evidence: In addition, the trials follow the FDA's guidance for COVID-19 vaccine development, which reflects the standard clinical trial process: Establish safety and efficacy in adults first, then move to children. Because of the widespread impact of COVID-19, though, many experts say we can’t wait until adult trials are complete. [...] Other COVID-19 vaccine developers, including Johnson & Johnson, Moderna, and AstraZeneca, say they plan to run trials for children in the United States at some point. "Enrollment of children will start once sufficient data are gathered in adults," AstraZeneca stated in reply to an inquiry. Several children’s vaccine trials are underway elsewhere, including the United Kingdom and China; the FDA could approve limited use of those in the United States. [...] If the vaccines prove to be safe and effective, Van Rompay says, "There will be much more confidence and trust [among vaccine developers and regulators] about getting these vaccines into human trials with infants and children."