The Food and Drug Administration (FDA) and Novavax logos are seen on the back of a medical syringe and vials in this photo illustration.
Pavlo Gonchar | LightRocket | Getty Images
of novavax COVID-19 The vaccine will face scrutiny from independent vaccination experts from the Food and Drug Administration this week, a significant move toward US regulatory authority two years after the Maryland biotech company received taxpayer funding to develop the shots.
The committee of vaccine experts will weigh the safety of Novavax’s shots and their effectiveness in preventing covid during an all-day public meeting on Tuesday. If the committee supports the vaccine, the FDA will certainly give the green light for a dose in the US from Serum Institute of India, manufacturing partner of Novavax. The company’s shots are authorized in 41 countries outside the US, including Australia, Canada. and the European Union.
“We feel very confident in the data we have collected,” said Novavax spokeswoman Sylvia Taylor. “If past success is any indication of future success, we feel really good,” Taylor said.
Novavax was an early participant in the US government’s race to develop a vaccine against COVID in 2020, receiving $1.8 billion from Operation Warp Speed. However, the small biotech company faced an uphill battle to increase its manufacturing capacity and its clinical trial data. came Later than Pfizer and Moderna, which developed their shots at breakneck speed, are now major players in the US vaccination campaign.
When the pandemic began in 2020, Novavax had 100 employees and no manufacturing capacity, said John Trizzino, the company’s chief commercial officer. Today, the company has the capacity to produce 2 billion doses per year, Trizzino said.
Novavax’s shots are based on a protein technology used for decades in the hepatitis B and HPV vaccines. pfizer‘sand modernK shots, on the other hand, were the first vaccines to use messenger RNA technology to receive FDA approval. Novavax believes it could reach people who have not yet been vaccinated, as they would prefer to receive a shot based on technology that has a long track record, Taylor said.
Protein vs. mRNA
The shots from Pfizer and Moderna rely on messenger RNA to turn human cells into factories that make copies of Covid’s spike protein to induce an immune response that fights the virus. The spike is the part of the virus that attacks and invades human cells.
In contrast, Novavax causes the virus to spike outside the human body. Spike’s genetic code is put into a baculovirus that infects moth cells, which then produce copies of the spike which are then purified and extracted. The spike copy, which cannot replicate or cause COVID, is injected into people producing an immune response against the virus.
Chief medical officer Philip Dubowski said manufacturing the spike protein outside the human body allows the company to ensure that the vaccine is configured in a way that is most effective at generating an immune response.
“We know exactly what we’ve made and we test it as part of the vaccine release process to make sure it’s in the right composition,” Dubowski said.
The vaccine also uses an adjuvant, an extract purified from the bark of a tree in South America, to induce a broader immune response. Adjuvants have been used in licensed vaccines against malaria and shingles. Shots contain 5 µg of spike copy and 50 µg of adjuvant.
Novavax Vaccine Efficacy
Novavax’s two-dose vaccine for adults 18 years of age and older was 90% effective in preventing disease from covid, and 100% effective in preventing serious illness, according to results from the company’s clinical trials in the US and Mexico . Those results are just as good as early test results from Pfizer and Moderna in 2020.
However, the pandemic and public health response is in a very different place today than in 2020, which presents Novavax with immediate challenges if the FDA authorizes its vaccine. About 70% of people eligible for vaccination in the US have already received their first two doses, along with shots from Pfizer or Moderna. And the world is now battling the Omicron variant, which is very different from the original strain of the virus that emerged in Wuhan, China, in late 2019.
The adult trial of Novavax was conducted from December 2020 to September 2021, before the Omicron version went into effect. According to FDA briefing documents published ahead of Tuesday’s committee meeting, there are no data available to assess Novavax’s effectiveness against Omicron, which continues to mutate into more permeable versions of the virus. However, FDA officials said the two-dose vaccine would be more likely than not to provide meaningful protection against serious disease.
Novavax published a laboratory study in December showing that people who received two doses had an immune response against Omicron, although antibodies that prevented infection were about four times lower than those in the original Wuhan strain of the virus. Have become. However, according to study data, a booster increased protective antibodies against Omicron by about 20-fold, compared to the peak response from the first two doses against the Wuhan strain. Higher antibody levels suggest, although not a guarantee, that a third dose will provide a higher level of protection.
Although much of the US population has already been vaccinated, Novavax officials believe the company’s shots could play an important role as a booster for adults and the primary immunization for teens 12 to 17 years old. . Right now, only Pfizer’s vaccine is available for teens, although the FDA will review Moderna’s shots for that age group on June 14. According to the Centers for Disease Control and Prevention, about 50% of adults have not yet received a third shot, and 40% of teens are not fully vaccinated.
To be clear, an FDA committee is reviewing Novavax’s two-dose primary series for adults only on Tuesday. However, Novavax plans to ask the FDA to authorize a third dose for adults as well as a primary series for teens 12 to 17 if the agency approves two doses for adults, Taylor said. Novavax is also studying a third shot for teens.
heart palpitations concern
According to FDA briefing documents, the most common side effects of shots of Novavax were injection site pain, fatigue, headache and muscle aches. However, according to the FDA, four participants developed inflammation of the heart, either myocarditis or pericarditis, or unusual chest pain after receiving shots of Novavax. They all remained hospitalized for several days, although they recovered.
“These events raise concern for a causal relationship with this vaccine, as documented with mRNA COVID-19 vaccines,” FDA officials said in the briefing documents. Second doses of Pfizer and Moderna’s vaccines have been associated with an increased risk of heart inflammation in young men and teenage boys.
Novavax said in a statement that there is not enough evidence to establish a causal relationship between the vaccine and heart inflammation. However, the company said it would continue to monitor for myocarditis and pericarditis during its trials.
Fall Booster Campaign
It is unclear how many doses of Novavax will be available in the US if the FDA authorizes the vaccine this week. Novavax initially agreed to supply 100 million doses to the US under its $1.8 billion Operation Warp Speed contract, but used some of the money to support studies on the company’s third dose and vaccines for children. has gone.
Trizzino said the initial delivery of the shots would be done in the weeks following FDA authorization, without specifying an amount. He said Novavax and the US government have not yet reached an agreement on future orders.
Trizzino said Novavax is seeing demand for a vaccination campaign in the US at a time when public health officials expect another wave of Covid infections as people spend more time indoors when the weather changes. The FDA is considering switching all COVID vaccines to target the Omron variant before the fall to increase the shots’ effectiveness against mild disease.
Novavax began clinical trials in late May to study one shot that targets Omicron alone and another that includes both the Wuhan and Omicron strains. However, the deadline for updating vaccines for the fall is short. Independent experts from the FDA are holding their second meeting on June 28 to discuss whether a strain switch is needed, leaving just a few months for Novavax and other vaccine makers to manufacture the updated shots.
Trizzino said the path to a vaccine based on either the Wuhan strain alone or the Omicron variant for the fall is relatively straightforward, but producing shots that include both strains is more challenging under a compressed schedule. While it’s not clear what the FDA will decide for the fall, COVID vaccines — whether they’re based on Wuhan or Omicron or both — will be needed well beyond this year, Trizzino said.
“This virus is not going to go away anytime soon,” Trizzino said. “There is certainly a high degree of certainty that this will be some sort of annual reversion in the near future,” he said.