TEHRAN (Tasnim) – Three potential COVID-19 vaccines are making fast progress in early-stage testing in volunteers in China and the US, but it is still a long road to prove if they’ll really work.
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 AP 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.
Last week, CanSino filed a report showing it aimed to enroll 500 people in this next study, comparing two doses of the vaccine to dummy shots. As of Monday, 273 of the volunteers had been injected, state media said.