GENEVA — It’s nearly launch time for COVAX, the United Nations’ unprecedented program to deploy COVID-19 vaccines for hundreds of millions in need around the globe.

More than two months after countries like Britain and the United States started immunizing their most vulnerable people, the U.N.’s health agency gave its approval to a vaccine developed by Oxford University and AstraZeneca, which should trigger the release of hundreds of millions of doses by COVAX.

COVAX missed its own target of starting vaccination in poor countries at the same time as immunizations were rolled out in rich countries, and numerous developing countries have signed their own deals to buy vaccine, fearing the program won’t deliver.

The World Health Organization and partners hope COVAX can finally start shipping out vaccines later this month.