Shares of cancer-detection firm Grail (GRAL 4.29%) fell by half in last Friday's trading session. That's quite a turnabout after the company's share price more than quintupled in 2025, from about $19 a share in January to $110 in November.
Last week shares of the California-based biotech were trading at around $102. Today they're priced at $49. What happened?
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Well, Grail makes a multi-cancer early detection test called Galleri that screens for a signal in the blood shared by more than 50 types of cancer. Cancers growing in the human body shed their DNA into the bloodstream, and the Galleri test can detect that DNA very early on -- hopefully, early enough for effective treatment.
If that sounds like an incredible innovation in the world of cancer detection, that's because it is. But investors need to know that the test works and can reduce late-stage cancer diagnoses. On Thursday the company announced that, in a large clinical trial in England, the Stage III-IV cancer reduction goals were not met. According to a Grail press release, "The primary endpoint of statistically significant Stage III-IV reduction was not observed."

NASDAQ: GRAL
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Grail has been working hard to get the U.S. government to cover its Galleri test under Medicare -- the holy grail for any healthcare treatment or test. It's not clear now if that goal is less achievable. But it is clear that Galleri will have to perform better in other trials. Until that happens, the company's share price will linger at a much lower level than it recently enjoyed.





