(AP) — Three potential COVID-19 vaccines are making fast progress in early-stage testing in volunteers in China and the United States, but it’s still a long road to prove if they’ll really work.
China’s CanSino Biologics is beginning the second phase of testing its vaccine candidate, China’s Ministry of Science and Technology said Tuesday.
In the US, a shot made by the National Institutes of Health and Moderna Inc. isn’t far behind. The first person to receive that experimental vaccine last month returned to a Seattle clinic Tuesday for a second dose.
NIH infectious disease chief Dr Anthony Fauci told The Associated Press there are “no red flags” so far and he hoped the next, larger phase of testing could begin around June.
A third candidate, from Inovio Pharmaceuticals, began giving experimental shots for first-step safety testing last week in the US and hopes to expand its studies to China.
Initial tests focus on safety, and researchers in both countries are trying out different doses of different types of shots.
But moving into the second phase is a critical step that allows vaccines to be tested in many more people to look for signs that they protect against infection.