AstraZeneca Plc’s vaccine for COVID-19, once expected to be a mainstay of protection for much of the world, remains shrouded in controversy as more countries limit its use even as scientists warn of the need for governments to tread carefully.
The Netherlands joined a growing list of about a dozen places, including northern Italy and Ireland, moving to suspend the shot over concerns about possible side effects from two batches. While regulators from Europe to Asia said there was no indication of any direct link with the vaccine, reports of serious blood clotting after inoculation triggered a spate of suspensions stretching as far as Thailand.
The safety scare emerged against a backdrop of supply woes, and continue a drumbeat of bad news that started with questions about its initial trials and now extends to its potential faltering efficacy against a novel variant. Even as some countries suspend its use, others like the US are moving to protect their own stockpiles, blocking efforts to redistribute the shot’s supply to places with urgent needs.
Astra has defended the vaccine, saying in a Sunday statement that more than 17 million doses have been administered in Europe and U.K., with no evidence that the shot increased the risk of blood clots. As of March 8, there have been 15 reports of clots in the legs, called deep vein thrombosis, and 22 cases where they reached the lungs, known as pulmonary embolism.
Politicians are acting with an abundance of caution but run the risk of hurting global efforts to vaccinate, said Helen Petousis-Harris, a vaccine safety expert at the University of Auckland and a former World Health Organization adviser on vaccine safety.
“You have to be very careful because it’s also sending a message that there could be something very wrong with the vaccine when in fact, it’s very unlikely that there is,” she said. “We’re doing massive mass vaccination campaigns and people get sick all the time. We can’t panic every time it happens. But we also need to take all precaution. And it’s a hard balance.”
The number of events are lower than what would be expected to occur naturally in a general population of that size, AstraZeneca’s Chief Medical Officer Ann Taylor said. In studies, participants getting the vaccine had fewer clots than those given placebo.
On Monday, Thailand said it would resume its planned rollout of the shot this week, four days after suspending it, as a medical panel had decided that the vaccine did not lead to clots. Prime Minister Prayuth Chan-Ocha and some of his cabinet members will be receiving it on Tuesday.
The drama keeps Astra at the center of a political storm in Europe, weeks after manufacturing issues first put the two sides into conflict. Meanwhile, the EU is falling further behind the U.K. and the US in vaccinations, creating a political crisis for the bloc’s leaders.
In addition to low yields producing less vaccine than planned, one plant in the Netherlands is still awaiting regulatory approval to deploy doses. The site, owned by the manufacturer Halix, is making the vaccine drug substance for Astra and forms part of both the EU and UK supply chains. Halix did not respond to a request for comment outside of normal business hours.
But the various issues mean Astra will only be able to deliver about 100 million doses to the EU in the first half of the year, it said Friday, about a third of the number originally planned. Thirty million doses are due to be delivered by the end of this quarter, with the rest coming in the next three months.
Even as some governments suspend dosing, they’re moving to protect their supply. Italy made use of a new EU measure to stop Astra from shipping some doses to Australia on March 4, and Prime Minister Mario Draghi hinted on Friday that he’ll do that again if he has to.
“The European Union has taken clear commitments with pharmaceutical companies and we expect they will be respected,” Draghi said. “We have taken some strong decisions against companies which have delayed the deliveries and we will continue to do so.”
The latest developments will do little to encourage take up of the Astra vaccine in the EU, which had already encountered issues in recent weeks in light of the varying efficacy rates, potential loss of protection against new virus variants, and questions on its effectiveness in older adults. Until recently, a number of countries had restricted use of the shot to those aged under 65.
In a March 7 YouGov survey, perceptions in EU countries of the safety of the shot from Astra and the University of Oxford were lower compared with vaccines from Pfizer Inc. and partner BioNTech SE, and Moderna Inc. By contrast, Britons viewed Astra’s as the safest of the three.
The suspensions may further embed negative views, despite the guidance from the European Medicines Agency. The EMA guidance wasn’t enough to convince Ireland to continue with the vaccine and its Health Minister on Sunday recommended temporarily halting the shot.
Support for the vaccine in the developing world, where the relative low price and ability to store the shot without special refrigeration fueled its initial appeal, could also be hurt by suspensions. AstraZeneca has pledged significant supplies to the Covax program, a facility that aims to distribute vaccines equitably around the world.
The UK has administered more than 25 million vaccine doses -- many of those being the Astra shot -- without raising any alarms over clotting.
The Astra vaccine has become an emblem for growing pandemic nationalism as countries race to inoculate populations as quickly as possible. The US has already ordered nearly enough vaccines from the three manufacturers with authorization from the Food and Drug Administration to immunize its adult population twice over.
“We’re going to start off making sure Americans are taken care of, first, but we’re then going to try to help the rest of the world,” President Joe Biden said on Wednesday.
Meanwhile, back in Europe, the EU spent much of the past week in yet another war of words with the U.K. after it accused Britain of blocking vaccine exports. The EU itself has exported millions of doses, though it also has controls it can use to ensure drug companies honor contracts.
“I think there’s an incredible irony with the European Union complaining about other countries being protectionist,” said Mark Eccleston-Turner, a law and infectious disease specialist at Keele University in England. “At the start of this pandemic they were referring to this vaccine as a public good, and then sought to buy up as many doses as they can and put export controls in place.