Novavax introduces protein-based COVID-19 vaccine option to unvaccinated Americans
Public health officials and a Stanford microbiology and immunology professor are cautiously optimistic that the first protein-based COVID-19 vaccine option will reach people who previously feared getting vaccinated.
The Novavax COVID-19 vaccine has been approved by the Center for Disease Control and Prevention (CDC) on July 19, after the Food and Drug Administration authorized for emergency use earlier in July. The two-dose primary series vaccine has been available since early August.
Produced by the American biotechnology company Novavax, the vaccine is the fourth COVID-19 vaccine authorized for use in the United States and the first to use traditional protein-based technology. mRNA vaccines, like those from Pfizer-BionNTech and Moderna, instruct cells to make a function-less recognizable COVID-19 protein on its own; the immune system then mounts a response to the foreign protein. The Novavax vaccine, on the other hand, uses a more common and older technology that directly introduces the recognizable protein to boost immunity.
With some having Express Concerns about receiving an mRNA vaccine during the initial vaccine distribution, the Novavax vaccine offers an alternative to mRNA vaccines from Pfizer-BioNTech and Moderna and the Johnson & Johnson/Janssen virus vector vaccine.
“In the United States, we have saturated the market for people who want to get vaccinated,” said professor of microbiology and immunology Holden Maecker. “The problem was more reaching people who don’t want to get vaccinated.”
Rajeswari Ponnuswamy, who is a family physician at the Palo Alto Medical Foundation, said some of her patients have refused COVID-19 vaccines due to concerns about new technologies.
“Now that we have a vaccine that uses a technology that has been tested for many years, it will be easier to convince patients to get vaccinated because we can give them examples of times they have received a vaccine using a similar technology, such as the one for hepatitis B,” Ponnuswamy said.
Novavax is 90.4% efficient to prevent infection and 100% effective in preventing severe symptoms, an efficacy comparable to the Pfizer-BioNTech and Moderna vaccines. It also has similar side effects. According to Maecker, experts predict it will likely also be limited in preventing infection with the Omicron variant.
“The Novavax trials were done long before Omicron became widespread in the United States, and therefore [while] our effectiveness estimates are quite high for Novavax,” the CDC said. Advisory Committee on Immunization Practices President Grace Lee. “But these estimates of effectiveness are in a different time frame.”
What really sets the Novavax COVID-19 vaccine apart is its manufacturing process. According to Novavax website, the spike protein gene of the COVID-19 virus is donated to an insect virus, which is then used to infect ringworm cells. As the virus replicates in the cell, the protein gene is transcribed into mRNA in the nucleus, causing the cell to make large amounts of protein. After harvesting and purifying the proteins, they are arranged around a core of nanoparticles, which will allow the immune system to recognize the protein from different angles in the event of an infection.
The second component of the vaccine is Novavax patented Matrix-M adjuvant. An adjuvant is a substance used to increase the immune response to a vaccine, which can help the immune system recognize an antigen and provide longer protection. Novavax sources itself from saponins, a detergent-like compound found in the bark of the soap tree in Chile. When the trees are pruned, the bark is crushed and made into two parts, which are then freeze-dried into powders containing crude saponins. Both powders are mixed with fats to create Matrix-A and Matrix-C particles. When combined, the Matrix-M adjuvant is formed.
“There’s a somewhat novel combination of things in this vaccine,” Maecker said. “But in terms of the vaccine class, it’s a traditional protein-based formulation.”
According the CDC, between 26 and 37 million adults in the United States are unvaccinated. According to Lee, despite the old technology behind the Novavax vaccine, it is unlikely to influence anti-vaccine anxiety.
A 2022 survey found that “16% of those who are unvaccinated would probably or definitely receive a protein-based vaccine, so 84%, despite the availability of a different vaccine platform, are still hesitant to receive a vaccine COVID-19,” Lee said.