A UK trial testing the COVID-19 vaccine developed by AstraZeneca and the University of Oxford on children and teenagers has been paused pending additional data from a probe by the UK’s medicines regulator on possible links with rare blood clotting issues in adults. University of Oxford’s Prof. Andrew Pollard said that there were “no safety concerns” in the trial of 300 volunteers aged 6-17 years, but that it will wait for further data to be released from the Medicines and Healthcare Products Regulatory Agency (MHRA)—the UK drugs watchdog—before giving any further vaccinations. The trial began in February to assess whether the shot produces a strong immune response in those in the age group. The pause came shortly after Marco Cavaleri, a senior official for the European Medicines Agency (EMA) suggested that there is a link between AstraZeneca’s COVID-19 vaccine and very rare blood clots in the brain, known as cerebral venous …