FDA advisory to weigh risks and benefits of Novavax’s COVID-19 vaccine



After more than a year with the use of two types of COVID-19 vaccines in the United States, one will be considered by the US Food and Drug Administration next week.

FDA’s Vaccine Advisor ready to meet on tuesday For the nation to consider Novavax’s coronavirus vaccine.

Based on data included in an agency Briefing document posted on Friday, an FDA review found that the vaccine efficacy against mild, moderate or severe COVID-19 was 90.4% for a period of 2½ months after completing a two-dose primary series. The document notes that, in a primary analysis, the vaccine’s effectiveness fell to 78.6% in adults age 65 and older.

Those efficacy numbers were collected prior to the emergence of the Omicron coronavirus variant. It is not clear how long the protection lasts or how well the vaccine will protect against Omicron.

In An announcement published in DecemberThe company reported that the vaccine had “extensive cross-reactivity against Omicron and other circulating variants from a primary 2-dose regimen, with responses increasing after the third dose at six months.”

Novavax’s vaccine, called NVX-CoV2373, is given as two doses three weeks apart for the primary vaccination series.

Although most adverse reactions to the vaccine were mild to moderate and lasted only a few days, the FDA described rare events of myocarditis and pericarditis — inflammation of the heart muscle and tissue surrounding the heart — associated with the vaccine.

The FDA’s briefing document states, “Several incidents of myocarditis/pericarditis were reported in association with NVX-CoV2373 administration, similar to myocarditis following mRNA COVID-19 vaccines and NVX-CoV.” 2373 Causal relation to concern.”

The document describes six cases that occurred after vaccination with Novavax. Among the men aged 16 to 67, there were five. Five of the six cases were hospitalised, but have since recovered.

An increased risk of myocarditis and pericarditis has been identified in people who received the mRNA Pfizer/BioNTech and modern COVID-19 vaccines now used in the United States.

In a statement on Friday, Novavax addresses heart inflammation concerns Specifically: “We learned that we can expect to see natural background incidence of myocarditis in any sufficiently large database, and that young men are at greater risk. Myocarditis is often due to non-specific viral infections.” It happens.” It said the rates of myocarditis in the vaccinated participants were similar to those in the placebo group.

“We believe there is insufficient evidence to establish a causal relationship. We will continue to monitor all adverse events, including myocarditis and pericarditis,” the company said.

The most common adverse reactions to the vaccine were injection site pain, fatigue, headache, and muscle pain. Reactions were more commonly reported in younger participants in vaccine clinical trials.

In its briefing document, the FDA summarized, “The known benefit among those receiving the vaccine, relative to placebo, among those 18 years of age and older is mild to severe COVID-19 occurring at least 7 days after second primary series vaccination.” There is a reduction in the risk of 19.”

At Tuesday’s meeting, members of the FDA’s Vaccine Advisory Committee will vote on the question: “Based on the totality of the available scientific evidence, determine the benefits of the Novavax COVID-19 vaccine when for use as a 2-dose series.” exceed the risks. Persons 18 years of age and older?”

In late January, Novavax announced that it had submitted a request to the FDA to authorize its coronavirus vaccine for emergency use in the United States.

In November, Indonesia became the first country to grant emergency use authorization for Novavax’s vaccine. It has since been authorized in other countries including the European Union, the United Kingdom, Canada, South Korea, Australia, India, the Philippines and New Zealand.

Even though most adults in the United States have been vaccinated against COVID-19, the company’s chief has said it sees Novavax’s vaccine as a potential alternative to a booster dose, regardless of a person’s initial dose. What type of vaccine was given for

Novavax’s vaccine was developed as a protein subunit vaccine, a more traditional type of technology than the mRNA used for Moderna and Pfizer vaccines. other Examples of Subunit Vaccines There are vaccines for hepatitis B and pertussis.

“We believe our vaccine provides a differentiated alternative built on a well-understood protein-based vaccine platform that can be an alternative to the portfolio of available vaccines,” said Novavax’s CEO. Stanley Erk said in a statement: In January.

Novavax’s protein-based coronavirus vaccine relies on recombinant nanoparticle technology and Novavax’s adjuvant, called Matrix-M, to stimulate an immune response and high levels of neutralizing antibodies.

Protein-based vaccines such as Novavax work by making the body’s immune system recognize small modified pieces of the virus it is targeting. In Novavax’s case, that means fragments of the coronavirus spike protein.

When the genetic sequence of the virus that causes COVID-19 was published, scientists around the world quickly identified it as a coronavirus because “spike protein“on its surface. These spikes form large protrusions, making the coronavirus appear to be wearing a crown, and the “corona” is Latin words for “crown”

Scientists at Novavax identified the gene for the spike protein and created a modified version of that gene. The researchers cloned the gene into a baculovirus that infects insects. They then infected insect cells – specifically, cells from the fall armyworm – prompting them to produce the coronavirus spike protein.

These virus-like nanoparticles were harvested to make Novavax’s vaccine.

“The whole idea of ​​a vaccine is to show the immune system something that looks, tastes and acts like a virus, with the exception that it doesn’t make you sick. So we created the spike protein. We put it in a single particle. — basically, like a soap bubble — and it’s shaped like a virus,” said Dr. Gregory Glenn, president of research and development for Novavax, told CNN last year,

“It is not contagious. We never touch the coronavirus itself,” Glenn said. “Then that is given to people, and they have an immune response that is very much focused on the spike – and I would say, our The hallmark of the vaccine is that it elicits a very strong immune response with very few side effects, and the dosage is very low and the vaccine can be stored with normal refrigerated temperatures.”

As Novavax seeks authorization for emergency use of its NVX-CoV2373 vaccine, it is also studying a different vaccine that specifically targets the Omicron variant called NVX-CoV2515. The company announced this week that it has started Phase 3 trial of this vaccineTo assess its safety and efficacy as a booster shot.

“The trial will seek to determine antibody responses to a bivalent vaccine containing both NVX-CoV2373 and NVX-CoV2515, which have received a booster series of mRNA vaccines,” Novavax said in a news release.

The trial will analyze an Omicron-specific vaccine and a bivalent vaccine in more than 1,000 participants in Australia.

Two doses of either the Omicron-specific vaccine or the original NVX-CoV2373 vaccine will be given after three doses of Pfizer-BioEntech and/or Moderna Vaccine, which participants received at least three months prior to participation in the trial.

Similarly, two doses of either the Omicron-specific vaccine or the original NVX-CoV2373 would be given after two doses of mRNA vaccine received at least six months prior to entry into the trial.

Participants who have been vaccinated with three doses of mRNA vaccine at least three months before entry into the trial will be given two doses of the bivalent vaccine.

The trial will last about 10 months, and preliminary results are expected in the second half of this year.


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