|Articles|April 20, 2021

EMA Finds Possible Link With Johnson & Johnson Vaccine and Rare Blood Clots, Benefit-Risk Remains Positive

Author(s)Killian Meara

The committee stressed that the events are exceedingly rare, and that the vaccine's benefits outweigh the potential risks.

Update 4/20/21: Johnson & Johnson announced on Tuesday that they will resume the rollout of their COVID-19 vaccine In Europe, following a statement from the European Medicines Agency (EMA) citing the benefit-risk ratio for the shot was still positive. The company will now start sending shipments of the vaccine to reach their agreement of 50 million doses, which was agreed upon earlier in April.

The original article was published on 4/20/21.

On Tuesday, the European Medicines Agency safety committee (PRAC) came to the conclusion that the COVID-19 vaccine created by Janssen Pharmaceuticals, a company of Johnson & Johnson, has a possible link with rare cases of unusual blood clots with low blood platelets, and that a warning should be added to the products information.

However, they added to their statement that the warning should include how the events are extremely rare.

The committee took into consideration all of the evidence that is currently available, including 8 reports of serious cases of unusual blood clots associated with low levels of blood platelets from the United States.

The PRAC mentioned that the majority of documented events occurred at unusual sites such as in veins in the brain, the abdomen and in arteries, together with low levels of blood platelets and sometimes bleeding.

Of the known cases, all occurred in persons under the age of 60, the majority being women, within 3 weeks of vaccination. No specific risk factors have been determined at this point.

One explanation that has been put forward is that an immune response causes the blood clots and low blood platelets, which can lead to a condition similar to one sometimes seen in patients treated with heparin, called heparin induced thrombocytopenia (HIT).

The committee stressed the importance of immediate treatment by medical professionals, to aid in a quick recovery and avoid any potential complications.

The EMA will continue to monitor the vaccine’s safety and efficacy, and still hold that the shot’s benefits far outweigh the risk for any potential side effects.

Over 7 million people in the US have received the Janssen vaccine as of April 13th.


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