Moderna's Covid-19 vaccine is safe and 94% effective, US regulators say, clearing the way for US emergency authorisation.
The analysis by the US Food and Drug Administration's (FDA) means it could become the second coronavirus vaccine to be allowed in the US, reports the BBC.
It comes one day after Americans across the country began receiving jabs of the Pfizer-BioNTech vaccine.
The news comes as the US coronavirus death toll passes 300,000, according to Johns Hopkins University.
Endorsement of the Moderna vaccine by FDA scientists was announced on Tuesday, two days before the vaccine panel meets to discuss emergency approval.