An Overview of the Novavax COVID-19 Vaccine

Novavax is a Maryland-based biotech company. It's taking a traditional approach to developing a vaccine against COVID-19.

The company began a Phase 3 trial of its vaccine candidate, NVX‑CoV2373, in the United Kingdom in September 2020. This was followed by a second Phase 3 trial in the United States and Mexico in December 2020. These two late-stage trials enrolled a total of almost 45,000 people.

This put Novavax behind its competitors, but early results show promise. The company announced the vaccine was 90% effective overall in the Phase 3 trials. And it was 100% effective against moderate and severe disease.

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How It Works

The Novavax vaccine uses a custom-made spike protein that mimics the natural spike protein in the SARS-CoV-2 virus. Novavax has for years worked on developing its recombinant nanoparticle technology, and created the first COVID-19 vaccine using this method in the spring of 2020.

By summer 2020, early clinical trials showed that the vaccine appeared to be safe, and more advanced trials entered the planning stage in the United States and other countries.

The two-dose vaccine works by introducing a protein that prompts an antibody response, which blocks the ability of future coronavirus to bind to human cells and prevents infection. The protein is combined with Novavax's Matrix-M adjuvant, which is important in enhancing the immune response elicited by the protein antigen.

How Effective Is It?

Early vaccine trial results published by Novavax revealed a strong antibody response to the vaccine in animals. By August 2020, early human trials showed strong antibody responses with no serious adverse events and few side effects.

Novavax announced on June 14, 2021, that the vaccine was 90.4% effective in a preliminary analysis of data from its Phase 3 trial in the U.S. and Mexico. It was also 100% effective against moderate and severe disease. The trial was conducted when the U.K. variant B.1.1.7, also known as the Alpha variant, was the predominant strain in the U.S.

This followed an announcement in late January that the vaccine was found to be 89.3% effective in its U.K. Phase 3 trial and included protection from the U.K. variant.

The company also announced that the vaccine was 60% effective in a Phase 2b clinical trial in South Africa and included protection from the South African variant B.1.351, also called the Beta variant.

In Novavax's trial, participants were not directly exposed to the virus, but instead researchers used a natural infection approach. This method was also used for the three COVID-19 vaccines that received emergency use authorizations (EUAs) from the Food and Drug Administration (FDA).

When Will It Be Available?

Novavax's vaccine candidate generated a lot of interest because early animal study data showed that it was highly effective at preventing replication of the coronavirus in nasal passages. It was an important development for COVID vaccines since it suggested that it may help reduce both infection and transmission rates.

Novavax also relies on an established vaccine delivery method and can be stored at standard refrigerator temperatures.

However, Novavax was behind its competitors when it came to clinical trials so even though it continues do well, the two-dose vaccine may not be available until late 2021.

The company itself also faces significant challenges since 2019 was a difficult year for Novavax. Science magazine reported that the company sold some of its manufacturing facilities and has to rely on more contractors to manufacture many of its vaccines. This could delay production.

The company announced that it plans to apply for authorizations in the third quarter of 2021 and has a manufacturing capacity of 100 million doses per month by then and 150 million doses per month by the end of 2021.

Who Can Get the Novavax Vaccine?

Like other COVID-19 vaccine candidates, the Novavax vaccine has been tested in adults aged 18 and up.

The company announced on June 14, 2021, that it completed enrollment of 2,248 adolescents in its Phase 3 trial in adolescents ages 12 to 17. Novavax has not provided updates on trials in younger children.

Information hasn't been provided yet on concerns for specific groups.

If the vaccine is authorized by the FDA, any doses purchased by the U.S. government will be free to its citizens. While the vaccine itself is free, the facility or agency that offers the vaccine may seek reimbursement for administration costs from heal insurance plans or public health programs. However, no one receiving a vaccine can be charged any fees.

Side Effects and Adverse Events

No serious adverse events were reported in early trials of the Novavax vaccine, but more information will be available after the late-stage trial results are published. In Phase 3, adverse events "occurred at low levels and were balanced between vaccine and placebo groups." according to Novavax.

The most common side effects, according to Novavax:

  • Injection site pain and tenderness
  • Fatigue
  • Headache
  • Muscle pain

Injection site pain lasted less than three days and fatigue, headaches, or muscle pain lasted less than two days in the Phase 3 trials.

Funding and Development

Novavax has been awarded more than $2 billion globally for its efforts to develop a COVID-19 vaccine, with $1.6 billion from the U.S. government alone. The U.S. funds were given as a part of Operation Warp Speed and from the Biomedical Advanced Research and Development Authority (BARDA). BARDA is a program that falls under the U.S. Department of Health and Human Services. This program and Operation Warp Speed sought to speed up how quickly vaccines to fight COVID-19 can be developed and approved for use.

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8 Sources
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