European Medicines Agency identifies blood clots as ‘very rare’ side effect of Johnson & Johnson vaccine

The European Medicines Agency (EMA) has said that the COVID vaccine manufactured by Johnson & Johnson's subsidiary Janssen has possible links to rare blood clot incidents, but that these risks are outweighed by the vaccine's benefits.

Following the suspension of the use of the vaccine in the US last week, and its subsequent investigation, the EMA's safety committee (PRAC) has concluded that "a warning about unusual blood clots with low blood platelets should be added to the product information for COVID-19 Vaccine Janssen”.

The EMA researched all available evidence, it said, including eight reports from the US regarding serious cases of unusual blood clots, occurring amongst the seven million people that received the vaccine.

"All cases occurred in people under 60 years of age within three weeks after vaccination, the majority in women. Based on the currently available evidence, specific risk factors have not been confirmed", the organisation commented.

However, it reiterated, "COVID-19 is associated with a risk of hospitalisation and death. The reported combination of blood clots and low blood platelets is very rare, and the overall benefits of COVID-19 Vaccine Janssen in preventing COVID-19 outweigh the risks of side effects".

The Janssen vaccine was reported to have arrived in the EU last week. Malta has reserved 250,000 doses of the vaccine, and the EU is expected to receive 55 million doses of the single-shot vaccine by June.

In recent months, the vaccine produced by AstraZeneca was roiled in controversy after a small number of fatal blood clots were reported in recipients. 

Indeed, the EMA identifies that the "cases reviewed [connected to Janssen's vaccine] were very similar to the cases that occurred with the COVID-19 vaccine developed by AstraZeneca, Vaxzevria".