TLDR
- Grail (GRAL) stock dropped ~50% in after-hours trading after its NHS-Galleri cancer trial missed its primary endpoint.
- The Galleri blood test failed to show a statistically significant reduction in Stage III-IV cancers across the full trial population.
- A subgroup of 12 deadly cancers did show a favorable trend, with Stage IV diagnoses falling more than 20% in years two and three.
- Grail’s Q4 loss came in narrower than expected at $2.44 per share, with revenue of $43.6 million meeting estimates.
- Grail has submitted a premarket approval application to the FDA, with first-year NHS trial data included in the filing.
Grail (GRAL) stock dropped nearly 50% in after-hours trading Thursday after the company’s landmark NHS-Galleri cancer screening trial failed to hit its primary goal.
The trial, which followed more than 142,000 people in England aged 50 to 77, did not show a statistically significant reduction in Stage III and IV cancers — the key benchmark the study was designed to prove.
That miss was enough to send shares tumbling 48% to $52.25 after the close. In premarket trading Friday, the stock was down around 47% to $53.33. It’s a steep reversal for a stock that had gained more than 200% over the prior six months.
The Galleri test is a blood-based multi-cancer early detection tool that screens for cancers before symptoms appear. Grail has been positioning it as a potential game-changer in cancer screening at a population level.
Where the Data Gets Complicated
While the headline number disappointed, the full picture is more nuanced.
In a pre-specified subgroup of 12 particularly deadly cancers, there was a favorable trend toward fewer Stage III-IV diagnoses. Stage IV diagnoses in that group fell by more than 20% in both the second and third screening rounds.
Adding Galleri to standard care also led to a meaningful reduction in cancers detected through emergency presentation — the kind of late-stage diagnoses tied to higher mortality and greater healthcare costs.
CEO Bob Ragusa called the results “the strongest evidence to date that multi-cancer early detection can shift the stage at which cancers are detected at a population level,” and pointed to PATHFINDER 2 trial results as further support for the company’s direction.
Still, the primary endpoint was not met, and markets responded accordingly.
FDA Filing Already in Motion
Grail filed a premarket approval application with the FDA in January, and the company confirmed that first-year NHS trial data was included in that submission. The outcome of that review now takes on added weight following Thursday’s results.
Additional analyses from the NHS trial are underway. Grail said detailed results will be submitted for presentation at the ASCO 2026 Annual Meeting.
On the earnings side, Grail posted a Q4 loss of $2.44 per share, narrower than Wall Street had expected. Revenue came in at $43.6 million, in line with estimates. The financial results were largely overshadowed by the trial data.
Grail also said it is expanding its field-based sales and medical teams to support growing demand and education efforts around the Galleri test.
In premarket trading Friday, GRAL was down approximately 47% to $53.33.
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