What happened Shares of Novavax, Inc. (NASDAQ: NVAX), a clinical-stage biotech focused on novel vaccine development, jumped 24.6% higher as of 11:50 a.m. EDT on Tuesday. Investors are cheering in response to the company's announcement that it will hold a conference call next week to discuss recent progress with its RSV F vaccine. So what The respiratory syncytial virus sends a staggering number of older adults and infants to hospitals each year, but a vaccine that effectively prevents infections has yet to emerge. Novavax came awfully close with a mid-stage study that just crossed the threshold for statistical significance, but the stock cratered last year when the RSV F vaccine couldn't repeat the success in a larger study. Image source: Getty Images. An effective RSV vaccine could easily generate several billion in annual sales, and investors send this stock jumping at the slightest hint an application for approval of its candidate might eventually reach the Food and Drug Administration. Today's jump isn't in response to any actual data, at least not yet. Simply announcing a call to discuss top-line data from a mid-stage clinical trial is enough to ignite hope. Now what On July 24, 2017, management intends to present results from the phase 2 safety and immunogenicity trial with its RSV F vaccine in adults over 60 years of age. While the call will be worth a listen, it won't tell us a great deal about the candidate's chances of eventually earning an approval. Previous studies have already shown the vaccine is safe and that it stimulates immune systems to create RSV-fighting antibodies. In a rational market, the only data that would inspire a stock movement like the one we've seen today would be results from the ongoing, late-stage maternal immunization study. Investors better settle in for a long wait. According to today's announcement, the pivotal trial, which involves dosing women while they're pregnant and then measuring RSV infection rates among their babies, is still enrolling patients.10 stocks we like better than NovavaxWhen investing geniuses David and Tom Gardner have a stock tip, it can pay to listen. After all, the newsletter they have run for over a decade, Motley Fool Stock Advisor, has tripled the market.* David and Tom just revealed what they believe are the 10 best stocks for investors to buy right now... and Novavax wasn't one of them! That's right -- they think these 10 stocks are even better buys. Click here to learn about these picks! *Stock Advisor returns as of July 6, 2017Cory Renauer has no position in any stocks mentioned. The Motley Fool has no position in any of the stocks mentioned. The Motley Fool has a disclosure policy.