AstraZeneca (AZ) has issued an update on the safety of its COVID-19 vaccine, saying a review showed no evidence of an increased risk of blood clots among people vaccinated with its jab.

In a statement, AZ said that across the EU and UK, there have been 15 events of deep vein thrombosis (DVT) and 22 events of pulmonary embolism reported among people given its vaccine – based on the number of cases the company has received as of 8 March.

AZ added that a ‘careful’ review of all available safety data – including more than 17 million people vaccinated in the EU and UK with its COVID-19 vaccine – has shown ‘no evidence of an increased risk of pulmonary embolism, DVT or thrombocytopenia, in any defined age group, gender, batch or in any particular country.’

The cases reported so far are ‘much lower’ than what would be expected to naturally occur in a general population of this size and is similar to other licensed COVID-19 vaccines, according to AZ.

“Around 17 million people in the EU and UK have now received our vaccine, and the number of cases of blood clots reported in this group is lower than the hundreds of cases that would be expected among the general population,” said Ann Taylor, chief medical officer of AZ.

“The nature of the pandemic has led to increased attention in individual cases and we are going beyond the standard practices for safety monitoring of licensed medicines in reporting vaccine events, to ensure public safety,” she added.

AZ added that there are also no confirmed issues related to any batch of the vaccine used across Europe or globally.

The company said that additional testing has and is being conducted by itself and independently by European health authorities – with none of these retests showing ‘cause for concern’.

‘The safety of the public will always come first. The company is keeping this issue under close review but available evidence does not confirm that the vaccine is the cause. To overcome the pandemic, it is important that people get vaccinated when invited to do so,’ AZ said in a statement.

A number of countries have suspended the use of AZ’s vaccine after the reports of blood clot issues, including Ireland, Denmark, Norway, Iceland and the Netherlands.

In response to the Irish authorities decision to halt use of the AZ COVID-19 vaccine, the UK Medicines and Healthcare products Regulatory Agency’s (MHRA) vaccines safety lead Phil Bryan said: “We are closely reviewing reports but given the large number of doses administered, and the frequency at which blood clots can occur naturally, the evidence available does not suggest the vaccine is the cause.”

“People should still go and get their COVID-19 vaccine when asked to do so,” he added.