When researchers at the University of Oxford unveiled their COVID-19 vaccine last year, it was hailed as a breakthrough and soon seen as the cornerstone of vaccination campaigns around the world.
The vaccine had critical advantages: It did not require supercold storage, like vaccines by Pfizer-BioNTech and Moderna, and Oxford’s manufacturing partner, AstraZeneca, promised to sell it at cost to make it affordable for all countries.
But it quickly ran into trouble. First there was an embarrassing mix-up during clinical trials, with some volunteers receiving only a half-dose, forcing researchers to reassess their results. Then came concerns that there was insufficient data to show the vaccine worked in people over 60. And finally, last week questions surfaced about its possible link to blood clots.
On Monday, AstraZeneca reported that its vaccine provided strong protection among adults of all ages in a long-anticipated U.S. study, a finding that could move it a step closer to clearance in that country. In the study of more than 32,000 people, the vaccine was 79-per-cent effective at preventing symptomatic cases of COVID-19. There were no severe illnesses or hospitalizations among vaccinated volunteers, compared with five such cases in participants who received dummy shots – consistent with findings from Britain and other countries that the vaccine protects against the worst of the disease.
However, on Tuesday the U.S. National Institute of Allergy and Infectious Diseases said its safety monitoring board raised concerns about the trial data and said AstraZeneca “may have included outdated information from that trial, which may have provided an incomplete view of the efficacy data.” It urged the company to work with the safety board “to review the efficacy data and ensure the most accurate, up-to-date efficacy data be made public as quickly as possible.”
According to the New York Times, an independent panel of medical experts overseeing the company’s vaccine trials in the U.S. said in a letter to federal officials that the company had selected data that was “most favourable for the study as opposed to the most recent and most complete.” The panel said the vaccine’s efficacy may have been between 69 per cent and 74 per cent. “Decisions like this are what erode public trust in the scientific process,” the board said in the letter.
Despite repeated assurances from regulators, including Health Canada, public trust in the vaccine has been badly shaken. A YouGov poll released Monday showed that confidence in the Oxford-AstraZeneca jab had plummeted in France, Germany, Spain and Italy since February and that a majority of people in those countries no longer believed the vaccine was safe.
“I’m not going to risk taking the AstraZeneca vaccine,” said Jane Wilkins, a teacher in Toronto. Her 31-year-old son, Fraser Wilson, developed severe headaches shortly after being vaccinated on Feb. 18 in Poland, where he’s been teaching for the past few months. His condition quickly deteriorated, and he developed blood clots throughout his body, including in his brain. He also suffered a cerebral hemorrhage and underwent multiple operations. His heart stopped three times, and he remains in intensive care in a hospital in Krakow.
Ms. Wilkins said her son had no previous health issues and had just returned from a backcountry skiing trip before his vaccination. “He was perfectly fine until he had the vaccine,” she said. “I have a science background and I’m not an anti-vaxxer at all. I’d take the Moderna one in the blink of an eye. But I’m not going to risk the AstraZeneca one, that’s for sure.”
Medical regulators in Europe and Britain have not found any direct evidence connecting the AstraZeneca vaccine to blood clots. However, the European Medicines Agency has issued a warning about possible links to the rare type of severe clotting Mr. Wilson experienced. There have been at least 25 such cases in Britain and the European Union and 11 deaths.
“We still cannot rule out, definitively, a link between these cases and the vaccine,” EMA executive director Emer Cooke told reporters last Thursday. However, she added that the vaccine’s “benefits in protecting people from COVID-19, with the associated risks of death and hospitalization, outweigh the possible risks.”
Andrew Pollard, who leads Oxford’s vaccine project, has insisted that all the regulatory reviews have demonstrated the vaccine is safe and effective. He pointed to rising numbers of COVID-19 cases across Europe and added: “Real-world data shows the clear impact of the vaccine on public health – with far fewer cases and hospitalizations from coronavirus in those who have been vaccinated.”
But restoring public faith in the vaccine won’t be easy. More than 20 countries stopped using it last week after 40 cases involving various types of blood clots were reported in Europe. While most governments resumed vaccinations after the EMA’s statement Thursday, a handful have not, including Norway, Denmark and Sweden. French health officials caused more confusion by advising that the vaccine should only be used in people over 55 because the blood clot cases involved younger people; that contradicted their advice in February, which restricted it to those under 65 because of the lack of data on older people.
“I think all the events over the past few days have done a bit of damage, not just with leaving people unprotected against COVID-19, who would otherwise have been vaccinated, but also these longer-term consequences of increased hesitancy,” said Michael Head, a senior research fellow in global health at the University of Southampton. “We probably will see, certainly in the very short term, increased hesitancy.”
There’s also a growing sense that the vaccine has become a political target because of its origins. The British government provided £88.1-million ($152.8-million) to its development, and Prime Minister Boris Johnson touted “the Oxford vaccine” as a great British success.
That appears to have irked some people in the EU, where Brexit remains a sensitive issue. In January, French President Emmanuel Macron took a swipe at the AstraZeneca vaccine by suggesting – incorrectly – that “everything points to thinking it is quasi-ineffective on people older than 65, some say those 60 years or older.” EU officials are also furious that while AstraZeneca has committed 100 million doses to the U.K., it slashed its deliveries to the EU. At one point, Brussels threatened to revoke a key Brexit agreement because of the supply issue, and officials are still considering a ban on vaccine exports to the U.K.
Meanwhile, people in Britain have become even more supportive of the vaccine. “Because it’s seen as a sort of British thing, I get the feeling that people feel like the EU are being a bit funny about it all and they are stoically having it,” said Simon Opher, the lead doctor at the community vaccination centre in Dursley, England, which uses the AstraZeneca vaccine for most of its roughly 1,000 daily vaccinations. “It actually goes against what’s been happening in modern times, which is people get very scared very easily. [Britons] seem to be going, ‘No, we think it’s all right.’”
Dr. Head said the political wrangling is unproductive. “The AstraZeneca vaccine has been a bit of a political football for the past few weeks, and I don’t really quite understand why,” he said. “But what we can say is that along with the Pfizer, Moderna and Johnson & Johnson vaccines, it is safe and effective and it really doesn’t matter which vaccine you get as long as people go and join the queue when they are able to.”
With files from the Associated Press
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