Coronavirus vaccine showing promise in first phase

The first coronavirus vaccine tested in humans is showing early signs of promise and now scientists and researchers at the National Institutes of Health and Moderna Inc. are getting ready for the most critical step: a 30,000 person study.

"This is a new phase in vaccine development, the first two phases were looking at safety and immune response. What’s different about phase 3 is for the first time we can see if this will actually protect someone from infection," said Dr. Matt Laurens, an infectious disease specialist and lead investigator on the upcoming Phase 3 trial for the Moderna Vaccine at the University of Maryland School of Medicine.

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UMD School of Medicine is just one of dozens of sites across the country that will be taking part in Phase 3 trials. 

According to results published in the New England Journal of Medicine, the 45 volunteers who participated in Phase 1 of Moderna trials developed what is called "neutralizing antibodies" in their bloodstream that will block the coronavirus infection – and the findings show that the antibodies are comparable to those found in people who survived COVID-19.  

"It showed a strong immune response, it showed a vaccine with an acceptable safety profile,  low side effect profile, so this gives us real hope," said Dr. Laurens. 

In a Phase 3 trial, everything is randomized. Half of the 30,000 healthy participants will receive the MRNA vaccine, the other half a placebo. Scientists will look to see if the vaccinated group has fewer infections.

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But when it comes to safety, is 30,000 participants enough? 

"30,000 is a start for will be important to carefully document safety in the 30,000. We do things differently in this Phase 3 trial ...we ask them to record their symptoms daily, they have thermometers to take home...we ask them to tell us if they feel fatigued if they have muscle pain, so all this is done more rigorously in a Phase 3 trial," said Dr. Laurens. 

Dr. Laurens says the focus of Moderna’s Phase 3 will be to target the most vulnerable communities, with participants from the Latino and African American communities to older adults with underlying health issues. 

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As far as when the vaccine could be readily available? Dr. Laurens points to mid-next year. He says it depends on how the hotspots in the U.S. change as far as the sites that test the vaccine. 

"Because to test the vaccine we have to be able to have positive cases and determine if the vaccine is preventing disease in participants," he said. 

According to a new study out of the U.K., natural immunity, the level of antibodies could drop in a matter of months. 

Dr. Laurens said: "Yes, we do not know enough about the immune response needed to prevent infection over the long-term, and this needs to be researched. Certainly, we have to consider the potential need for booster vaccination down the road, should the immune response to vaccination diminish over time. This is true for the Moderna vaccine and any other COVID-19 vaccine in development."