EU reviewing Johnson & Johnson vaccine after reports of rare blood clots

The European Union’s drug regulatory agency is looking into cases of blood clots among four individuals who received Johnson & Johnson’s coronavirus vaccine, though a link between the two is not yet clear.

The European Medicines Agency (EMA) said Friday that serious cases of “unusual blood clots with low blood platelets” have been reported in four people who received the Johnson & Johnson inoculation, according to Reuters. 

Three of the cases occurred in the U.S. during the vaccine rollout, while one person who participated in Johnson & Johnson’s clinical trial died from a clotting disorder. 

According to the Centers for Disease Control and Prevention (CDC), roughly 5 million people in the U.S. have already received the Johnson & Johnson’s vaccine. 

The company said in a statement shared with The Hill Friday that it was aware of the reports of blood clots and was working with regulators to review safety data. 

“At present, no clear causal relationship has been established between these rare events and the Janssen COVID-19 vaccine,” Johnson & Johnson said.

“The safety and well-being of the people who use our products is our number one priority,” the vaccine developer added. “We share all adverse event reports about individuals receiving our COVID-19 vaccine, along with our assessment of these reports, with health authorities in compliance with regulatory standards.”

The reports come as there has already been widespread concern on blood clots reported in individuals who received the AstraZeneca vaccine, which has not been federally authorized for emergency use in the U.S.

An EMA safety committee on Wednesday said that a “possible link” existed between the AstraZeneca inoculation and rare blood clots, but added that the benefits of receiving the shot outweigh the potential risks. 

The committee said that unusual blood clots with low blood platelets should be listed as very rare side effects of the vaccine, though it placed no new restrictions on the inoculation. 

However, some European countries have imposed limits on the distribution of the AstraZeneca vaccine, including advising young age groups against receiving it. 

Most of the cases of blood clots have been reported among women under the age of 60 within two weeks of receiving the AstraZeneca shot. 

The vaccines from Johnson & Johnson’s and AstraZeneca are two of the four that have been approved in Europe, though rollout of Johnson & Johnson’s single dose has not yet begun across the region.

Updated: April 10 at 10:13 a.m.