While the Pfizer and Moderna COVID-19 vaccines have been getting a lot of attention for years, some are actively seeking out the lesser-known Novavax vaccine for their upcoming booster shot this fall. On social media, several people have claimed Novavax has fewer or no side effects — in the words of one X-user, “it doesn’t even hurt your arm.” Meanwhile, Facebook groups like Bay Area Vaccine Hunters are posting “I got Novavax!” and others are sharing where people can get it.
So how does Novavax compare to the Pfizer and Moderna COVID vaccines, and is one really better than the other when it comes to side effects and more? Here’s what experts say.
What are the differences between the Novavax, Pfizer and Moderna COVID vaccines?
Bill Sullivan, a professor of microbiology and immunology at the Indiana University School of Medicine, explains that vaccines generally train the immune system to fight a virus by exposing it to parts of the virus called antigens. “In the case of COVID, the antigen is the spike protein of the virus, the same protein that your immune system responds to during natural infection,” he tells Yahoo Life. “All three COVID vaccines use the same viral spike protein as the antigen, so they’re essentially equivalent in this regard.”
The difference, Sullivan said, is that the Novavax vaccine delivers viral proteins directly into the body. “In contrast, the Pfizer and Moderna vaccines deliver mRNA (messenger RNA) that contains the genetic instructions for cells in the body to make viral proteins,” Sullivan said.
A Novavax spokesperson told Yahoo Life that the company’s COVID-19 vaccine is “the only protein-based vaccine authorized in the United States” and that “this protein-based technology is used to develop many other common vaccines, including influenza and shingles.”
More specifically, the Pfizer and Moderna COVID vaccines target the KP.2, a relatively new variant that circulated this summer, while Novavax targets the JN.1 variant (KP.2’s parent strain) that circulated last winter and spring, Dr. Scott Roberts, an associate professor of medicine specializing in infectious diseases at the Yale School of Medicine, tells Yahoo Life.
As with Pfizer and Moderna, Novavax has not been approved by the FDA but has been granted emergency use authorization (EUA) for its COVID vaccine. “It’s also important to note that the mRNA vaccines are available for people 6 months of age and older,” Sullivan said. “However, the Novavax vaccine is only approved for people 12 years of age and older.”
Why would someone choose Novavax over other vaccines?
Sullivan says some people may prefer the Novavax booster shot because it causes fewer side effects after the shot. “Some people who get the mRNA vaccines experience fatigue, aches and fever the day after, but preliminary reports suggest that these symptoms are less prevalent in people who get the Novavax vaccine,” he says.
But more research is needed to compare side effects between Novavax, Pfizer and Moderna. “We have not conducted head-to-head studies,” a Novavax spokesperson said. “However, our data indicates that the Novavax vaccine provides up-to-date protection against the most commonly circulating variants and that common side effects are manageable.”
Sullivan points out that the low number of people experiencing side effects may have to do with the number of people who have received the Novavax vaccine. “There’s a lot more data on the mRNA vaccines because they’ve been given to billions of people,” he said. “Only about 80,000 people have received the Novavax vaccine so far, so as more people are vaccinated, we may see more reports of mild side effects similar to those we see with the mRNA vaccines.”
There are other reasons to seek Novavax: “Most of my patients tell me they want Novavax because they have some kind of allergy or side effect to the mRNA vaccines,” Roberts says. “Some prefer the ‘traditional’ vaccination method, which is what we do with many other vaccines, including the flu.”
But Roberts added that “while there are no significant differences in vaccine effectiveness, and an overall lack of head-to-head trials, all three vaccines have shown superior efficacy in reducing the risk of severe COVID-19 disease in vaccinated individuals compared with unvaccinated individuals.”
How safe are vaccines using mRNA technology?
Sullivan explains that pre-COVID-19 vaccines have traditionally used proteins as antigens to trigger an immune response, and that’s how Novavax works. “Protein antigens have been used for decades in dozens of vaccines and have a proven track record of being very safe and effective, which is reassuring to a lot of people,” he says.
But COVID-19 has forced scientists to invent ways to produce safe vaccines faster, and “mRNA has proven to be a great solution,” Sullivan says. “They save us the time and effort it takes to make protein antigens because our own body’s own cells can do it for us,” he adds. Sullivan also points out that “numerous studies” have shown that mRNA vaccines are not only effective, but also very safe.
Still, some people are concerned because mRNA vaccines are relatively new, despite decades of research, and the long-term side effects are still unknown, Sullivan said, but he added that “the scientific consensus is that there is no reason why mRNA vaccines would pose a risk years after vaccination.”
Roberts agrees that the mRNA vaccines are very safe, noting that they are currently some of the best-studied vaccines of all time in terms of safety data. “In most cases, the benefits of getting vaccinated outweigh the risk of side effects,” Roberts said. “But people who are concerned should talk to their doctor.”
How effective is Novavax compared to Pfizer and Moderna?
Roberts reiterated that there have been no clear-cut trials comparing all three vaccines head-to-head, and early trials were conducted at different times during the pandemic, making comparisons difficult, but Novavax had a 90% efficacy rate, as did Pfizer and Moderna in early trials, which had efficacy rates of 95% for both, according to the Yale School of Medicine.
“All three are effective in reducing the risk of severe complications from COVID, so I would accept whichever one is offered to me when I get vaccinated,” Roberts said. “The only major difference I’ve found is that Novavax targets a somewhat older variant – it’s the parent of the KP.2 variant that Pfizer/Moderna are targeting. So the efficacy of cross-protection may decrease slightly going forward if variants continue to evolve, but it’s very hard to predict what will be circulating in a few months.”
He added: “I’d be happy with any of the three.”
Sullivan offers this advice: “If you find yourself feeling unwell the day after receiving an mRNA vaccine, it may be worth speaking to your doctor about trying the Novavax vaccine instead next time.”
Both experts say having options when it comes to COVID vaccines is important for a few reasons. Roberts points out that having more than one type of vaccine is crucial because some people may have side effects or allergies to one type of vaccine but not another. “If someone is concerned about one vaccine technology, they have another option,” he says. “It’s nice to have multiple types to choose from.”
Sullivan says all three vaccines will help protect people from getting sick and reduce transmission of the virus, no matter which one you choose. “Whether it’s mRNA-based or protein-based, the vaccines will help achieve those goals,” he says. “If the protein-based vaccines make people feel more comfortable about getting vaccinated, that’s good news for everyone.”