The University of Oxford has interrupted the administration of doses of the COVID-19 vaccine it co-developed with AstraZeneca PLC AZN,
AZN,
in a small UK study aimed at evaluating safety and effectiveness in children and teens, to wait for more information on rare blood clotting problems found in a small group of adults who got it, the Wall Street Journal reported Tuesday. The trial started in mid-February and involved more than 200 young people aged 6 to 17, the newspaper said. It quoted an Oxford spokesperson as saying that the trial had found no safety concerns, but that broader concerns and a review of the vaccine by regulators in the UK and the European Union were behind the movement. The European Medicines Agency previously said it expects to update the public on its investigation into the blood clotting problem later this week.