The European drug regulator said on Friday that it had begun to review reports of bleeding in people vaccinated with AZN.US 's COVID-19 vaccine and was investigating blood clots after the injection of Johnson's vaccine, Zhitong Financial APP learned.

The European Drug Administration said that after receiving the COVID-19 vaccine from Johnson's Janssen Company, it had reported four serious and rare cases of low blood platelet thrombosis, one of which was fatal. In addition, five cases of capillary leakage syndrome associated with AstraZeneca vaccine were reported.

As of Friday's close, AstraZeneca closed up 0.89% at $49.94, while Johnson closed down 1.06% at $161.25.