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The Pharmacovigilance Risk Assessment Committee (PRAC) of the European Medicines Agency (EMA) is investigating cases of thromboembolic events related to AstraZeneca’s COVID-19 vaccine, but says the benefits currently still outweigh risks.
As of March 10, 30 cases of thromboembolic events had been reported among nearly 5 million people vaccinated with the AstraZeneca vaccine in the European Economic Area, which includes European Union (EU) countries as well as Iceland, Liechtenstein, and Norway.
“The number of thromboembolic events in vaccinated people is no higher than the number seen in the general population,” EMA said in statement.
The Danish Health Authority has paused its vaccination campaign with the AstraZeneca vaccine as a precautionary measure while they investigate reports of blood clots in people who received the vaccine, including one individual who died.
Some other European countries have also temporarily stopped using the AstraZeneca vaccine based on reports of blood clots.
Thailand’s Prime Minister Prayut Chan-o-cha has canceled plans to publicly get the AstraZeneca vaccine today, according to a report by CNN .
EMA emphasizes that there is currently “no indication that vaccination has caused these conditions, which are not listed as side effects with this vaccine.”
The most common side effects with AstraZeneca’s COVID-19 vaccine are typically mild to moderate and improve within few days after administration.
“The position of EMA’s safety committee PRAC is that the vaccine’s benefits continue to outweigh its risks and the vaccine can continue to be administered while investigation of cases of thromboembolic events is ongoing,” EMA said.
No Specific Issue With Austria Batch
EMA also said this week that a preliminary view by PRAC suggests “no specific issue” with a batch of AstraZeneca’s COVID-19 vaccine used in Austria that led the country to stop using it.
The Austrian national competent authority suspended the use of AstraZeneca COVID-19 batch number ABV5300 after a person was diagnosed with multiple blood clots and died 10 days after vaccination, and another was hospitalized with pulmonary embolism after being vaccinated but is now recovering.
As of March 9, EMA had received two other reports of thromboembolic events associated with this batch.
“Although a quality defect is considered unlikely at this stage, the batch quality is being investigated,” EMA said. They emphasize, however, that there currently is no indication that receiving a vaccine from this particular batch caused these conditions, which are not listed as side effects with this vaccine.
Batch ABV5300 contains one million doses and was delivered to 17 EU countries (Austria, Bulgaria, Cyprus, Denmark, Estonia, France, Greece, Iceland, Ireland, Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Poland, Spain, Sweden). As of March 9, Estonia, Latvia, Lithuania, and Luxembourg have stopped using this batch.
EMA said that PRAC’s “accelerated” review of thromboembolic events associated with AstraZeneca’s COVID-19 vaccine is being carried out in the context of a safety signal, which is information on a “new or incompletely documented adverse event that is potentially caused by a medicine and that warrants further investigation.”
The US Food and Drug Administration (FDA) has not yet approved the AstraZeneca vaccine, and declined to comment at this time. An additional clinical trial to support the FDA application for emergency use authorization of the AstraZeneca vaccine is ongoing.