Oxford/AstraZeneca Covid-19 vaccine should continue to be used, UK researchers say

The Oxford/AstraZeneca Covid-19 vaccine should continue to be used despite its suspension in a number of countries, the UK’s Drug Safety Research Unit (DSRU) has said.

The announcement comes after Denmark, Austria, Iceland, Norway, Germany, and others, suspended the use of the Oxford/AstraZeneca Covid-19 vaccine following reports of blood clots in patients who had been vaccinated.

Whilst a number of people have sadly died due to coagulation following the vaccine, regulatory authorities around the world have not attributed the cause of increased coagulation with the vaccine.

Dr Phil Bryan, the Medicines and Healthcare products Regulatory Agency Vaccines Safety lead said: “It has not been confirmed that the report of a blood clot, in Denmark, was caused by the Covid-19 Vaccine AstraZeneca. The Danish, Norwegian and Icelandic authorities’ action to temporarily suspend use of the vaccine is precautionary whilst they investigate. Blood clots can occur naturally and are not uncommon. More than 11 million doses of the Covid-19 Vaccine AstraZeneca vaccine have now been administered across the UK.”

Events of blood clots were reported earlier in March, following the use of a specific batch (ABV5300) of the Oxford/AstraZeneca Covid-19 vaccine. The batch of 1 million doses was distributed to 17 countries, with 22 thromboembolic events having been reported since 9 March.

A note the DSRU makes is that when examining causal association between the thromboembolic events and the vaccine, reports of blood clots have not been greater than the number that would have occurred naturally.

Still, regulatory agencies are taking different approaches to the reported events. Some such as Germany, Denmark, Austria, Iceland and Norway have suspended the use of the Oxford/AstraZeneca vaccine until clear data emerges, whereas the UK MHRA and the European Medicine Agency have said vaccinations should continue.

"It is important to stress that we have are by no means discarding the AstraZeneca vaccine. We are merely stopping using it for the time being. There is strong evidence that the vaccine is both safe and efficacious,” said Søren Brostrøm, director general of the Danish Health Authority. However, The Danish Health Authority and the Danish Medicines Agency have to react promptly to reports from Denmark and other European countries of possible severe side effects. This is a clear indication that the monitoring system works."

"At the same time, it is important to us that the population have confidence in the available vaccines and trust us to vouch for the quality, efficacy and safety of the vaccines in our vaccination programme. Therefore, we are taking immediate action until we have fully investigated whether there is a link between the vaccine and any severe side effects."