A new vaccine that protects against Covid-19 is nearly 95% effective, early data from US company Moderna shows.
The news follows an announcement last week from Germany-based Pfizer and BioNTech that their vaccine was more than 90% effective.
Both companies used a highly innovative and experimental approach to designing their vaccines.
The trial involved 30,000 people in the US with half being given two doses of the vaccine, four weeks apart. The rest had dummy injections.
The analysis was based on the first 95 to develop Covid-19 symptoms.
The data also shows there were 11 cases of severe Covid in the trial, but none happened in people who were immunised.
While the UK has secured 40m doses of Pfizer’s vaccine, and 5m of Moderna’s, it has by far the most riding on the jab being developed by Oxford University and AstraZeneca – of which it has reserved 100m doses.
Although the Oxford vaccine uses a different technology from the Moderna jab, the two vaccines both rely on stimulating cells to produce a specific protein, which in turn triggers an immune response.
Dr Stephen Hoge, the company's president, said he "grinned ear to ear for a minute" when the results came in.
"I don't think any of us really hoped that the vaccine would be 94% effective at preventing Covid-19 disease, that was really a stunning realisation," he told BBC News.
Moderna says it will apply to regulators in the US in the coming weeks. It expects to have 20 million doses available in the country.
The company hopes to have up to one billion doses available for use around the world next year and is planning to seek approval in other countries too.
No significant safety concerns have been reported.Short lived fatigue, headache and pain were reported after the injection in some patients.
Moderna's vaccine appears to be easier to store as it remains stable at minus 20C for up to six months and can be kept in a standard fridge for up to a month.
Meanwhile, Oxford/AstraZeneca team expect to have findings from their phase 3 clinical trial within a matter of weeks.
Should that be the case, and the team also release their full safety data, some have suggested the vaccine could gain regulatory approval about the same time or before the Pfizer/BioNTech vaccine.
Moderna was founded in 2010 by a stem cell biologist, Derrick Rossi, and two financial backers, with the idea that mRNA – the molecule that sends genetic instructions from DNA to a cell’s protein-making machinery – could be re-engineered to develop drugs and vaccines.
The team behind the Moderna vaccine is led by Tal Zaks, Moderna’s chief medical officer and a former head of global oncology at Sanofi.