What happened

Aurinia Pharmaceuticals Inc. (AUPH -0.17%) shares continued a months-long slide, falling 16.1% in December according to data from S&P Global Market Intelligence. Despite the clinical-stage biotech's addition to the index by the iShares Nasdaq Biotechnology Index last month, a relative lack of interest allowed the price to slide even further.  

So what 

Last March, Aurinia Pharmaceuticals stock soared when the biotech's lead candidate, voclosporin, smashed through its main goal in a clinical trial with lupus nephritis (LN) patients. The company thinks there are at least 125,000 LN patients in the U.S., many of whom are underserved by standard treatment, which involves poorly tolerated steroids.

Downward sloping chart on chalkboard.

Image source: Getty Images.

If successfully launched, voclosporin could generate sales well over $1 billion per year. That's worth getting excited about, but the company doesn't expect to complete enrolling patients in an ongoing 52-week pivotal trial until the second half of the year. Given the lack of significant events, last month's slide looks like a simple case of boredom.

Now what

Aurinia finished last September with $182.4 million after losing $13.2 million in the third quarter. Management believes that's enough to carry the company into 2020 before it needs to raise capital again. I think that might be a bit too optimistic.

In October, Aurinia announced plans to expand voclosporin's clinical development program to include a handful of rare conditions that affect perhaps 150,000 patients globally. The increased clinical trial activity won't come cheap, and investors will want to keep a close eye on the company's cash burn rate going forward.