What happened

Shares of Dynavax Technologies (DVAX -0.85%), a small biopharmaceutical company struggling to launch a new hepatitis B vaccine and develop a new cancer therapy, fell 19% in December, according to data from S&P Global Market Intelligence. It was a quiet month for Dynavax, but a general market panic dragged the Nasdaq Biotechnology Index 11% lower. 

Check out the latest Dynavax Technologies earnings call transcript.

So what 

Dynavax is more sensitive to market pressure than its peers right now because its first drug launch isn't going very well. The FDA approved Heplisav-B in 2017, but sales during the first nine months of 2018 tallied just $2.9 billion.

Person in a suit drawing a downward sloping chart.

Image source: Getty Images.

The company has an experimental new cancer therapy in development that produced impressive tumor response data early on, but mixed results from an ongoing study are making investors nervous.

Now what

Independent drug launches generally don't perform as well as those with big pharma backing, but Hepislav-B is showing signs of life. Sales in October exceeded the entire first nine months of 2018.

Investors probably don't want to let go of these shares until we hear what the CEO has to say about the year ahead on Thursday, Jan. 10, at the J.P. Morgan Healthcare conference.