A second coronavirus vaccine is nearing emergency approval in the US after it was endorsed by a panel of experts.
The head of the Food and Drug Administration (FDA) said his agency would move quickly to authorise the Moderna vaccine, allowing the company to begin shipping millions of doses.
It comes days after the US began its largest ever immunisation campaign with the rollout of the Pfizer/BioNTech jab.
The US has recorded more Covid-19 cases and deaths than any other country.
Earlier this week, the death toll passed 300,000.
The advisory panel on Thursday voted 20-0 with one abstention that the benefits of the Moderna vaccine outweigh the risks for those aged 18 and over. The same committee last week backed the Pfizer/BioNTech vaccine, leading to its authorisation for emergency use the following day.
Following the panel’s endorsement, FDA commissioner Stephen Hahn said his agency had informed Moderna that it would work “rapidly” towards issuing emergency use authorisation.
The US has agreed to purchase 200 million doses, and six million could be ready to ship as soon as the vaccine gets FDA approval.
“To go from having a sequence of a virus in January to having two vaccines available in December is a remarkable achievement,” said Dr James Hildreth, a member of the expert panel and CEO of Meharry Medical College in Tennessee.
The Moderna vaccine requires temperatures of around -20C for shipping – similar to a normal freezer.
The Pfizer jab requires temperatures closer to -75C, making transport logistics much more difficult.
Like the Pfizer jab, the Moderna vaccine also requires a second booster shot. Moderna’s second injection comes 28 days after the first.
Centers for Disease Control and Prevention (CDC) guidelines submitted to US states say healthcare workers should be prioritised first, as well Americans living in long-term care homes.
Essential workers are expected to be next in line for the jab, but it will be up to states to decide which industries to prioritise.