Moderna suggests giving younger US citizens half doses of its vaccine could be a better strategy to get to Herd Immunity faster

https://www.reuters.com/article/uk-health-coronavirus-usa-moderna-idUKKBN2980O0

sample quote

“ We know that for the Moderna vaccine, giving half of the dose to people between the ages of 18 and 55, two doses, half the dose, which means exactly achieving the objective of immunizing double the number of people with the doses we have,” Slaoui said.

“We know it induces identical immune response” to the full dose, he added.

end quote

makes sense to me