GAITHERSBURG, Md. — Maryland-based vaccine maker Novavax announced June 14 it plans to ask for FDA emergency approval for its COVID-19 vaccine after preliminary data boasted a 90% efficacy rate. Citing raw-material shortages that have slowed production, the company will wait until the end of September for authorization.
The Verify team talked to two Johns Hopkins University vaccine experts, Dr. William Moss, the Executive Director of the International Vaccine Access Center, and Dr. Namandje Bumpus, the Director of the Department of Pharmacology and Molecular Sciences, to break down everything you need to know about the Novavax vaccine.
What you need to know:
- This two-dose vaccine is made up of the spike protein found on the virus that causes COVID-19, SARS-CoV-2. The other vaccines provide the instructions to make the spike protein; Novavax skips that step.
- Exposing your immune system to the spike protein means you’ll know how to fight off the virus itself if you come in contact with it
- Trials found an overall efficacy rate of 90.4%, but it varies depending on the variant
- The vaccine can be stored at normal refrigeration temperatures
How effective is the Novavax vaccine?
Novavax says the overall efficacy of its vaccine candidate is 90.4%. Efficacy is the measurement of how well a vaccine is at preventing disease. The company's trial measured specific effectiveness against a number of SARS-CoV-2 variants; of the variants considered of "concern" or of "interest," as defined by the CDC, efficacy was 93.2%.
There was a small trial in South Africa which found 50% efficacy against what's known as the Beta variant. Dr. Moss says Novavax is evaluating a newer version of their vaccine to fight off Beta, which the CDC says is about 50% more transmissible. Novavax hasn't reported any data yet on how its vaccine candidate bodes against the Delta variant, first identified in India.
All cases of COVID-19 in trial vaccine recipients were mild, according to Novavax, and there were ten moderate and four severe COVID-19 cases in the placebo group. Novavax says this means its vaccine touts 100% efficacy against moderate and severe disease.
"The more vaccines, the better, and particularly vaccines that have this high level of efficacy," Dr. Moss says. "90%, that's really fantastic. That puts it in that top group of vaccines in terms of the protective efficacy. And so I see it having a big role globally."
How does the Novavax COVID-19 vaccine work?
Novavax's two-dose vaccine candidate is what's called a protein vaccine. It has the same end point as the Pfizer, Moderna and Johnson & Johnson vaccines: expose your immune system to SARS-CoV-2's signature spike protein and train your body to fight it off. But, Novavax takes a different path to get there.
The Novavax approach is an injection of the spike protein itself, which is different from the Pfizer, Moderna and Johnson & Johnson vaccines which inject instructions so our cells can make the spike protein. Our experts stress that the protein on its own will not infect you with COVID-19.
A dose of just the protein is less work for our cells, as the bulk of that work takes place in the labs. To get the large number of spike proteins needed to produce vaccine doses, scientists create mass amounts of spike proteins using cells extracted from moths (yes, the insect).
"It's not like they have these cages of moths," Dr. Moss explains. "It's not moths, per se, that are being used, but moth cells...the moth cells are acting like little factories to create proteins."
Dr. Moss and Dr. Bumpus told us using cells in a culture to build proteins is a traditional strategy in labs. On the small scale, it would take place in petri dishes or test tubes. Novavax scientists are placing the spike protein into a virus that only infects insect cells, then infecting mass amounts of moth cells, and harvesting the spike proteins they replicate.
"I would think of it kind of like an assembly line, it's a way to make proteins," Dr. Bumpus says. "That's the type of thing we've been doing in labs for a long time to make other types of proteins....it's very common."
Once the protein is injected, our immune system gets to work, so if the real virus enters our system, infection and disease are less likely. The tested vaccine regimen is two doses 21 days apart.
While these new vaccine innovations are exciting, our experts tell us this isn't brand new technology. Dr. Moss told us other well-known protein vaccines are those used to prevent Tetanus, Polio, Hepatitis B and Human Papilloma Virus (HPV).
How is it stored?
According to a Novavax press release, their vaccine candidate can be stored at normal refrigeration temperatures, 35.6-46.4 degrees Fahrenheit (2-8 degrees Celsius) — the same as Johnson & Johnson and AstraZeneca's vaccines.
These refrigeration temperature vaccines are much easier to store than the Pfizer and Moderna vaccines, which require ultra-cold freezer storage to stay usable. Novavax is the latest vaccine to provide a vaccine option to countries and communities without access to the extremely expensive technology needed to transport and store the mRNA options.