The Food and Drug Administration (FDA) has asked Pfizer and Moderna to expand their COVID-19 vaccine trials for 5 to 11-year-olds in an effort to determine whether a rare side effect in the form of heart inflammation is more common among younger groups, according to reports. The FDA has asked the two pharmaceutical companies to expand their 5-to-11-year-old trial groups to include at least 3,000 children, according to the New York Times. A spokesman for Moderna confirmed to The Washington Post that the company is “actively discussing a proposal” with the FDA to expand its trial “to enroll a larger safety database which increases the likelihood of detecting rarer events.” The spokesperson added that a final number for the size of the trial has yet to be determined. The New York Times report said Pfizer is also in talks to expand its vaccine trials in younger children, with a spokesperson for …