The first coronavirus vaccine tested in the United States raised people’s immune systems just as it begins final testing.
Volunteers who got two doses of the vaccine had high levels of virus-killing antibodies that exceeded the average levels seen in people who had recovered from COVID-19.
No study volunteers experienced a serious side effect, but more than half reported mild or moderate reactions such as fatigue, headache, chills, muscle aches or pain at the injection site. These were more likely to occur after the second dose and in people who got the highest dose.
The vaccine requires two doses, a month apart.
“No matter how you slice this, this is good news,” Dr Anthony Fauci, the US government’s top infectious disease expert said.
The experimental vaccine, developed by Fauci’s colleagues at the National Institutes of Health and Moderna Inc., will start its most important step around July 27: A 30,000-person study to prove if the shots really are strong enough to protect against the coronavirus.
Moderna’s shot, mRNA-1273, uses ribonucleic acid (RNA) – a chemical messenger that contains instructions for making proteins. When injected into people, the vaccine instructs cells to make proteins that mimic the outer surface of the coronavirus, which the body recognises as a foreign invader, and mounts an immune response against.
Experts say a vaccine is needed to put an end to the coronavirus pandemic that has sickened millions and caused over a half million deaths worldwide.
Moderna shares jumped more than 15% in after-hours trading on Tuesday.
The U.S. government is supporting Moderna’s vaccine with nearly half a billion dollars and has chosen it as one of the first to enter large-scale human trials.
Nearly two dozen possible COVID-19 vaccines are in various stages of testing around the world. Candidates from China and Britain’s Oxford University also are entering final testing stages.
Around the world, governments are investing in stockpiles of hundreds of millions of doses of the different candidates, in hopes if any are proven to work.