AstraZeneca’s COVID-19 vaccine has rarely been out of the news – and the headlines show no signs of abating. Jacqui Wise explains how miscommunication and politics created a nightmare for both the company and the global vaccination effort
CREDIT: This is an edited version of an article that originally appeared on The BMJ
Hailed as a ‘vaccine for the world’, with its low price and easy storage requirements, AstraZeneca’s vaccine candidate has faced a string of setbacks in 2021, with questions over effectiveness, possible side-effects, and long running disputes about supplies.
It’s not clear why the Anglo-Swedish company and its vaccine have been singled out for so much criticism, but poor communication seems to be at the heart of the problem. Martin McKee, professor of European public health at the London School of Hygiene & Tropical Medicine, says, “This is a company that has taken an innovative product to market in record time but has mishandled communications at every step. Trust and confidence are so important for vaccines—you can’t divorce the two.”
AstraZeneca’s latest crisis is also possibly its biggest so far; its vaccine has been linked to thrombosis, as well as a rare type of blood clot in the brain called cerebral venous sinus thrombosis, with a number of episodes in younger women.
The vaccine was authorised for use in Europe at the end of January, and started to be used more widely in February. On 7 March Austrian authorities announced that they were investigating a death that was possibly vaccine-related. A few days later Denmark and Norway were also investigating reports of blood clots, and a death, after vaccination. On 15 March Germany suspended its use of the vaccine, followed swiftly by several other countries.
The European Medicines Agency (EMA) and the World Health Organization say that the vaccine’s benefits outweigh any risks; the EMA undertook an in-depth review of the issue and, while acknowledging a ‘possible’ link to blood clots that should be listed as ‘very rare’ side effects, on 7 April it confirmed that the ‘overall benefit-risk remains positive’ for the vaccine’s continued use. The cause of the clots is still unknown, with research ongoing.
In the UK, which has ordered 100m doses of AstraZeneca vaccine, the Joint Committee on Vaccination and Immunisation advised, on 7 April, that people aged under 30 should be offered alternative vaccines where available—even though the Medicines and Healthcare Products Regulatory Agency (MHRA), which conducted the UK review of the evidence, emphasised that it was ‘not recommending new age restrictions in COVID-19 AstraZeneca vaccine use’.
The MHRA said that, up to 31 March, 79 thrombosis events with low platelets had been reported from over 20m doses of the vaccine administered. Among these reported cases, 19 people have died; the overall risk of these blood clots is about four people in every million who receive the vaccine.
Ines Hassan, senior policy researcher with the Global Health Governance Programme at the University of Edinburgh, sees a positive in the way the issue is being investigated. “The scrutiny from regulators and pharmacovigilance experts shows that the system and safety monitoring procedures are working as they should,” she says.
What’s not helpful is how it’s been communicated. Whether from different regulators, government officials, academics, or the media, Hassan tells The BMJ, “It is clear that the mixed messaging from these different stakeholders has caused confusion among the general public, and it has already led to increased vaccine hesitancy in some parts of Europe, among other regions.”
In the US
Adding salt to the wound, AstraZeneca had, simultaneously but separately, faced criticism in the United States. In a 22 March press release the company announced the long-awaited results of a key US trial – one that it hoped would finally win emergency use approval for the vaccine from the US Food and Drug Administration (FDA). The FDA has been cautious around the AstraZeneca vaccine; nearly four months since the UK approved it, the FDA has yet to issue approval for its use in the US despite approving vaccines from Pfizer, Moderna and Johnson and Johnson (Janssen).
In the March announcement AstraZeneca said that the results showed a 79% efficacy in preventing symptomatic disease. Hours later, however, the US National Institutes of Health (NIH) took the unusual step of issuing a midnight statement saying that its data and safety monitoring board had “expressed concern that AstraZeneca may have included outdated information from that trial, which may have provided an incomplete view of the efficacy data.”
AstraZeneca says that the agreed cut-off point for data was 17 February, as publicised in its initial release. In response to the NIH, within 48 hours, it added more recent data and revised the efficacy down to 76%. The US chief medical adviser, Anthony Fauci, called this an “unforced error” on AstraZeneca’s part; speaking on Good Morning America he said, “It was not necessary—if you look at it, the data really are quite good, but when they put it into the press release it wasn’t completely accurate.”
Martin McKee says that it is, “completely unprecedented that a data monitoring committee would say that what you said in a press release was not accurate. It’s so basic that you don’t issue contradictory information. What on earth was going on there that they didn’t check?”
However, Peter English, a retired consultant in communicable disease control, former editor of Vaccines in Practice magazine and immediate past chair of the BMA’s public health medicine committee, has sympathy for the company. “It seems like it was an attack on the company, and not founded on science,” he says. “AstraZeneca had stated in advance in their protocol the time period, so [they] couldn’t cherry pick the data. If they had done it other way round they would rightly have been criticised.”