FDA Advisory Panel Votes to Approve GRAIL Galleri MCED Screening Test

The Molecular and Clinical Genetics Devices Panel of the Medical Devices Advisory Committee of the U.S. Food and Drug Administration (FDA) has voted in favor of the Premarket Approval (PMA) application for GRAIL’s Galleri multi-cancer early detection (MCED) test. In three separate votes conducted on September 23, 2026, the 10 voting members of the committee evaluated the safety, clinical effectiveness, and overall benefit-risk profile of the Galleri test for early cancer screening in adults aged 50 years and older.

The committee voted 7 to 2, with 1 abstention, that the clinical benefits of the Galleri test outweigh its potential risks.

The advisory panel voted unanimously in support of the test’s safety profile. The panel voted 6 to 4 in favor of Galleri’s clinical effectiveness. This vote marks the first advisory committee review of a PMA submission for a multi-cancer early detection test. Although the FDA is not bound by the advisory committee’s vote, the regulatory agency takes panel recommendations into consideration during its final approval determination.

Targeted Methylation Platform and Clinical Design

Developed by GRAIL, Inc., Galleri is an investigational MCED test designed to detect cancer-specific cell-free DNA methylation patterns shared across multiple cancer types prior to the onset of clinical symptoms. The assay utilizes next-generation sequencing, population-scale data, and machine learning algorithms to identify targeted methylation signals associated with aggressive malignancies, including cancers that currently lack standard guideline-recommended screening options.

When a positive cancer signal is identified, the test predicts the cancer signal origin (CSO) to assist clinicians in directing subsequent diagnostic evaluations. According to clinical protocol parameters, Galleri is intended to be used in addition to, and not as a replacement for, standard organ-specific cancer screening modalities such as mammography, colonoscopy, cervical cytology, and low-dose computed tomography.

Key Clinical Takeaways for Oncology Nurses: Screening and Scope

• Adjunctive Screening Purpose: Galleri is designed to complement existing national cancer screening guidelines for adults aged 50 and older, rather than replacing routine screening examinations.
• Broad Malignancy Identification: The targeted methylation platform detects shared cancer signals across multiple lethal tumor types, expanding early detection capability to cancers without established screening tools.
• Diagnostic Origin Guidance: When a cancer signal is detected, the assay provides a predicted cancer signal origin with high accuracy to guide targeted diagnostic workups.
• Intended Patient Population: Clinical application focuses on asymptomatic adults aged 50 years and older who face an elevated risk of cancer development.

Clinical Trial Evidence and Diagnostic Performance

GRAIL’s PMA application is supported by clinical trial data from large-scale interventional and randomized controlled prospective studies conducted under FDA-approved Investigational Device Exemption (IDE) applications.

Across clinical studies, Galleri detected approximately 4 to 7 times more cancers than standard-of-care screening alone. The majority of Galleri-detected malignancies were identified at earlier stages, when treatment with curative intent remains clinically viable. The test maintained a low false-positive rate alongside high accuracy in predicting the primary tissue origin of detected cancer signals.

During the advisory panel proceedings, over 200 physicians, nurses, professional societies, patients, and patient advocates submitted written statements or oral testimony in support of test approval.

Key Clinical Takeaways for Oncology Nurses: Practice and Nursing Care

• Impact on Survival Outcomes: Detecting asymptomatic malignancies more frequently than standard screening supports earlier therapeutic intervention when curative intent is possible.
• Patient Education on Negative Results: Oncology nurses must counsel patients that a "No Cancer Signal Detected" result does not rule out cancer and that adherence to guideline-recommended screening remains mandatory.
• Navigating Positive Test Signals: A "Cancer Signal Detected" result requires prompt secondary diagnostic evaluation guided by the predicted cancer signal origin rather than immediate treatment initiation.
• Low False-Positive Profile: Clinical trial evidence confirms a low false-positive rate, helping minimize patient anxiety and unnecessary invasive procedures.

Regulatory History and Next Steps

The FDA granted Breakthrough Device designation to Galleri in 2018. GRAIL officially submitted its PMA application for the test on January 29, 2026. A final regulatory decision from the FDA regarding the PMA application is anticipated in the coming months.

Reference

1. GRAIL, Inc. FDA Advisory Committee votes in favor of approval of GRAIL's Galleri® multi-cancer early detection test. Press release. PR Newswire. Published September 23, 2026. Accessed September 24, 2026. https://www.prnewswire.com/news-releases/fda-advisory-committee-votes-in-favor-of-approval-of-grails-galleri-multi-cancer-early-detection-test-302888303.html