The US is close to approving a second COVID-19 jab for use, as the country ramps up its vaccination programme.
America’s regulatory authority, the Food and Drug Administration (FDA), said its early analysis of the Moderna vaccine confirmed its 95% efficacy.
And on Tuesday, FDA staff endorsed it as safe and effective.
A panel of independent experts will gather on Thursday to discuss the vaccine, with emergency use authorisation by the FDA set to follow shortly afterwards, possibly on Friday.
The FDA normally follows the advice of the panel, but is not required to do so.
Similar to the Pfizer vaccine, the Moderna inoculation requires two doses several weeks apart.
Although Moderna reported no major safety issues from its trial, the FDA will scrutinise the data to ensure the jab is safe.
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The vaccine’s main side-effects appear to be fatigue and aching muscles after the second jab – although these effects are common with most injections and is indicative that the vaccine is working to create antibodies.
It comes as hospitals across the US ramped up their vaccination programme using the Pfizer/BioNTech jab, which was cleared by the FDA last week.
The Pfizer vaccine, which has to be transported in dry ice to keep it at -70C, is due to arrive at another 400 hospitals and distribution sites on Tuesday – a day after it was revealed more 300,000 people have died in the US with COVID-19.
Frontline health workers and elderly patients will get the first three million doses of the Pfizer jab, with hundreds of millions more arriving over the next few months.
Florida and New Jersey are among the states taking deliveries of the Pfizer vaccine, with 176,000 doses alone hitting those states.
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Private delivery companies, such as FedEx, have been drafted in by the US government to help get the vaccine across the country from its factory in Michigan, with more shipments due in the coming days.
Army General Gustave Perna, chief operating officer for Operation Warp Speed, said: “We’re starting our drumbeat of continuous execution of vaccine as it is available.
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“We package and we deliver. It is a constant flow of available vaccine.”
Officials expect that 20 million Americans will be able to get their first doses by the end of the year, with a further 30 million in January.