The Food and Drug Administration says it has decided to continue approving COVID-19 vaccine updates for seniors and others at higher risk of severe disease, but will require vaccine makers to conduct major new clinical trials before approving them for wider use.

In a major policy change, the Food and Drug Administration has announced a plan to limit access to future COVID-19 shots only to people over 65 years old or those with an underlying health condition.

Regulators say updated booster shots won’t be approved for healthy people under age 65 unless drugmakers conduct new trials.