Europe’s medicines regulator said on Friday it was reviewing reports of a rare nerve-degenerating disorder in people who received AstraZeneca’s COVID-19 shots, as authorities worldwide aim for transparency over coronavirus vaccine safety.
As part of a regular review of safety reports for AstraZeneca’s vaccine, Vaxzevria, the safety committee of the European Medicines Agency (EMA) is analyzing data provided by the company on cases of Guillain-Barre syndrome (GBS), it said.
The regulator’s heightened attention to the rare immune condition raises new questions about the potential side effects of COVID-19 vaccines after it found last month that the shots of AstraZeneca and US-based Johnson & Johnson may have caused very rare blood clotting cases.
While the EMA has maintained that the benefits of the Anglo-Swedish drugmaker’s cheap and easily transportable vaccine in fighting the deadly pandemic outweigh any risks, several European countries have limited use to older age groups or suspended use altogether.
The regulator has also backed J&J’s vaccine.
The EMA said GBS was identified as a possible adverse event which needed to be specifically monitored during the vaccine’s conditional approval process, adding that it had requested more detailed data on the cases from AstraZeneca.
GBS is a rare neurological condition in which the body’s immune system attacks the protective coating on nerve fibres. Most cases follow a bacterial or viral infection.
The condition has also been linked in the past to vaccinations - most notably to a vaccination campaign during a swine flu outbreak in the United States in 1976, and decades later to the vaccine used during the 2009 H1N1 flu pandemic.
However, researchers have found the chances of developing GBS after vaccination are extremely small.
On Friday, the EMA also said it was looking into reports of heart inflammation with Pfizer-BioNTech’s vaccine, called Comirnaty, and Moderna’s shot. It said there was no indication at present that these cases were due to the vaccines.
Both the Pfizer-BioNTech and Moderna vaccines use new mRNA technology to build immunity.
Last week, the US Centers for Disease Control and Prevention said it had not found a link between heart inflammation and COVID-19 vaccines.
AstraZeneca, Pfizer, BioNTech and Moderna did not immediately respond to a request for comment.