Moderna Inc said on Thursday it had dosed the first participant in a mid-to-late stage study testing its COVID-19 vaccine candidate in adolescents aged 12 to less than 18. … “Our goal is to generate data in the spring of 2021 that will support the use of mRNA-1273 in adolescents in advance of the 2021 school year,” said Chief Executive Officer Stéphane Bancel.