Today marks the beginning of the biggest U.S. vaccine trial yet for coronavirus. Moderna has enrolled 30,000 people in the phase 3 trial. It will take place at 89 sites across the country. The New York Times writes, “Half will receive two shots of the vaccine, 28 days apart, and half will receive two shots of a saltwater placebo.”
Researchers will then monitor the subjects, looking for side effects and waiting to see if significantly fewer vaccinated people get Covid-19, indicating that the vaccine works. The main goal is to determine whether the vaccine can prevent the illness. The study will also try to find out if it can prevent severe Covid-19 and death; if it can prevent infection entirely, based on lab tests; and if just one shot can prevent the illness.
The CEO of Moderna, Stephane Bancel, told CNBC (watch above) he hopes to know by November, how effective the vaccine is. Elissa Greene, one of the vaccine participants taking part. She walked CNN through how the trial will work.
“I’m okay with not knowing,” a nurse practitioner says about the uncertainty that comes with participating in Phase 3 of the coronavirus vaccine trial. “In reality, there’s a lot of things we don’t know… I’m older and I’ve just gotten used to going with the flow.” pic.twitter.com/VvMJJRlTPW
— CNN This Morning with Kasie Hunt (@CNNThisMorning) July 27, 2020
Organizers of the trial say there will have to onlybe approximately 150 cases of COVID-19 among study participants to say with confidence that the vaccine is actually preventing disease. How long it takes to reach that number, and how many participants will have to be enrolled in the study, is an open question. It depends in part on how much virus is circulating in the communities where the trial takes place.
The National Institute of Allergy and Infectious Diseases (NIAID) writes that “mRNA-1273 has shown promise in early-stage clinical testing led by #NIAID. The vaccine is generally well tolerated and prompted an immune response in healthy adults.”