Pfizer and Moderna, two covid 19 vaccinemakers, are expanding the size of their clinical trials for children ages 5 to 11. A precautionary measure designed to detect rare side effects, including heart inflammation problems that turned up in vaccinated people younger than 30.
President Biden promised at a meeting in Ohio last week that emergency clearance for pediatric vaccines would come soon, but he hasn’t mentioned any specific timeline. It was unsettled whether expanding the studies will affect when vaccines could be approved for children.The Food and Drug Administration has indicated to Pfizer-BioNTech and Moderna that the size and scope of their pediatric studies, as initially considered, were insufficient to detect unusual side effects.Those include myocarditis, an inflammation of the heart muscle, and pericarditis, inflammation of the lining around the heart, multiple people familiar with the trials said.
According to the people familiar with the problem, the F.D.A. asked the companies to include 3,000 children in the 5-to-11-year-old group, the group for whom results were expected first. The Moderna trial began recruiting patients in March to enroll 6,795 participants younger than 12. The participants were to be split equally into three age brackets, including a 6 to 11-year-old group of 2,265 participants each.