What happened

Shares of Novavax (NVAX -0.95%) were jumping 9.7% as of 10:48 a.m. EDT on Thursday. There were a couple of catalysts for the stock.

Novavax and its partner, Serum Institute of India, announced Thursday morning that they have filed for World Health Organization emergency use listing of Novavax's COVID-19 vaccine. Also, data from a late-stage clinical study conducted in the U.K. of the vaccine were published in The New England Journal of Medicine. This data showed that Novavax's vaccine achieved an efficacy of 89.7%.

Gloved hands holding a vaccine vial with a syringe and needle.

Image source: Getty Images.

So what

Neither of today's developments was a surprise. However, they were both positive for Novavax and motivated some investors to pile back into the vaccine stock

Of the two stories, the EUL filing is the more important for Novavax. An EUL from the WHO is needed to export vaccines to countries that participate in the COVAX Facility. Novavax CEO Stanley Erck stated, "Today's submission of our protein-based COVID-19 vaccine to WHO for emergency use listing is a significant step on the path to accelerating access and more equitable distribution to countries in great need around the world."

Now what

It's uncertain how long the WHO will take to complete its review of Novavax's and SII's EUL filing. In the meantime, investors can look forward to several other key milestones. Novavax is preparing to file for emergency use authorizations in several countries, including the U.K., Canada, Australia, New Zealand, the European Union, and the U.S.