Europe’s regulator upholds AstraZeneca's COVID-19 vaccine amid blood clot reports

Officials noted the clotting predominantly affects those younger than 60 and women

A safety committee for Europe’s regulator confirmed Wednesday that the benefits of AstraZeneca’s COVID-19 vaccine continue to outweigh risks of side effects, after a review of rare and unusual blood clotting reports among vaccinated adults.

"The PRAC [Pharmacovigilance Risk Assessment Committee] has confirmed that overall benefits of the vaccine from AstraZeneca in preventing COVID-19 are well-established and the risks are very rare," said Sabine Straus, chair of the safety committee.

"Based on the current available evidence, specific risk factors such as age, gender, or previous medical history of clotting disorders have not been able to be confirmed as the rare events are seen in all ages and in men and women," said Emer Cooke, executive director of the European Medicines Agency (EMA).


The committee reviewed 62 cases of cerebral venous sinus thrombosis (CVST) and 24 cases of splanchnic vein thrombosis (SVT) through the EU drug safety database. As of March 22, 18 of the cases were fatal, and the cases came mainly from reporting systems in the European Economic Area and the U.K., Straus said. As of April 4, the EU drug safety database received 169 total cases of CVST and 53 cases of SVT amid a backdrop of 34 million vaccinated individuals.

"After extensive discussions within the committee and taking into account the findings of the expert group, our conclusion is that these clotting disorders are very rare side effects of the vaccine," Straus said.

A plausible explanation for the clotting was noted as an immune response to the vaccine, leading to a condition similar to that seen in patients treated with heparin, called heparin-induced thrombocytopenia. Officials noted the clotting predominantly affects those younger than 60 and women, but could not recommend any specific measures to reduce risk.


Cooke urged that vaccinated individuals and health care providers be aware of the signs and symptoms associated with the rare side effects, and the regulator will continue to assess available evidence and issue updated recommendations if necessary. Symptoms to watch for include shortness of breath, chest pain, persistent stomach pain and headaches, blurred vision and skin bruising beyond the injection site.

Straus noted the vaccine’s product information would be updated to reflect the new findings and will be added as an adverse drug reaction to the product information, including warnings.

The briefing marks the second time the safety committee has convened and issued recommendations over AstraZeneca’s COVID-19 vaccine pertaining to blood clot reports after more than dozen mostly European countries temporarily paused vaccinations out of precaution last month.


Meanwhile, the U.K.'s regulatory agency also announced Wednesday that the benefits of the AstraZeneca COVID-19 vaccine continue outweigh its risks, but it said those under age 30 would be offered alternative vaccines due to a rare blood clotting risk, per multiple reports.

The U.K.'s Medicines and Healthcare products Regulatory Agency (MHRA) said evidence of a link between "extremely rare" blood clots and the AstraZeneca COVID-19 vaccine is "stronger but more work is still needed."

Fox News has requested comment from AstraZeneca.