NEW YORK, Feb 20, 2026, 16:53 EST — After-hours
- Grail shares tumbled roughly 50% after a major UK trial failed to meet the primary endpoint for the Galleri blood test.
- Investors are parsing the implications for U.S. regulators, as well as potential Medicare reimbursement.
- The company is planning additional follow-up, with a promise to release more complete data later this spring.
Grail (GRAL.O) plunged roughly 50% to $50.21 after hours on Friday, following news that its key UK trial for the Galleri cancer blood test failed to hit the main endpoint. TD Cowen’s Dan Brennan said Grail should address the mixed results with “proactive, transparent and deliberate” communication about the next steps. 1
The drop’s significant: the NHS-Galleri trial stands as one of the largest real-world examinations yet for “multi-cancer early detection” screening—essentially, a blood test that aims to spot dozens of cancers even before symptoms surface. For investors, the question isn’t just whether these tests detect cancer. They’re watching for evidence they truly shift diagnoses earlier, when patients have a better chance with treatment.
The timing is tricky for Grail. The company is trying to move Galleri into regular medical use, but that depends on whether payers get on board. Medicare coverage stands out as a major hurdle, shaping how reimbursement and physician uptake play out across the U.S.
Grail on Thursday reported selling upwards of 185,000 Galleri tests in 2025, bringing in $147.2 million in revenue for the year. Losses, though, remain substantial. The company wrapped up the final piece of its U.S. FDA premarket approval filing for Galleri in January. It also flagged a new federal law aimed at providing a Medicare reimbursement route for multi-cancer early detection tests. 2
The UK trial aimed for a “primary endpoint”—a statistically significant reduction in stage III and IV cancers combined, which is meant to demonstrate the test can catch disease before it advances to tougher stages. Grail reported the study missed that goal.
According to Morgan Stanley analysts, the market largely anticipated the NHS-Galleri results given how well the stock had performed beforehand. They noted, “not surprised to see shares trading meaningfully lower.” 3
Some bullish investors held on, but sentiment softened. Barron’s pointed to analyst Kyle Mikson, who maintained his buy rating even as he trimmed his price target from $105 down to $80, describing the slide as an “investor overreaction.” The piece also noted that Galleri is priced at $949 and still lacks broad insurance coverage. 4
Grail stuck to its message, highlighting what it called positive signs in the data. “Excited to see the substantial reduction in Stage IV cancer diagnoses,” CEO Bob Ragusa said. The company plans to keep following trial participants for another six to 12 months. Grail also aims to present detailed results at the ASCO 2026 Annual Meeting. 5
The risk is clear enough. Should regulators or insurers zero in on the miss—or press for stronger proof that large-scale screening actually moves the needle—Galleri might hit snags getting widespread reimbursement. That would drag things out, ramp up cash burn. And this stock? It’s already shown it can swing hard on just one data headline.
Right now, traders are bracing for a single setup going into next week: more volatility tied to every fresh analyst reset, and whatever extra guidance management can offer on how the FDA might interpret the UK results alongside the U.S. trial data.
ASCO’s next up, with Grail set to provide fresh details on the NHS-Galleri results; the 2026 event is scheduled for May 29 through June 2 in Chicago. 6
