Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of biotech Dynavax Technologies (NASDAQ:DVAX) jumped as much as 20% today, and finished up 13%, after positive results on its Hepislav vaccine.

So what: The FDA said today that the vaccine works on Hepatitis B, and that it's more effective than GlaxoSmithKline's (NYSE:GSK) Engerix-B. The agency has an advisory panel meeting set for November, and will decide on its approval on February 24. One analyst, Katherine Xu, of William Blair & Co., estimates that the drug could generate as much as $775 million in annual sales at its peak.

Now what: Based on the modest bounce in the stock, investors seemed to be expecting a positive outcome here. Assuming Hepislav gets approved and makes the projected levels of sales, the stock looks poised to climb, considering the company's market cap is still under $1 billion, and it has a pipeline with potential treatments for diseases such as the flu, asthma, and Hepatitis C.

Don't miss your next dose of Dynavax.

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