Moving forward, the FDA will adopt the following Covid-19 vaccination regulatory framework: On the basis of immunogenicity — proof that a vaccine can generate antibody titers in people — the FDA anticipates that it will be able to make favorable benefit–risk findings for adults over the age of 65 years and for all persons above the age of 6 months with one or more risk factors that put them at high risk for severe Covid-19 outcomes, as described by the CDC (Figure 2). For all healthy persons — those with no risk factors for severe Covid-19 — between the ages of 6 months and 64 years, the FDA anticipates the need for randomized, controlled trial data evaluating clinical outcomes before Biologics License Applications can be granted. Insofar as possible, when approving a Covid-19 vaccine for high-risk groups, the FDA will encourage manufacturers to conduct randomized, controlled trials in the population of healthy adults as part of their postmarketing commitment.

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