NovavaxNovavax (Nasdaq:NVAX) has won unanimous backing from the FDA’s Vaccines and Related Biological Products Advisory Committee (VRBPAC) for its NVX-CoV2373 COVID-19 vaccine.

Voting 21 to 0 with one abstention, the VRBPAC recommended that FDA grant emergency use authorization (EUA) to the vaccine for adults 18 and older.

The Novavax would be the fourth vaccine to win authorization in the U.S., following the vaccines from Johnson & Johnson, Moderna, and Pfizer and its partner BioNTech.

The vaccine is likely to win authorization by June, estimated M. Nielsen Hobbs, an analyst for Informa Pharma Intelligence.

While several companies are reading next-generation COVID-19 vaccines, the Novavax vaccine is “not so much a new entrant as a much delayed initial entrant as part of Operation Warp Speed,” Hobbs said.

If it wins authorization, the Novavax vaccine would be the first protein-based COVID-19 vaccine in the U.S.

At present, roughly 30% of Americans remain unvaccinated.

Demand has fallen for the Johnson & Johnson vaccine after federal authorities have recommended constraining its use.

While the NVX-CoV2373 vaccine is protein-based and thus has a similar profile to traditional vaccines for influenza, hepatitis B, shingles and other diseases, it remains unclear how much demand there will be for the new vaccine.

As COVID-19 vaccines and boosters have become available to an incrementally larger swath of the population, the demand for the shots has fallen. “With each new iteration, whether via the third dose or the second dose in the younger kids, a smaller and smaller percentage of people got jabs,” Hobb said. “There is a population that was inclined to have gotten their initial shots but didn’t come back for their boosters and didn’t vaccinate their kids.”

After Nasdaq temporarily halted trading of NVAX shares today, the company’s stock price was up 20.57% to $57.48.