Does the Novavax COVID-19 vaccine cause fewer side effects?

Erin Kissane, co-founder of the COVID-19 Tracking Project, rolled up her sleeve to receive the Novavax vaccine in mid-October, shortly after it was finally approved in the U.S. Like other people with autoimmune diseases, she wants to protect herself from a potentially devastating infection.

Kissane’s autoimmune arthritis appears to make her susceptible to the vaccine’s unusual side effects. After receiving an mRNA vaccine booster last year, her joints hurt so much that the doctor prescribed steroids for the inflammation.

He still believes the mRNA vaccines are “miraculous,” knowing that COVID-19 could be much worse than the temporary pains. But when the pain subsided, he pored over studies on the Novavax shot, a vaccine based on proteins instead of mRNA and which has been used since early 2022 in other countries.

In the United Kingdom they found that people more frequently reported temporary reactions, such as low fever, fatigue and pain, as their immune system strengthened in the days after the booster vaccination with the Moderna mRNA vaccine compared to that of Pfizer. Those who received the Novavax one had fewer complaints than either.

That finding was corroborated in an analysis of international data published last year.

A vial of the coronavirus vaccine produced by Novavax is displayed at George University Hospital in London, August 5, 2021.
A vial of the coronavirus vaccine produced by Novavax is displayed at George University Hospital in London, August 5, 2021.
Associated Press

Such studies have led people with long COVID-19 and chronic fatigue syndrome (also known as myalgic encephalomyelitis or ME/CFS) to use Novavax as well, since the Food and Drug Administration (FDA) and the Centers The CDC gave the green light to the vaccine — updated to protect against recent variants like Omicron — nearly three weeks after recommending updated mRNA vaccines in September.

The wait paid off for Kissane, whose arm was briefly sore. “It was a dramatically different experience for me,” she said, “I hope that works for others.”

Another group that waited for Novavax are biologists who are excited about its technology. When asked why he opted for Novavax, Florian Krammer, a virologist at the Icahn School of Medicine at Mount Sinai, responded on social network: “As I am a nerd “As for vaccines, I like vaccines produced with insect cells.”

While mRNA vaccines direct the body to produce spike proteins of the SARS-CoV-2 coronavirus, which then train a person’s immune system to recognize and fight the virus, Novavax simply injects the proteins. These proteins are grown inside moth cells in a laboratory, while protein-based injections use mammalian cells.

And Novavax has said that a special ingredient derived from the Chilean soapbark tree improves vaccine potency.

Research suggests the Novavax vaccine is as safe and effective as mRNA shots. Its main disadvantage is arriving late to the scene. Vaccine uptake has plummeted since the first ones became widely available in 2021. Nearly 70% of people received the primary vaccines, compared with less than 20% who opted for the COVID-19 mRNA boosters launched on last year.

The numbers have fallen even further: As of October 17, only 5% of people in the United States have received the latest COVID vaccines, according to the Department of Health.

Daniel Park, an epidemiologist at George Washington University, said low vaccination rates could improve if people who felt unwell after their latest mRNA shots tried Novavax.

The Novamax vaccine protects against serious disease, but researchers are struggling to find out how effective this and other vaccines are, right now, because studies have become complicated to conduct: New coronavirus variants are constantly emerging and people have fluctuating levels of immunity from vaccines and previous infections.

Still, a recent study conducted in Italy suggests that Novavax is comparable to mRNA vaccines. It was still more than 50% effective in preventing symptomatic COVID four months after being administered. Some data suggest that mixing and matching different types of vaccines confers stronger protection, although other studies have found no benefit.

Taking all this into account, Park waited for the Novavax vaccine due to its potentially milder side effects. “Between a demanding full-time job and two young children at home, I wanted to stay operational,” she said. His arm hurt, but he didn’t have the 24-hour discomfort that accompanied his last mRNA injection.

Most people do not have fever after mRNA injections. Even when they do feel it, it is brief and therefore much less harmful than many cases of COVID-19. In fact, most reactions are so minor that they are difficult to interpret. During clinical trials of mRNA vaccines, for example, up to a third of people in the placebo group reported fatigue and headaches after the injection.

People with ME/CFS and long COVID (a potentially debilitating condition that persists months after a virus infection) have responded to COVID vaccines in a variety of ways. Most participants with long COVID in a Canadian study of 83 people said their levels of fatigue, concentration and shortness of breath improved after vaccination. Inflammatory proteins that have been linked to long COVID-19 decreased.

However, larger studies have yet to corroborate this encouraging finding. Dr. Jennifer Curtin, a physician who co-founded a telehealth clinic focused on long COVID and ME/CFS, called RTHM, said vaccines appear to temporarily aggravate conditions for some patients.

To find out how Novavax compares, Curtin posted surveys on social media site X in late October asking whether people with long COVID or ME/CFS felt their symptoms got worse, better, or stayed the same after Novavax. The majority responded: no changes.

“It’s not scientific, but we have to figure it out since these people don’t want to get COVID,” Curtin said. “All my patients are wondering which vaccine to get right now,” he added.

Adding to the uncertainty, the rollout of the Novavax and mRNA vaccines has been bumpy, as pharmacies struggle to predict demand and insurance companies figure out how to reimburse providers for the shots.

Unlike previous vaccine offerings, these options are no longer fully covered by the federal government. A testament to this season’s fight to get vaccinated is that at least one good Samaritan has created an online tool to find open appointments for Novavax.

Buoyed by anecdotes of relief from others with long COVID-19, Hayley Brown, a researcher at the Center for Economic and Policy Research who suffers from the condition, recently opted for Novavax. Unfortunately, his symptoms have worsened. He said temporary discomfort will still be preferable to risking another infection: “As someone with long COVID-19, the thought of getting COVID-19 again is terrifying.”