Thanks to COVID-19 vaccines, weve been able to see loved ones more often with less fear and experience less intense symptoms . However, the pandemic is far from over, with cases continuing to spike in large waves , people dealing with long COVID and more.

As scientists and health experts continue to learn how to fight the virus, more treatment and prevention methods are becoming available including additional vaccines. This week, a Food and Drug Administration advisory committee voted unanimously to recommend Novavaxs COVID-19 vaccine. Should it get the green light from the FDA and the Centers for Disease Control and Prevention, the shot could be cleared for emergency authorization use in the coming days.

So why is a new shot being authorized when there are millions of unused COVID vaccines expiring on shelves ? Will this new vaccine move the needle in the pandemic?

Heres what experts think about it and everything else you need to know:

How does the Novavax vaccine work compared to the other vaccines?

Unlike the Pfizer, Moderna and J&J vaccines the first two which are mRNA-based, and the latter of which is viral vector-based Novavaxs is protein-based.

Novavaxs COVID-19 shot is a technology commonly used in most other vaccines, such as flu, hepatitis B and shingles, said Dr. Mahdee Sobhanie , an infectious diseases physician at Ohio State University Wexner Medical Center. The protein, which is selected in this case for the Novavax vaccine, is the spike protein found in COVID-19.

When your body recognizes the protein, it prepares to fight it. The persons immune system does the rest by recognizing the foreign (i.e., nonhuman) protein and producing antibodies to block it, explained Dr. David Diemert , the clinical director of George Washington Universitys Vaccine Research Unit.

The Novavax vaccine also has an adjuvant, or additive, that helps increase the immune response to the protein, according to Diemert. He called it more of a traditional vaccine since some older vaccines are also protein-based.

The Novavax COVID-19 vaccine is a two-shot regimen given 21 days apart. As far as boosters go, Sobhanie said hes not sure if one will be needed to fight against future variants or not, given the limited data.

Diemert believes a booster may be needed. Based on the decrease in antibody levels over time after the two injections of the Novavax vaccine, and the appearance of new variants , it is possible that booster doses will be needed to maintain immunity, he said.

Is the Novavax vaccine effective at fighting off COVID and does it work better than other ones that are already available?

According to 2021 data , prior to the omicron variant becoming the dominant strain, Pfizer was about 95% effective in protecting people from symptomatic COVID-19 after they first get the shots; Moderna was 94.1% effective and J&J was 66% effective. (As we now know, the vaccines have been less effective against omicron at preventing symptomatic disease, and the antibodies gained from the shots do wane over time. A booster increases our protection. All the vaccines drastically reduce the risk of severe disease and death.)

When tested last year, Novavax was 90.4% effective in protecting people against symptomatic COVID-19 and 100% effective in protecting people against moderate to severe COVID-19 after people got the shots. So, the number is slightly lower for mild COVID-19 cases but not one to be ignored, especially with the benefits well discuss in a bit.

Novavax has been used in other parts of the world and has emergency use authorization from both the European Union and World Health Organization, Sobhanie added.

But can it protect us against new variants, like omicron , and its subvariants like BA.2 and BA.4? Experts are still gathering information there. Those trials were mostly done before the appearance of the delta and omicron variants, so the efficacy against those isnt known, Diemert explained.