The EU's drug regulator has said it is investigating possible side effects of mRNA Covid-19 vaccines produced by Pfizer and Moderna.
In an official safety update, the European Medicines Agency (EMA) said it was examining three medical conditions reported by patients, including a small number of incidences of skin rashes and two kidney disorders.
These are erythema multiforme, a form of allergic skin reaction; glomerulonephritis or kidney inflammation; and nephrotic syndrome, a renal disorder characterised by heavy urinary protein losses.
While traditional vaccines give the body a weakened or inactive virus to cause the production of antibodies, mRNA vaccines make cells produce a protein that starts an immune response.
Pfizer, which is by far the biggest supplier of Covid-19 vaccines to the EU, has a not yet commented on the reports.
The EMA did not give details on Wednesday on how many cases of these conditions were recorded, but said it had requested more data from the companies.
It did not recommend changes to the labelling of the vaccines.
A little over 43.5 million doses of Moderna's vaccine have been administered in the EU as of July 29, the EMA said. This compares with more than 330 million administered doses of the Pfizer shot, which was developed with Germany's BioNTech.
Last month, the EMA found a possible link between very rare heart inflammation and the mRNA vaccines. However, the European regulator and the World Health Organisation have stressed that benefits from these vaccines outweigh any risks.
Meanwhile, the US Food and Drug Administration said on Thursday that it has not seen evidence to suggest that the Pfizer and Moderna vaccines were causing additional side effects.
“The FDA is aware of the EMA report. To date, we have not seen any safety signals for the adverse events identified in the report,” FDA spokeswoman Abigail Capobianco said. “[We are] monitoring the safety of authorised Covid-19 vaccines through both passive and active safety surveillance systems.”