The FDA is authorizing the release of numerous batches of Moderna's updated COVID-19 booster.
The updated boosters from Pfizer and Moderna were both available earlier in the month as soon as the FDA approved them.
Some pharmacy chains reported trouble keeping Moderna's shots in stock.
Moderna is working closely with the government to deliver more of the updated boosters to pharmacies with low inventory.
Federal health officials continue to urge people to roll up their sleeves for the COVID-19 booster this fall when they get the flu shot.