Researchers at Oxford University have paused a small pediatric clinical trial of the coronavirus vaccine it is developing with AstraZeneca.
In a statement, the university said it is awaiting the results of a safety review from UK regulators, the Medicines and Healthcare products Regulatory Agency (MHRA).
An Oxford spokesperson said there are no safety concerns concerning the pediatric research, but the trial is paused while they await “additional information” from MHRA, which is reviewing possible links between the vaccine and rare blood clots in adults.
The trial is testing the effectiveness of the vaccine in up to 300 children between the ages of 6 and 17.
“Whilst there are no safety concerns in the paediatric clinical trial, we await additional information from the MHRA on its review of rare cases of thrombosis/thrombocytopaenia that have been reported in adults, before giving any further vaccinations in the trial,” the university said.
AstraZeneca did not comment.
The trial pause is the latest development in the ongoing saga over the AstraZeneca vaccine, which has not had a smooth rollout overseas.
Concerns over the blood clotting events in a small number of recipients have dogged the shot in recent weeks, and resulted in more than a dozen European countries temporarily suspending use of the vaccine last month, while waiting on the European regulatory agency’s recommendations on how to proceed.
The European Medicines Agency (EMA) endorsed the safety of the shot, but said it could not rule out a link to the blood clots, and would add a warning to the product in order to draw attention to the possibility of such rare side effects.
Many European countries are relying heavily on the Oxford-AstraZeneca vaccine, as it is being sold using a nonprofit model and is far cheaper to make than other COVID-19 vaccines.
The vaccine is authorized for adults age 18 and older overseas, but the company has not yet filed for emergency authorization in the U.S.