A trial of the Oxford-AstraZeneca Covid vaccine on children has stopped giving out jabs while the UK’s medicines regulator investigates a possible link with rare blood clots in adults.
The trial of the Oxford-AstraZeneca vaccine on children, which started in February, is assessing whether the jab produces a strong immune response in those aged between six and 17.
Its suspension comes after a European Medicines Agency (EMA) official, speaking in a personal capacity, said there appeared to be a link with the jab and rare blood clots.
Prof Andrew Pollard from the University of Oxford said: “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.”
Around 300 volunteers signed up.
Participants are advised to continue to attend all scheduled visits and can contact the trial sites if they have any questions.
Updates from the EMA and the UK’s regulator, the Medicines and Healthcare Products Regulatory Agency (MHRA), are expected in the coming days.
The EMA said its safety committee had “not yet reached a conclusion and the review is currently ongoing”.
The MHRA says the benefits of the jab continue to outweigh any risk.
The MHRA is investigating reports of a very rare and specific type of blood clot in the brain, known as cerebral venous sinus thrombosis (CVST), occurring together with low levels of platelets (thrombocytopenia) following vaccination.
A number of countries have suspended the use of the Oxford-AstraZeneca jab among younger people, including in Germany, which has paused it for people aged below 60, and Canada, where the jab is not being given to those under 55.
The MHRA has said it identified 30 cases of rare blood clot events out of 18.1 million doses of the jab administered up to and including 24 March in the UK. There have been seven deaths among the 30 cases.