The more vaccines we have available to fight COVID-19, the more lives we can save, and the sooner we can all get our lives closer to normal. Currently there are two vaccines approved by the U.S. Food and Drug Administration for emergency use, and many more are being tested in clinical trials.
One of the promising vaccines in trial, NVX-CoV2373, created by U.S. biotechnology company Novavax Inc., recently started phase III trials across the United States, including at UNC Health. In phase III trials, researchers expand the number of participants involved in order to get a better idea of how effective the vaccine is while continuing to monitor for any side effects. Before moving to a large phase III trial, a product has to be shown as safe to use in people in smaller groups of participants.
Cynthia Gay is the site leader for the Carolina Novavax trial and an infectious diseases expert. She also leads the Moderna clinical trial at Carolina.
Gay spoke to UNC Health Talk to explain how the clinical trial works, what is different about the Novavax vaccine and why it will help vaccinate even more people if approved by the FDA.
Why we need more vaccines
“We need to think of this as a team effort. If we want businesses to reopen, kids to go back to school, for us all to get back to a more normal life, we need to get the whole team vaccinated,” Gay says. “The only way all the players on the team can get vaccinated is if we have enough doses.”
Each vaccine that gets emergency use authorization from the FDA means millions more doses of vaccine become available to the public. In addition to more doses, each vaccine is slightly different in what it requires to transport or store it. For example, the vaccine produced by Pfizer/BioNTech that has been approved for emergency use needs to be kept at very cold and specific temperatures, which can make transporting and handling it difficult. The Novavax vaccine requires average refrigeration. This difference makes vaccines like Novavax much more accessible to rural communities in the United States and areas across the world that might have fewer resources to handle transportation and storage at very specific temperatures.
“This vaccine would be a game changer for resource-poor settings, to have a vaccine that can be administered on a widescale basis in rural areas and places with less infrastructure,” Gay says.
And because of the easier-to-maintain temperature requirements for transportation and storage, fewer vaccines will be lost to mistakes or breakdowns in technology.
How the Novavax vaccine works
“Every vaccine is trying to achieve the same goal,” Gay says. “It wants to trick your immune system into thinking that it’s seen a certain virus before and have it develop an immune response specific to that virus. Having that immune response ready when someone encounters the virus means you’ll have less of a chance of getting sick or you’ll have less severe illness.”
The COVID-19 vaccines being developed focus on the spike protein of the SARS-CoV-2 virus, which allows the virus to enter into healthy cells and cause COVID-19. To develop immunity, your body is introduced to this protein and in response, your immune system creates antibodies to the protein.
The Pfizer/BioNTech and Moderna vaccines already available for emergency use deliver messenger RNA that prompts the body to create the SARS-CoV-2 spike protein, leading to the production of antibodies.
In contrast, the Novavax vaccine uses a spike protein developed by scientists in a lab. Once injected, the body’s immune system recognizes the protein as something foreign and begins creating antibodies to fight off what it perceives as a threat to your health. Since only a piece of the virus is being used, you cannot get COVID-19 from the vaccine. You’ve probably already had a vaccine like this before — think flu, chickenpox, MMR (measles, mumps, rubella) and polio.
“Protein-based vaccines, like the Novavax vaccine, are given to millions of people on a regular basis,” Gay says. “It’s a proven approach to eliciting antibodies and an immune response. This is not a new vaccine technology.”
At the same time, Gay says that because the Pfizer/BioNTech and Moderna vaccines also target the SARS-CoV-2 spike protein, it bodes well for the effectiveness of the Novavax vaccine, even if it uses a different delivery system.
How the trial works
For its North American phase III trial, Novavax is aiming to recruit 30,000 participants across 100 sites in the United States and Mexico. Participants will randomly receive either the vaccine or placebo in two doses, 21 days apart. Two-thirds of volunteers will receive the vaccine and one-third will receive the placebo in order to test how well the vaccine works. Participants will be followed for 24 months after they are vaccinated to monitor their health and safety. The trial will require about eight in-person visits to a clinic over the two-year period, and participants will be asked to make regular entries in an electronic diary to help monitor symptoms that may arise from the vaccine or COVID-19.
This clinical trial aims to proportionally include diverse populations who are most vulnerable to COVID-19. That includes people of color and those living with comorbidities such as kidney disease, lung disease, heart disease, obesity, diabetes, liver disease and HIV. Carolina aims to recruit 300 participants across its trial locations, which include the UNC Medical Center in Chapel Hill and two sites in Chatham County.
Preliminary results from the trial will be released once enough data is collected from participants after they receive both doses, similar to other COVID-19 vaccine trials.
Why you should consider joining the trial
Participating in a COVID-19 vaccine clinical trial means being part of history. In the case of Novavax, playing a role in the process means you may help people in rural and disadvantaged communities have access to a vaccine.
A perk of participating is that if you fall into a later phase of your state’s vaccination plan, then a clinical trial may help you receive a vaccine earlier.
To see if you are eligible to participate in Carolina’s Novavax vaccine clinical trial, or other upcoming trials near you, visit the COVID-19 Prevention Network Volunteer Screening Registry.
Cynthia Gay is an associate professor of medicine in the division of infectious diseases in the UNC School of Medicine. She is a practicing physician and the medical director of the UNC HIV Cure Center.