EU Data Show Astra Shot Benefit Varies by Age, Virus Spread
(Bloomberg) -- The European Union’s drug regulator issued a new analysis of AstraZeneca Plc’s Covid-19 vaccine that’s likely to reinforce the decision of some governments not to use it on younger people.
The European Medicines Agency said in the updated analysis that the benefits of the shot outweigh the risks. But the research also showed that the balance strongly depends on both age and how much virus is circulating in the population.
At a medium daily infection rate -- defined as 401 cases per 100,000 residents -- the vaccine would prevent 37 people aged 20-29 per 100,000 from going to the hospital with Covid, but probably result in 1.9 cases of rare blood clots in the same group. For people over 80, the results are far different: preventing 332 hospitalizations with fewer than 1 clot case.
If virus spread is low, the risk of side effects outweighs potential prevention of death or ICU admission in people under the age of 50, the review found. Still, the vaccine protected against hospitalization.
A number of EU countries have already limited their use of the Astra shot, with most only giving it to those aged 60 and older. That move now appears more justified based on the new review by the EMA.
The regulator said it’s too soon for a broad change to the recommendation on the vaccine, however, and that there’s not enough evidence for a full assessment of the shot’s benefits and risks. Peter Arlett, the EMA’s head of analytics, said the agency must examine all scenarios.
For now, the risk-benefit analysis should probably focus on medium or high infection rates, said Sam Fazeli, an analyst with Bloomberg Intelligence. That calculus will change if the pandemic recedes, he said.
“Once we have the disease under control, then I can’t see a room for this vaccine as case rates fall,” Fazeli said. “For example, if a place like Israel now needs a booster vaccine, or when the U.K. gets to the same point, then you would not use this vaccine, assuming the rare side effects are not just after the first dose.”
The EMA said it was also monitoring the messenger RNA vaccines for any similar reactions and couldn’t yet determine whether there was any reason why more blood clots had occurred in the adenovirus vaccines created by Astra and Johnson & Johnson.
Marco Cavaleri, head of the EMA’s vaccines strategy, said they were discussing the issue with any potential developers using the same technology.
“We don’t know yet what is the mechanism behind these rare events and we are right now in the process of starting a number of investigations that hopefully will clarify it the soonest,” said Cavaleri. “We are looking at all the platform technology in order to understand whether any of them could be associated with the same rare events.”
Despite the limits on Astra usage, European Commission President Ursula von der Leyen said earlier on Friday that the EU vaccination campaign is on track and the bloc will meet a key goal in July.
She said she’s “confident” the EU will have enough doses to vaccinate 70% of adults that month. The bloc’s inoculation efforts have stepped up after a faltering start, and some member states are starting to loosen restrictions that were aimed at slowing the spread of the virus.
Separately on Friday, the EMA said it approved plans to ramp up production capacity at a Pfizer Inc. plant in Puurs, Belgium by 20%. The regulator also approved a new filling line at a Moderna site in Spain.
Pfizer and its partner BioNTech SE have become increasingly central to the EU’s Covid vaccination goals -- not only this year but into the future. The partners boosted planned deliveries for this quarter after shortfalls from rival vaccine maker AstraZeneca Plc.
The commission is also ordering as many as 1.8 billion additional doses through 2023 as governments seek to organize booster shots, vaccines for children and potentially also next-generation shots that will work against future virus variants.
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