During its April 2021 meeting, the Pharmacovigilance Risk Assessment Committee (PRAC) of the European Medicines Agency (EMA) concluded on very rare cases of unusual blood clots with low blood platelets reported with Vaxzevria (formerly COVID-19 Vaccine AstraZeneca) and started reviewing a safety signal of capillary leak syndrome in patients vaccinated Vaxzevria. Furthermore, the PRAC is also investigating thromboembolic events reported following vaccination with COVID-19 Vaccine Janssen.
PRAC conclusion on very rare cases of unusual blood clots with low blood platelets with Vaxzevria (AstraZeneca’s COVID-19 vaccine)
EMA’s safety committee (PRAC) has concluded that unusual blood clots with low blood platelets should be listed as very rare side effects of Vaxzevria (formerly COVID-19 Vaccine AstraZeneca).
In reaching its conclusion, the committee took into consideration all currently available evidence, including the advice from an ad hoc expert group.
EMA is reminding healthcare professionals and people receiving the vaccine to remain aware of the possibility of blood clots combined with low levels of blood platelets occurring very rarely within 2 weeks of vaccination.
For more information see EMA’s public health communication.
PRAC reviews signal of capillary leak syndrome with Vaxzevria (AstraZeneca’s COVID-19 vaccine)
PRAC has started a review of a safety signal to assess reports of capillary leak syndrome in people who were vaccinated with Vaxzevria (formerly COVID-19 Vaccine AstraZeneca).
Five cases of this very rare disorder, characterised by leakage of fluid from blood vessels causing tissue swelling and a drop in blood pressure, were reported in the EudraVigilance database.
At this stage, it is not yet clear whether there is a causal association between vaccination and the reports of capillary leak syndrome. These reports point to a ‘safety signal’ - information on new or changed adverse events that may potentially be associated with a medicine and that warrants further investigation.
PRAC will evaluate all the available data to decide if a causal relationship is confirmed or not. In cases where a causal relationship is confirmed or considered likely, regulatory action is necessary in order to minimise the risk. This usually takes the form of an update of the summary of product characteristics and the package leaflet.
EMA will further communicate on the outcome of the PRAC’s review.
PRAC investigating thromboembolic events after vaccination with COVID-19 Vaccine Janssen
PRAC has started a review of a safety signal to assess reports of thromboembolic events (formation of blood clots, resulting in the obstruction of a vessel) in people who received COVID-19 Vaccine Janssen.
Four serious cases of unusual blood clots with low blood platelets have been reported post-vaccination with COVID-19 Vaccine Janssen. One case occurred in a clinical trial and three cases occurred during the vaccine rollout in the USA. One of them was fatal.
COVID-19 Vaccine Janssen is currently only used in the USA, under an emergency use authorisation. COVID-19 Vaccine Janssen was authorised in the EU on 11 March 2021. The vaccine rollout has not started yet in any EU Member State but is expected in the next few weeks. These reports point to a ‘safety signal’, but it is currently not clear whether there is a causal association between vaccination with COVID-19 Vaccine Janssen and these conditions. PRAC is investigating these cases and will decide whether regulatory action may be necessary, which usually consists of an update to the product information.
EMA will further communicate once the evaluation has concluded.
More information is available on the EMA website