An advisory panel for the Food and Drug Administration voted 20-0 to give the drugmaker approval for its vaccine on Thursday.
It becomes the second company to get the go ahead, joining Pfizer, whose vaccine is now being given to patients across the US.
The FDA is expected to quickly take up the recommendation of the panel that the benefits of the vaccine, which was produced by the drug company and the National Institutes of Health, outweigh the risks for people over the age of 18.
The drug will now join the largest ever vaccination scheme in US history, and go first to health care workers and nursing home residents.
US officials plan to ship 6 million doses of the Moderna vaccine in a first wave and, unlike Pfizer’s shot, which must be kept at ultra-cold temperatures, it can be stored in a regular freezer.
The government has ordered 200 million doses of Moderna’s vaccine to go with 100 million from Pfizer.
Moderna’s vaccine is given in two shots that are taken 28 days apart, and has been proven to be 94 per cent effective.
Both vaccines use small pieces of genetic code called messenger RNA to get the body’s immune system to produce coronavirus antibodies, without actually using any virus.
They are the first vaccines of their kind ever authorised for use.
The Moderna vaccine, like the Pfizer one, has shown no serious reactions but has caused pain at the injection site, fatigue, headache, muscle pain, joint pain and chills.
