AstraZeneca vaccine likely to combat new Covid variants

People wait for doses of the AstraZeneca vaccine at a vaccination centre in Seixal, Portugal, on Monday

Credit: Pedro Nunes/Reuters

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The AstraZeneca vaccine is likely to work against new Covid variants, researchers have said following trials in the US and South America.

The latest results show the jab is 79 per cent effective at preventing the virus and offers 100 per cent protection against severe disease. The results are similar to British trial data, and also real-world effectiveness. 

Crucially, the new trial was conducted during a period when worrying new variants were sweeping through populations and demonstrates that it is just as effective. 

The UK Covid variant is now thought to account for around 30 per cent of all cases in the US, while the Brazilian variant is spreading rapidly in South America.

Speaking at a briefing on Monday, Mene Pangalos, the executive vice president of bioPharmaceuticals R&D at AstraZeneca, said: "We are looking at all the variants of concern and we’ll have an analysis of all the different strains.

"But given that this study was conducted much later in terms of timing it’s very encouraging that we’ve got such a high efficacy when there are undoubtedly variants of concern circulating in this study. Also I think it highlights why we believe that, against severe disease, our vaccine will be effective against all variants of concern and we’ve said this consistently."

Some 32,449 people across all age groups took part in the phase three trial in the US, Chile and Peru, with a total of 141 cases of symptomatic Covid reported. The results showed that, among people aged 65 and over, there was 80 per cent protection against developing the virus.

An independent data safety monitoring board (DSMB) also conducted a specific review of blood clotting events, as well as cerebral venous sinus thrombosis (CVST) – a rare type of  the brain blood clot that has been seen several times in Europe. 

The Medicines and Healthcare Products Regulatory Agency (MHRA) is currently conducting an investigation into the death of one Briton who died from CVST shortly after receiving the AstraZeneca jab. The DSMB found no increased risk of thrombosis among the 21,583 participants receiving at least one dose of the vaccine. There were no cases of CVST in the trial.

Sarah Gilbert, professor of vaccinology at Oxford and the co-designer of the vaccine, said the new findings "provide further confirmation of the safety and effectiveness" of the jab.

She added: "In many different countries and across age groups, the vaccine is providing a high level of protection against Covid-19 and we hope this will lead to even more widespread use of the vaccine in the global attempts to bring the pandemic to an end."

Last week, the European Medicines Agency (EMA) ruled that the AstraZeneca vaccine was not causing blood clotting after more than a dozen countries suspended its use.

However there are fears that the debacle has damaged confidence in the jab at a time when Europe is facing a third wave.

According to polling by YouGov, more than half of Germans and 61 per cent of people in France now believe the jab is unsafe. Both Angela Merkel and Emmanuel Macron have been heavily criticised for suggesting it was not safe for older people. 

Over the weekend, the EU moved to block vaccine exports to Britain, suggesting that the vaccine substance produced by the Halix plant in the Netherlands should stay in Europe.

AstraZeneca said it was "incredibly important" that supplies be allowed to move freely, but said the Halix plant only produced a small amount of vaccine which up to now has only been used for clinical trials. 

Ruud Dobber, the executive vice president of the BioPharmaceuticals Business Unit at AstraZeneca, said: "We are highly dependent on our global supply network and as such we are hoping we can have free goods moving from one place to another place.

"Europe is highly dependent on the drug substance coming from the United States. It’s incredibly important that our goods can move from one [area] to another."

AstraZeneca will now submit data to the US Food and Drug Administration and seek emergency approval for use. The US had been waiting for the latest results before considering it.  The company said it had 30 million doses ready to be deployed as soon as it was granted approval.