BRUSSELS, Belgium - The European Union's drugs regulator has concluded that blood clots are a very rare side effect of Johnson & Johnson's COVID-19 vaccine and an advisory should be added to the product label, but the benefits of the single-shot vaccine still outweigh the risks.
The European Medicines Agency (EMA) said it made its assessment based upon data from the U.S., which has reported nine instances of individuals developing blood-clots, including one death, among seven million recipients of the J&J vaccination, the Wall Street Journal reported.
The cases are currently under investigation and more might emerge, a senior U.S. health official said.
To date, the cases have involved blood clots forming in a major vein draining the brain, with patients presenting with abnormally low levels of blood platelets, or in some cases, bleeding.
Last week, the US Food and Drug Administration and the Centers for Disease Control and Prevention recommended suspending the use of the vaccine. One of the reasons, health officials said, was to give doctors time to decide how to treat cases of clots, including avoiding giving heparin, a widely used blood thinner.
Following the U.S. suspension, J&J also halted the European rollout of its vaccine.
After concluding its assessment, the EMA has left the decision on using the J&J vaccine to individual EU governments.
"We have already done a very detailed review of the risks and [blood clot] cases with the AstraZeneca vaccine, which gave us the experience to come to a conclusion in the context of the [J&J] vaccine," EMA executive director Emer Cooke said.
After the EMA announcement, J&J said it would resume deliveries in Europe.
In the US, an advisory committee to the federal CDC is scheduled to meet this Friday to recommend the next course of action.
J&J said it remains committed to supplying 100 million doses to the United States.
"We're cautiously hopeful that there is a very viable path forward," J&J CFO Joseph Wolk said during a conference call with analysts.