What happened

Shares of CymaBay Therapeutics (CBAY 0.03%) were jumping 14.2% higher as of 10:54 a.m. ET on Friday. This move came on the heels of an 8.5% gain on Thursday.

The continued momentum is a result of CymaBay's announcement yesterday of positive top-line results from a late-stage clinical study evaluating experimental drug seladelpar in treating primary biliary cholangitis (PBC), a rare chronic inflammatory liver disease.

CymaBay reported that seladelpar achieved the study's primary endpoint as well as all key secondary end points.

So what

CymaBay's late-stage results for seladelpar move the company closer to potentially launching its first product. But there are already two approved drugs for treating PBC: ursodeoxycholic acid (UDCA) and Intercept Pharmaceuticals' Ocaliva. 

The great news for CymaBay, though, is that seladelpar appears to have a key advantage over those other PBC treatments. The results from the company's phase 3 study found that it significantly reduced itching, which is a major issue for many PBC patients.

Now what

CymaBay now plans to talk with the Food and Drug Administration, the U.K.'s Medicines and Healthcare products Regulatory Agency, and the European Medicines Agency about regulatory approval filings for seladelpar. Assuming all goes well, it's possible that the company could bring the product to market sometime next year.

Will the biotech stock continue its momentum? That remains to be seen. CymaBay's market cap already stands at nearly $1.7 billion. It could take a while for seladelpar's sales to grow even if it's approved. As a comparison, Intercept projects 2023 sales of Ocaliva between $320 million and $340 million, a level that's taken seven years to reach.