The chief executive of AstraZeneca has dismissed suggestions that the UK is being unfairly prioritised for Covid-19 vaccine doses, in a wide-ranging interview revealing “glitches” that have constrained production.
Pascal Soriot offered the deepest insight yet into a scientific process that has been dragged into the political sphere, as leaders in Brussels and several EU capitals voiced anger that Europe will not get the vaccine as quickly as hoped.
He also talked about the “one-dose” strategy and the efficacy of the vaccine against new variants. Here is what we learned from Soriot’s comments, given to Italian newspaper La Repubblica.
Why are EU leaders angry?
The EU ordered 80m doses of AstraZeneca’s vaccine by the end of March but the Anglo-Swedish company has said it can only deliver 31m doses, with deliveries in the following quarter also likely to be 50% lower.
The escalating row, which comes ahead of a decision on Friday by the European Medicines Agency on whether to approve the vaccine, has even led to suggestions from Brussels that exports of doses from the EU could be banned.
On Wednesday, the European Commission said AstraZeneca had pulled out of talks set for the evening, only for the company to deny that minutes later, insisting the summit was still on.
What does the company say?
AstraZeneca’s contract with the EU is on a “best effort” basis, said Soriot, meaning the company is obliged to produce as much vaccine as it can but is not legally committed to fulfilling the order in the volumes the EU wanted.
However, on Wednesday, European leaders said Soriot had misrepresented the contract and insisted the company had signed an “advance purchase agreement” promising it had enough capacity to deliver the order.
Why have there been delays?
AstraZeneca has suffered production problems at plants that make the vaccine for Europe, particularly at one site in Belgium.
“We are basically two months behind where we wanted to be,” said Soriot.
“[…] The sites that have the lowest productivity in the network are the sites that are supplying Europe,” he added.
The vaccine is made in two separate phases. The first is the “drug substance” – the vaccine itself – made for European distribution at plants in the Netherlands and Belgium. The second is the “drug product”, where the vaccine is taken to plants in Italy and Germany and put into vials to be distributed to different countries and, ultimately, to clinicians.
The production problem, explained Soriot, is with the first “drug substance” phase, the manufacture of the vaccine itself. AstraZeneca uses vast “cell cultures” in batches of up to to 2,000 litres. The virus is injected into the cell cultures and the cells produce the vaccine.
However, some plants produce a much higher yield of vaccine than others, up to three times as much.
Why isn’t the UK affected?
It is, or at least, it was.
“We’ve had also teething issues like this in the UK supply chain,” said Soriot.
The difference, he said, is that the UK signed its contract for 100m doses much earlier. As a result, there has been more time for production problems to be ironed out, meaning vaccine yields are higher.
“So with the UK we have had an extra three months to fix all the glitches we experienced,” he said.
Why did the UK move faster?
Soriot declined to comment on the EU’s timing. But he said that when AstraZeneca began developing the vaccine in tandem with Oxford University, Oxford had already begun working with the UK government on plans for how to distribute the vaccine.
AstraZeneca was able to take Oxford’s processes and scale them up. This headstart is what allowed production glitches to be fixed in the UK in time for the vaccine rollout.
Where glitches persist at European sites, the later signing of the contract means there hasn’t yet been time to fix them.
Can UK doses be diverted to Europe?
In a word, no.
“The UK agreement was reached in June, three months before the European one,” said Soriot.
“As you could imagine, the UK government said the supply coming out of the UK supply chain would go to the UK first. Basically, that’s how it is.”
AstraZeneca’s contract with the EU does raise the possibility that some of the vaccine made in the UK could be supplied to the EU, he said, but only once the contract with the UK government has been fulfilled.
This, said Soriot, is “fair enough”.
Is the “one-dose” strategy sensible?
There has been disagreement over whether the UK was right to adopt a strategy of ensuring as many people as possible get their first dose and wait longer for a second, rather than administering both within a short timeframe.
Soriot said he could not speak for the Pfizer or Moderna vaccines but said the “one-dose” strategy was “absolutely the right way to go” for AZ’s.
The company believes one dose is 100% effective at stopping serious illness and hospitalisation and up to 73% efficient overall. A second dose, he said, would be needed for longer-term immunity.
What about new variants?
Soriot was asked about early signs that some vaccines are not as effective on new variants. The South African variant has been of particular concern. Soriot pointed out that the “neutralisation effect” of Moderna’s vaccine has been shown to be six times lower. Tests are still being done on AstraZeneca’s vaccine but he said it was “logical” to expect reduced efficacy.
However, he said existing vaccines would probably still be able to control the virus enough to prevent serious illness, while the company will continue adapting vaccines to respond to new mutations.