Moderna Inc. /zigman2/quotes/205619834/composite MRNA +0.98% said Thursday that the U.K. purchased an additional 60 million doses of its COVID-19 vaccine, to be delivered in 2022 and 2023. As part of the agreement, the doses can include boosters, and the U.K. can increase or decrease the number of doses it's buying by 20%. Moderna's stock is up 197.3% so far this year, while the broader S&P 500 /zigman2/quotes/210599714/realtime SPX +0.56% has gained 21.6%.


