Novavax's coronavirus vaccine, called NVX-CoV2373, differs from the three vaccines already being distributed in the United States. The vaccine relies on what is called recombinant nanoparticle technology and Novavax's adjuvant, called Matrix-M, to stimulate an immune response and stimulate high levels of neutralizing antibodies.
When the genetic sequence for the coronavirus was published, Novavax scientists identified the gene for the spike protein and created a modified version of that gene. The researchers cloned the genes into a baculovirus that infects insects. They then infected moth cells -- specifically, cells from the fall armyworm insect -- with that virus, prompting them to produce the coronavirus spike protein.
These virus-like nanoparticles were harvested to make Novavax's vaccine.
"The whole idea of the vaccine is to show the immune system something that looks, tastes and acts like a virus, with the exception that it doesn't make you sick. So we made the spike protein. We put it in a particle -- basically, like a soap bubble -- and it's the size of the virus," Glenn said.
"It's not infectious. We never touch the coronavirus itself," he added. "Then that is given to people, and they make an immune response that's very much focused just on the spike -- and I would say, the hallmark of our vaccine is it gives a very strong immune response with very few side effects, and the dose is very small and the vaccine can be stored with normal refrigerated temperatures."
That's different from the Covid-19 vaccines made using messenger RNA carried in fatty particles called lipids. They're more fragile and must be kept frozen.