The Food and Drug Administration plans to authorize updated versions of Pfizer-BioNTech’s and Moderna’s Covid boosters around Labor Day, said two people familiar with the discussions. The Biden administration is preparing to distribute the updated booster shots to teenagers and adults as part of its fall booster campaign. Both Pfizer's and Moderna's so-called bivalent vaccines target the BA.4 and BA.5 omicron subvariants, in addition to the original coronavirus strain in a single shot. BA.5 is responsible for nearly 90% of all new Covid cases in the U.S., according to data from the Centers for Disease Control and Prevention.