AstraZeneca vaccine deemed safe by EMA, again

In a Wednesday status update on the European Medicines Agency's (EMA's) ongoing investigation into rare reports of blood clotting problems in people who have received the AstraZeneca COVID-19 vaccine, EMA head Emer Cooke offered reassuring words about the vaccine’s benefit-risk profile.
 
“Two weeks ago, on the 18th of March, we gave an interim update of the assessment and we concluded at the time that the benefits of the AstraZeneca vaccine in preventing COVID-19 -- with its associated risk of hospitalization and death -- outweigh the risk of side effects, and our position has not changed,” said Cooke in Wednesday’s press briefing, which followed an all-day meeting of PRAC, EMA’s safety committee. (RELATED: EMA judges AstraZeneca vaccine safe after blood clot investigation, Regulatory Focus 18 March 2021)
 
On Monday, PRAC called in a team of independent experts to review reported events. Hematologists, neurologists and epidemiologists were among the experts who “looked at possible physiological mechanisms and whether there was any potential underlying risk,” said Cooke.
 
PRAC also sought independent expert review of whether additional data were needed to characterize the events that have been observed and reported. “At present the experts have advised us that they have not been able to identify specific risk factors, including age, gender or previous medical history of clotting disorders for these very rare events,” added Cooke.
 
An earlier PRAC assessment produced a detailed 24 March report on clinical and non-clinical data surrounding any increased risk of thrombotic events. The 50-page document concluded that “there is currently no evidence to suggest an association of thrombotic events with the use of COVID-19 vaccine AstraZeneca.” However, PRAC did note a “signal” for certain rare events involving both clotting and bleeding, though no causal association could be established from available data.  (RELATED: EMA, WHO investigate reported clots with AstraZeneca vaccine, Regulatory Focus 15 March 2021)
 
Ongoing monitoring of individual case reports and Eudravigilance data continues, and PRAC and its expert advisors are working to understand background risk for thromboembolic events in subsets of the population. European countries have taken varying approaches to the reports of thrombotic events, which thus far have not overall risen above the rate seen in the population at large. (RELATED: EMA offers reassurance on AZ vaccine, while some European authorities pause, Regulatory Focus 11 March 2021)
 
In response to a question during the press briefing, Cooke made clear that EMA’s safety monitoring is ongoing: “[W]e continue to evaluate the benefit-risk of a vaccine over its entire life cycle. So that's as long as it's on the market -- forever and ever. So there is no threshold at which we stop unless there was a decision to discontinue the vaccine.”
 
Cooke ended her prepared remarks with the reminder that EMA’s role in evaluating the benefits and risks of a vaccine is to provide the EU member states with the information they need to design and implement their own national vaccination campaigns. “These may and do differ from country to country depending on their individual needs and their circumstances in the country -- issues such as infection rates, priority populations, the availability of vaccines, the pressure on the hospitalization systems and so on -- but our recommendations will be guided by science.”
 
The next update is planned for PRAC’s next plenary meeting, scheduled for 6 through 9 April.
 
 
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