Novavax finally submits its COVID-19 vaccine to the FDA. Is it too late?

It's finally here: After a series of delays in the lead-up to Novavax's COVID-19 vaccine filing with the FDA, the biotech has completed its emergency use authorization request.

Novavax on Monday said it filed NVX-CoV2373 for use in people 18 and older. NVX-CoV2373 is a protein-based shot that has demonstrated efficacy of about 90% against symptomatic disease in a large trial in the U.S. and Mexico, the biotech says.

Still, it's not clear what level of use the vaccine will see in the U.S., which has relied mostly on the mRNA shots from Pfizer and Moderna.

For its EUA submission, Novavax included a range of preclinical, clinical and manufacturing-related data. The submission comes after several delays and missed deadlines in Novavax's quest to advance the shot to the key U.S. market. 

Novavax originally hoped to file its EUA by the second quarter of last year, but it had to push that deadline to the third quarter thanks to a manufacturing glitch. Then in October 2021, the biotech said it was eyeing an end-of-year filing.

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Earlier this month, the company said it was nearly ready to file, but that it would need until the end of January for the official EUA request. Just in time for that deadline, Monday's filing came during the last day of January.

Amid the FDA delays, the company has scored a conditional marketing authorization from regulators in Europe and an emergency use listing from the World Health Organization. The shot also has emergency nods in Indonesia and the Philippines.

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Thanks to the delays, it's not clear what kind of use the Novavax shot will see in the U.S. In a statement to The New York Times, Novavax's CEO Stan Erck said the company is working with officials “to develop a plan which includes doses, manufacturing, timing and ongoing clinical trial research for boosters and pediatrics to support their pandemic response.”

As the FDA reviews existing data on the program, Novavax is running additional studies to learn more about the shot. The company's PREVENT-19 trial, which enrolled about 30,000 people in the U.S. and Mexico, is testing a third, booster dose. Meanwhile, investigators are also running a study of the Novavax vaccine in adolescents ages 12 to 17.