor of pharmacoepidemiology at London School of Hygiene and Tropical Medicine, said the reports from Israel are “insufficient to provide any evidence that the current UK policy in regard to delaying the second dose of vaccines is in any way incorrect”.
“It is not sensible to compare efficacy derived from an observational study of this type which is subject to many biases, with the efficacy derived from randomised trials,” he said.
The professor added that more robust data should be gathered before a change in policy is made to how vaccine doses are given out.
Vaccines ‘not doing enough heavy lifting’
Sir Patrick warned that coronavirus cases need to drop before the government thinks of easing the lockdown.
He said vaccines are not yet doing enough “heavy lifting” to give the government cause to lift restrictions but said there is “light at the end of the tunnel”.
Officials hope to give the most vulnerable to COVID-19 – some 15 million people – a vaccine dose by 15 February, and there are reports the government wants to ease restrictions by Easter.
More than 4.2 million first doses have been given out, and 450,000 second jabs have been provided.
“The advice at the moment is vaccines are not going to do the heavy lifting for us at the moment, anywhere near it,” Sir Patrick said.
“This is about, I’m afraid, the restrictive measures which we’re all living under and carrying on with those.
“The numbers are nowhere near where they need to be at the moment, they need to come down quite a lot further – we need to make sure we stick with it.
“You go for a walk in the park or something, life looks normal; you go for a walk in a hospital, if you work in a hospital, you will see life not looking normal at all.
“This is a really difficult, dangerous situation we’re in, and we need to get the numbers down, so I don’t see a release of these measures as being a sensible thing to do in the short term.”
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