Stock Markets June 1, 2026 08:57 AM

Grail Shares Drop After PATHFINDER 2 Results; Market Reaction Tempered by Mixed Takeaways

Investors sold down Grail stock after the company presented full PATHFINDER 2 data at ASCO showing strong specificity but mixed sensitivity outcomes

By Priya Menon GRAL

Grail Inc. shares tumbled about 20% Monday morning after the company disclosed full results from its registrational PATHFINDER 2 study at the American Society of Clinical Oncology annual meeting. The Galleri multi-cancer early detection test was evaluated in 35,878 U.S. and Canadian participants aged 50 and older. The study found a large increase in cancer detection when Galleri was added to recommended screenings, very high specificity, and moderate overall sensitivity, with analysts noting the ASCO update was roughly in line to slightly mixed and flagging potential near-term volatility despite confidence in long-term prospects.

Grail Shares Drop After PATHFINDER 2 Results; Market Reaction Tempered by Mixed Takeaways
GRAL

Key Points

  • Grail stock declined about 20% after full PATHFINDER 2 results were presented at ASCO, reflecting investor reaction to a mixed reception of the data.
  • PATHFINDER 2 evaluated the Galleri multi-cancer early detection test in 35,878 participants aged 50+ in the U.S. and Canada, reporting a 6.5-fold increase in cancer detection when added to recommended screenings and a 99.6% specificity.
  • Analysts expressed differing near-term outlooks: TD Cowen noted potential giveback of recent gains after an in-line to slightly mixed update, while Canaccord Genuity maintained a buy rating and an $80 target, citing confidence in long-term adoption.

Shares of Grail Inc (NASDAQ:GRAL) fell roughly 20% in early trading Monday after the company released full results from its registrational PATHFINDER 2 study at the American Society of Clinical Oncology annual meeting.

The PATHFINDER 2 trial enrolled 35,878 participants aged 50 and over across the U.S. and Canada to evaluate the Galleri multi-cancer early detection test. According to the company, adding Galleri to recommended screenings for breast, colorectal, cervical and lung cancers produced a 6.5-fold increase in cancer detection versus recommended screening alone.

Key performance measures reported from the study included:

  • Episode sensitivity of 39.3% for all cancers captured in the study cohort.
  • Episode sensitivity of 69.8% for the subset of 12 cancers that account for approximately two-thirds of cancer deaths in the U.S.
  • Specificity of 99.6%, corresponding to a false positive rate below 0.4%.
  • Positive predictive value of 60.3%, consistent with the trial's previously published initial results.
  • Identification of Cancer Signal Origin in 91.3% of cases where a cancer signal was detected.
  • Median time to diagnostic resolution of 48 days following detection.

The PATHFINDER 2 dataset, described by the company as registrational, indicates that 71% of new cancers detected by the Galleri test were diagnosed at stages I through III.

Market commentary accompanying the release highlighted how investor sentiment had been elevated heading into ASCO. TD Cowen analyst Dan Brennan noted that the stock had climbed roughly 70% from February lows into the conference, and that some of those gains could be given back given what he characterized as an "in line to slightly mixed" ASCO update.

Canaccord Genuity analyst Kyle Mikson kept a buy rating on the shares with an $80 price target. Mikson said a near-term pullback remains possible but reaffirmed the firm's confidence in longer-term share appreciation, citing what the firm views as strong data generation in multi-cancer early detection and execution toward broader adoption.

On the regulatory and reimbursement front, Grail submitted an FDA premarket approval (PMA) application in the first quarter of 2026 and during the same period legislation was passed that the company said outlines a path to Medicare coverage.

Investors reacted quickly to the ASCO presentation, pricing in the mixed elements of the dataset and prompting notable intraday selling pressure. The study’s high specificity and Cancer Signal Origin performance stand alongside overall sensitivity results that analysts described as mixed, shaping the current market response.


What to watch next

  • Market response in the days following the ASCO presentation and whether selling pressure stabilizes.
  • Progress on the FDA PMA review and any follow-up data or clarifying analyses Grail may provide about PATHFINDER 2 performance metrics.
  • Implementation details related to the legislation outlining a path to Medicare coverage and how that may affect clinical adoption timelines.

Risks

  • Near-term share price volatility - Analysts flagged the possibility of a pullback following what they described as an in-line to slightly mixed ASCO update.
  • Market sentiment risk - Elevated share price into ASCO left room for giving back gains when results were not uniformly positive, contributing to intraday selling pressure.
  • Operational/diagnostic uncertainty - The median diagnostic resolution time reported was 48 days, a metric that may influence clinical workflow and follow-up processes as adoption is considered.

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