What happened

Shares of Moderna (MRNA -0.74%) and BioNTech (BNTX -1.44%) fell 5.2% and 7.5%, respectively, on Monday after rival COVID-19 vaccine maker Novavax (NVAX -0.43%) announced favorable clinical trial results. 

So what 

Novavax's vaccine candidate, NVX-CoV2373, demonstrated overall efficacy of 90.4% in a phase 3 study with nearly 30,000 participants. The drug was also shown to provide 100% protection against moderate and severe forms of COVID-19. Additionally, it was generally well-tolerated among the trial's participants.

"These data show consistent, high levels of efficacy and reaffirm the ability of the vaccine to prevent COVID-19 amid ongoing genetic evolution of the virus," Novavax president of research and development Gregory Glenn said in a press release.

A person in medical gear is holding a drug vial labeled coronavirus.

Image source: Getty Images.

These results are close to those that were achieved by the Moderna and Pfizer/BioNTech vaccines. Novavax could thus emerge as a formidable new competitor to the leading COVID-19 drugmakers. "Our vaccine will be a critical part of the solution to COVID-19," Glenn said.

Now what

Novavax intends to file for regulatory authorizations in the third quarter. The biotech said it could manufacture 150 million doses per month by the end of this year.

While some countries, such as the U.S., have already acquired the vaccine doses they need, many other countries have yet to do so. Novavax could thus see strong demand for its vaccine in international markets -- and potentially wrestle away some market share from Moderna and BioNTech.