What happened

The stock of Aurinia Pharmaceuticals (AUPH 1.20%) was surging today after the company's second-quarter earnings call. A positive outlook for Lupkynis, its recently launched drug for lupus nephritis (LN), encouraged investors to drive the stock 21.5% higher as of 1:08 p.m. EDT on Friday.

So what 

All eyes were on Lupkynis sales when Aurinia reported second-quarter results after U.S. markets closed on Thursday. The company didn't disappoint, with product revenue that reached $6.6 million.

Investor examining a stock chart.

Image source: Getty Images.

After first-quarter sales didn't even break $1 million, the uptick in the second quarter allowed Aurinia shareholders to breathe a sigh of relief. Despite today's gains, shares are still trading for a little less than their price over a year ago.

Now what

Systemic lupus erythematosus (SLE) is an autoimmune disorder that leads patients' immune systems to attack their own tissues. SLE affects around 300,000 Americans, and most go on to experience kidney damage, or lupus nephritis.

Lupkynis is the first oral treatment approved by the Food and Drug Administration to treat the underserved LN population, and this isn't the last surge in sales we're likely to see this year. Aurinia is predicting between $40 million and $50 million in Lupkynis sales for all of 2021. As the first available treatment for LN, Lupkynis could go on to generate blockbuster sales for Aurinia and send the biotech stock soaring much higher over the next few years.