WASHINGTON (AP) — The Biden administration said Friday it has reached an agreement with Moderna to buy 66 million doses of the company's next generation of COVID-19 vaccine that targets the highly transmissible omicron variant, enough supply this winter for all who want the upgraded booster. The order of the bivalent shot follows the announcement last month that the federal government had secured 105 million doses of a similar vaccine from rival drugmaker Pfizer. Both orders are scheduled for delivery in the fall and winter, assuming regulators sign off on their effectiveness.