Mar 14, 2021 - Health

AstraZeneca: No evidence of increased blood clot risk from COVID vaccine

A member of school staff receives the vaccine for COVID 19 by AstraZeneca on CUS Turin University Sports Center on March 14, 2021 in Turin, Italy.

A member of school staff receives the vaccine for COVID 19 by AstraZeneca on CUS Turin University Sports Center on Sunday in Turin, Italy. Photo: Stefano Guidi/Getty Images

AstraZeneca announced Sunday a comprehensive review has found "no evidence" that its COVID-19 vaccine causes an increased risk of blood clots.

Why it matters: Authorities in Ireland, the Netherlands, Denmark, Norway and Iceland have paused administering the vaccine because of clotting concerns, per Reuters.

  • Austria suspended its AstraZeneca rollout while authorities investigated the death of one person who had received a dose, per Reuters.

What they're saying: AstraZeneca said in a statement that it had conducted a "careful review of all available safety data of more than 17 million people vaccinated in the European Union" and the U.K.

  • It showed "no evidence of an increased risk of pulmonary embolism, deep vein thrombosis (DVT) or thrombocytopenia, in any defined age group, gender, batch or in any particular country," the company said.
  • There have been 15 events of DVT and 22 events of pulmonary embolism reported across this region among those given the vaccine, per AstraZeneca.
  • "This is much lower than would be expected to occur naturally in a general population of this size and is similar across other licensed COVID-19 vaccines," it noted.
"Furthermore, in clinical trials, even though the number of thrombotic events was small, these were lower in the vaccinated group. There has also been no evidence of increased bleeding in over 60,000 participants enrolled."

Of note: European Medicines Agency is investigating incidents of blood clots concerning AstraZeneca's coronavirus vaccine, developed with Oxford University.

  • But the agency has said the benefits "currently still outweigh risks."

The big picture: AstraZeneca has been authorized for use in the EU and also by the World Health Organization, paving the way for the COVAX initiative that's designed to ensure that every country has access to COVID-19 vaccines.

  • The company is expected to file for U.S. approval later this month or early April, according to Reuters.

Editor's note: This article has been updated with new details throughout.

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