Agency will ask drugmakers for large trials for new versions of vaccines meant for healthy adults and children.

The FDA announced a policy shift for COVID-19 vaccine approvals to focus on Americans considered high-risk of contracting the virus, and those older than age 65.

In a major policy shift, federal health officials anticipate the shots will be made available to adults 65 and older as well as children and younger adults who have one or more risk factors that make them more vulnerable to severe COVID-19.