Novavax, following a wait-listed submission of data to FDA last month, announced Monday that Novavax had filed a formal request for an emergency authorization of its protein-based COVID-19 vaccination in the United States.

Novavax’s shots, if approved by the FDA could be the first COVID-19 dosages in America. They are based on the same “protein subunit technology” that has been used for decades for routine vaccinations. Officials believe this option will help convince some vaccine skeptics to get the shots and could also boost the international vaccination goals of the Biden administration.

Novavax’s CEO Stanley Erck stated that the vaccine offered a unique option and could be used as an alternative to existing vaccines in fighting the COVID-19 pandemic.

Novavax’s vaccine is for adults 18 years and older. The percentage of Americans who have not been vaccinated is decreasing. According to the Centers for Disease Control and Prevention, close to 90% of Americans have received at least one dose COVID-19 vaccine.

Most of the population was vaccinated using mRNA-based vaccines, such as those developed by Moderna, Pfizer or BioNTech. These vaccines have been proven safe and effective in reducing COVID-19 deaths and cases among millions of Americans.

Federal health officials have said for years that protein-based vaccines may still be eligible for authorization in an effort to persuade those who are unable or unwilling to accept the mRNA shots.

“Some people in the United States are still refusing to take our mRNA vaccines, and they are waiting on a protein-based vaccine. We need to do everything we can to get more people vaccinated,” Dr. Peter Marks, an FDA top vaccines official, stated at a conference last January.

A spokesperson for the FDA did not comment on whether it would convene a meeting with its outside vaccine experts, The Vaccines and Related Biological Products Advisory Committee before deciding whether Novavax shots will be authorized. This was similar to what happened for the Pfizer BioNTech, Moderna and Johnson & Johnson vaccines.

Before the first doses of Novavax’s COVID-19 vaccination can be distributed, both the FDA and Centers for Disease Control and Prevention have to approve it.

Two vaccines, Novavax and another one developed by Sanofi Pasteur or GlaxoSmithKline are protein-based. They were part of a portfolio of vaccines that was supported by Trump’s Operation Warp Speed in the early stages.

Scientists who develop protein subunit vaccines are not able to inject the whole virus. Instead, they select specific parts of the virus and trigger an immune response. This technique has been used in vaccines for hepatitis B and pertussis (whooping cold) and other diseases for many years.

Novavax’s protein vaccines can also be combined with adjuvants, which can help to stimulate an immune response.

This is in contrast to the mRNA vaccines and Johnson & Johnson’s Janssen virus vector vaccine. These vaccines work by getting some cells to produce a harmless amount of SARS-CoV-2 (the virus that causes COVID-19), to trigger an immune response.

Novavax’s shot has been approved in many countries, including Australia and South Korea. The World Health Organization has approved the vaccine, which was manufactured at sites in India and Europe.

Novavax has published results that show the vaccine is safe and effective in preventing infections, around 90% in total. These findings were based on clinical trials in North America and Britain earlier in the pandemic. Novavax claims its vaccine should be effective against the Omicron variant. This is based on data from booster studies and adolescents.

The submission was submitted later than originally planned. Novavax stated to investors last May that it expects to file for FDA authorization in the third quarter 2021. The company revealed that the Biden administration had stopped funding Novavax’s production until the FDA could reach an agreement over its “analytical methods”.

At the end of December, the company submitted its final data regarding its manufacturing activities to FDA.

Officials from the State Department say that Novavax could be used to vaccinate Americans. They also advocated for Novavax production expansion in order to reach international vaccine donation goals.

“Novavax, another big, huge variable at this stage, and I think if Novavax arrives fairly soon that will be wonderful, and that will be a huge help because they are a major part the COVAX portfolio,” Jeremy Konyndyk of the U.S. Agency for International Development’s COVID-19 taskforce, said to reporters in October.