British drug regulators have become the first in the world to authorize an updated version of Moderna’s COVID-19 vaccine that includes protection against the Omicron variant of SARS-CoV-2, which the government said would be offered to people aged 50 and older starting in the fall. In a statement on Monday, the British Medicines and Healthcare Regulatory Agency said it had approved Moderna’s combination “bivalent” vaccine, which would be used as an adult booster shot. Each dose of the booster shot would target both the original COVID-19 virus that was first detected in 2020 and the Om...