April 6 (UPI) -- Oxford University researchers on Tuesday paused a trial of the jointly developed AstraZeneca COVID-19 vaccine in children as Britain's medical regulator reviews rare instances of blood clots in adults.
The trial in children as young as 6 years old was put on hold while Britain's Medicines and Healthcare products Regulatory Agency, or MHRA, reviews rare cases of people experiencing blood clots while simultaneously having low levels of blood platelets, a university representative told CNN.
"Parents and children should continue to attend all scheduled visits and can contact the trial sites if they have any questions," the representative said.
June Raine, chief executive of the MHRA, said the agency was aware of the University of Oxford's decision to pause the trial.
"Participant safety in any clinical trial is our top priority and no safety concerns have been reported with this trial," Raine said.
MHRA found in an analysis from 18.1 million administered doses of the vaccine that seven people died of rare blood clots after being inoculated, although a link between the vaccinations and the clots was not established.
There were 22 reports of brain blood clots, called cerebral venous sinus thrombosis, and eight reports of clotting in those with low platelets.
MHRA advised Britain to continue administering the vaccine in all groups, saying blood clotting is rare enough that the benefits outweigh the risks.
Other nations have restricted the use of the AstraZeneca vaccine. Germany's independent vaccine commission last week recommended those under age 60 who have received the first of the AstraZeneca's two-shot COVID-19 regimen complete their inoculation with a different product.