What happened

Shares of uniQure (QURE -1.30%) climbed 14.61% on Wednesday. The stock closed on Tuesday at $23, then opened on Wednesday at $23.76. It climbed as high as $26.38 before closing the day at $26.36. The stock has a 52-week low of $12.52 and a 52-week high of $30.41; it is up more than 27% so far this year.

So what

The stock jumped after the Food and Drug Administration (FDA), on Tuesday, approved Hemgenix (etranacogene dezaparvovec-drlb), a one-time gene therapy for hemophilia B. It was developed by uniQure, but CSL will commercialize the therapy. It is considered a potential cure for the blood disease and is priced that way -- as much as $3.5 million per dose, making it the priciest therapy yet. Hemophilia B, also known as Christmas disease, is rare. The genetic disorder is caused by a missing or defective factor IX, a clotting protein. The U.S. Centers for Disease Control and Prevention statistics show hemophilia affects roughly 1 in 5,000 births, but only a quarter of those are born with Hemophilia B.

In clinical trials, uniQure said Hemgenix lowered the rate of annual bleeds and that 94% of hemophilia B patients no longer needed factor IX prophylaxis after receiving Hemgenix.

CSL, based in Australia but with offices in King of Prussia, Pa., will commercialize the gene therapy, but uniQure will manufacture it. It has already received $500 million in milestone payments from CSL and will receive up to $1.5 billion more in milestone payments for the drug's approval, along with tiered, double-digit royalties on revenue derived from the therapy. 

Now what

The approval, the first gene therapy approved by the FDA to treat hemophilia B, is a big game-changer for uniQure. In the third quarter, the biotech company's revenue was $1.4 million, down from $2 million in the same period a year ago. The company also lost $47.9 million, or $1.02 in earnings per share (EPS), compared to a loss of $36.5 million, or an EPS loss of $0.79 in the third quarter of 2021. There may be significant pushback because of the therapy's high price, but even at a lower price, it is a big win for uniQure and gives credence to the other gene therapies in its pipeline.