Clear link between AZ vaccine and rare brain blood clots, EMA official tells the paper

ROME (Reuters) – AstraZeneca’s COVID-19 vaccine has been linked to very rare blood clots in the brain, but the possible causes are still unknown, a senior European Medicines Agency (EMA) official said in an interview published Tuesday .

“In my opinion we can say it now, it is clear that there is a connection with the vaccine. However, we still do not know what causes this reaction, ”Marco Cavaleri, chair of the vaccine evaluation team at the EMA, told Italian daily Il Messaggero when asked about the possible relationship between the AstraZeneca injection and cases of blood clots in the brain. .

Cavaleri added that the EMA would say there is a link, although this week the regulator likely would not be in a position to provide an indication of the age of the individuals to whom the AstraZeneca injection should be given .

He provided no evidence to support his comments.

AstraZeneca was not immediately available for comment. It has previously said that his studies have not found a higher risk of blood clots because of the vaccine.

The regulator has consistently said the benefits outweigh the risks as it examines 44 reports of an extremely rare brain coagulation disease known as cerebral venous sinus thrombosis (CVST) from 9.2 million people in the European Economic Area who have the AstraZeneca vaccine got.

The World Health Organization has also supported the vaccine.

The EMA said last week that its review had not identified any specific risk factors at this time, such as age, gender, or a previous medical history of clotting disorders, for these very rare events. A causal relationship to the vaccine has not been proven, but it is possible and further analysis is continuing, the agency said.

A large proportion of the reported cases involved young and middle-aged women, but this did not lead the EMA to conclude that this cohort was at particular risk from AstraZeneca inclusion.

The EMA is expected to provide an update on its investigation on Wednesday.

Some countries, including France, Germany, and the Netherlands, have discontinued use of the vaccine in younger people while research continues.

Scientists are exploring several possibilities that could explain the extremely rare blood clots in the brain that occurred in individuals in the days and weeks after receiving the AstraZeneca vaccine.

European researchers have put forward one theory that in some rare cases the vaccine elicits an unusual antibody; others are trying to understand if the cases are related to birth control pills.

But many scientists say there is no definitive evidence and it is not clear whether or why the AstraZeneca vaccine would cause a problem not shared by other vaccines targeting a similar portion of the coronavirus.

In a separate interview, Armando Genazzani, a member of the EMA’s Committee for Medicinal Products for Human Use (CHMP), told La Stampa that it was “plausible” that the blood clots were correlated with the AstraZeneca vaccine.