Biotech company Moderna says it is beginning a phase three trial of its coronavirus vaccine candidate, after successful earlier safety trials.
In this next phase of testing, around 30,000 healthy volunteers will get two doses of the jab, 28 days apart, to see if it can protect against the pandemic virus.
The vaccine is called mRNA-1273 and it contains a small section of genetic code from coronavirus.
It will not cause the disease itself but should hopefully train the body’s immune system to recognise and fight off coronavirus infection.
Half of the volunteers will be given the real vaccine, while the other half, chosen at random, will get two shots of a saline placebo. It will take months to know if the vaccine works.
Moderna’s vaccine is not the first to enter phase three trials - the last phase of testing of a vaccine before it can be submitted to a regulatory authority for evaluation and possible approval.
Phase three testing of a coronavirus vaccine from Oxford University in the UK is already under way. There are more than 120 coronavirus vaccines in various stages of development across the world.