WASHINGTON (AP) — Dealing the White House a stinging setback, a government advisory panel overwhelmingly rejected a plan Friday to give Pfizer COVID-19 booster shots across the board, and instead endorsed the extra vaccine dose only for those who are 65 or older or run a high risk of severe disease.

The twin votes represented a heavy blow to the Biden administration's sweeping effort, announced a month ago, to shore up nearly all Americans' protection amid the spread of the highly contagious delta variant.

The nonbinding recommendation — from an influential committee of outside experts who adv...