The European Medicines Agency (EMA) said Tuesday it found a “possible link” between the Johnson & Johnson (J&J) COVID vaccine and very rare blood clots, but concluded the vaccine’s benefits still outweigh the risks.
J&J had delayed the vaccine’s rollout in the EU after concerns about blood clots led U.S. regulators to call for a pause. The company said Tuesday it will resume shipment of the vaccine, distributed under its Janssen subsidiary, in the EU, Norway and Iceland.
In reaching its conclusion, the committee said it took into consideration all currently available evidence including eight reports from the U.S. of serious cases — one of which was fatal — of unusual blood clots. All cases occurred in people under 60, and all occurred within three weeks after vaccination. The majority were women.
PRAC noted blood clots linked to the J&J vaccine are occuring in unusual parts of the body, such as veins that drain blood from the brain (cerebral venous sinus thrombosis, or CVST), abdomen (splanchnic vein thrombosis) and arteries.
The patients studied also had abnormally low levels of blood platelets, a condition normally linked to bleeding, not clotting.
The cases reviewed were similar to the rare blood clot cases that occurred with the COVID vaccine developed by AstraZeneca, now called “Vaxzevria.” Earlier this month, the EMA announced it had reached a similar conclusion about the AstraZeneca vaccine, and recommended a warning label, but no other restrictions.
Vaccine may trigger immune response that can cause blood clots
The EMA noted one plausible explanation for the combination of blood clots and low blood platelets is an immune response leading to a condition similar to heparin-induced thrombocytopenia, a condition seen in patients treated with the drug heparin.
Scientists in Norway and Germany who studied blood clots after the AstraZeneca vaccine have suggested that some people are experiencing an abnormal immune response causing them to form antibodies that attack their own platelets after being vaccinated.
It’s not yet clear if there might be a similar mechanism with the J&J vaccine, the AP reported. But J&J and AstraZeneca vaccines, as well as a Russian COVID vaccine and China’s, are made with the same technology.
“Suspicion is rising that these rare cases may be triggered by the adenovirus component of the AstraZeneca and J&J vaccines,” said Eleanor Riley, a professor of immunology and infectious diseases at the University of Edinburgh. Riley said that while more data is needed, “it remains the case that for the vast majority of adults in Europe and the USA, the risks associated with contracting COVID-19, far far outweigh any risks of being vaccinated.”
According to the Centers for Disease Control and Prevention (CDC), the highest at-risk age group for severe COVID is people over 85, followed by people over 65 — with eight out of 10 COVID deaths occurring among adults 65 and over.
U.S. pause of J&J vaccine still in place
The U.S. Food and Drug Administration earlier this month advised states to suspend the use of J&J’s shot “out of an abundance of caution.” In a joint statement with the CDC, the agencies said the Advisory Committee on Immunization Practices (ACIP) was reviewing clinical data gathered on six women, one who died, between the ages of 18 and 48 years who developed blood clots after receiving the single-dose J&J vaccine.
On April 14, the ACIP held an emergency meeting to vote on whether to lift the pause on J&J’s vaccine or change recommendations for its use. As The Defender reported, the ACIP postponed the vote, extending the pause pending further analysis of data relating to blood clots. The ACIP said it would reconvene for a vote in one week to 10 days.
That same day, J&J revealed two more cases of blood clots — one that occurred in a 25-year-old man who suffered a cerebral hemorrhage during a clinical trial and another case of deep-vein-thrombosis in a 59-year-old woman.
The CDC’s advisory panel is scheduled to meet April 23 to discuss J&J’s vaccine, whether the pause should be lifted, and if so, what recommendations for use should be implemented.
Last week, South Africa suspended J&J in the wake of the U.S. pause, and countries including Italy, Romania, the Netherlands, Denmark and Croatia put their J&J doses in storage pending the review.