Roche receives FDA approval for first diagnostic tests to identify HER2-positive metastatic breast cancer patients eligible for ENHERTU

• FDA expands labels for Roche's PATHWAY HER2 (4B5) test* and VENTANA HER2 Dual ISH DNA Probe Cocktail, which can now be used to identify HER2-positive metastatic breast cancer patients that could be eligible for ENHERTU.
  
  
• Roche's PATHWAY HER2 (4B5) test is the only test approved to identify all levels of HER2 expression.
  
  
• Roche's breast cancer diagnostic portfolio now provides clinicians with a comprehensive solution to assess HER2 expression and guide treatment decisions for this challenging disease.

TUCSON, Ariz., Dec. 15, 2025 /PRNewswire/ -- Roche (SIX: RO, ROG; OTCQX: RHHBY) announced today that the U.S. Food and Drug Administration (FDA) has approved additional indications for its PATHWAY anti-HER2/neu (4B5) Rabbit Monoclonal Primary Antibody and VENTANA HER2 Dual ISH DNA Probe Cocktail tests. These tests are now approved to aid in identifying HER2-positive metastatic breast cancer (mBC) patients who may be eligible for treatment with ENHERTU^® (trastuzumab deruxtecan), a specifically engineered HER2-directed antibody drug conjugate (ADC) discovered by Daiichi Sankyo and being jointly developed and commercialised by Daiichi Sankyo and AstraZeneca.

Until now, Roche's PATHWAY HER2 (4B5) test had been approved for identifying mBC patients with HER2-low and HER2-ultralow expression. With this expanded approval, Roche's PATHWAY HER2 (4B5) test in combination with the VENTANA HER2 Dual ISH DNA Probe Cocktail can now be used to identify patients across the full spectrum of HER2 expression for potential eligibility for ENHERTU. This approval reflects the vital role of advanced diagnostics in guiding precise treatment decisions to address the diverse needs of mBC patients.

"Metastatic breast cancer remains a significant challenge," said Laura Apitz, Head of Pathology Lab at Roche Diagnostics. "Diagnostic advances like these bring much-needed hope for patients. With this approval, our breast diagnostic portfolio can further guide therapy decisions for clinicians, enabling a more personalised approach."

Advancing Science in HER2 Breast Cancer
Breast cancer now represents one in four of all cancers diagnosed in women worldwide.¹ Despite advances in care, metastatic breast cancer poses a growing challenge, especially in younger populations,^2,3 where cases among women aged 25 to 39 increased by 32% between 2009 and 2015.^2,3

However, treatment for metastatic breast cancer is evolving alongside a deeper understanding of HER2 biology, which now shows that HER2 expression exists on a continuous spectrum rather than as distinct "positive" or "negative" categories.⁴

These diagnostics strengthen Roche's broader breast cancer portfolio, which offers solutions that cover the full spectrum of breast cancer management, including important predictive assays. Roche remains committed to supporting patients with advanced diagnostic tools that help clinicians improve outcomes and deliver more personalized care at every stage of the disease.

About PATHWAY anti-HER2/neu (4B5) Rabbit Monoclonal Primary Antibody
The PATHWAY anti-HER2/neu (4B5) Rabbit Monoclonal Primary Antibody delivers timely, clear and reliable results, driving diagnostic certainty and enabling therapeutic decisions that can lead to better outcomes for patients. Previously indicated as an aid to identify certain breast cancer patients eligible for HER2-targeted treatment with Herceptin^®, KADCYLA^®, or ENHERTU,⁵ the test is used in combination with the fully automated BenchMark ULTRA and BenchMark ULTRA PLUS staining platforms.

The assay standardizes all IHC processes from baking through staining, and reduces the possibility of human error.⁵ It also minimizes inherent variability resulting from individual reagent dilution and other processes found in manual and semi-automated IHC methods. The HER2 (4B5) clone achieves consistently high proficiency assessment scores compared to other clones⁶ and demonstrates high concordance with HER2 FISH,^7.8 empowering laboratories to employ the most widely adopted and reliable HER2 IHC primary antibody.

About the VENTANA HER2 Dual ISH DNA Probe Cocktail assay
The VENTANA HER2 Dual ISH DNA Probe Cocktail assay is a fully automated, ready-to-use brightfield solution for determining HER2 gene status. VENTANA HER2 Dual ISH helps identify breast cancer patients eligible for personalized treatment with HER2-targeted therapies. The VENTANA HER2 Dual ISH DNA Probe Cocktail assay is optimised for use with the VENTANA Silver ISH DNP Detection Kit and the VENTANA Red ISH DIG Detection Kit on the fully-automated BenchMark ULTRA and BenchMark ULTRA PLUS staining platforms.⁹

The VENTANA HER2 Dual ISH DNA Probe Cocktail assay is an enhanced version of the previous-generation test. New oligonucleotide probes and highly sensitive detection kits provide clear results to pathology labs more quickly, allowing clinicians to make treatment decisions earlier.

For more information, please visit the Roche Diagnostics Pathology Lab companion diagnostics page.

About Roche
Founded in 1896 in Basel, Switzerland, as one of the first industrial manufacturers of branded medicines, Roche has grown into the world's largest biotechnology company and the global leader in in-vitro diagnostics. The company pursues scientific excellence to discover and develop medicines and diagnostics for improving and saving the lives of people around the world. We are a pioneer in personalised healthcare and want to further transform how healthcare is delivered to have an even greater impact. To provide the best care for each person we partner with many stakeholders and combine our strengths in Diagnostics and Pharma with data insights from the clinical practice.

For over 125 years, sustainability has been an integral part of Roche's business. As a science-driven company, our greatest contribution to society is developing innovative medicines and diagnostics that help people live healthier lives. Roche is committed to the Science Based Targets initiative and the Sustainable Markets Initiative to achieve net zero by 2045.

Genentech, in the United States, is a wholly owned member of the Roche Group. Roche is the majority shareholder in Chugai Pharmaceutical, Japan.

For more information, please visit www.roche.com.

* Hereafter referred to as PATHWAY HER2 (4B5) test

All trademarks used or mentioned in this release are protected by law.

References
[1] Breast Cancer Resource Foundation [Internet; cited 21 Nov 2024] Available from: https://www.bcrf.org/breast-cancer-statistics-and-resources/
[2] Breast Cancer Resource Foundation [Internet; cited 2024 Oct 8] Available from: https://www.bcrf.org/blog/metastatic-breast-cancer-symptoms-treatment/#:~:text=In%20the%20U.S.%20today%2C%20there,cancer%20diagnoses%20in%20young%20women.
[3] Hendrick RE, Helvie MA, Monticciolo DL. Breast Cancer Mortality Rates Have Stopped Declining in U.S. Women Younger than 40 Years. Radiology. 2021 Apr;299(1):143-149.
[4] Morrar D, Brogi E, Schwartz CJ, Pareja F, Wen HY, Ross DS, HER2-ultralow Breast Cancer: Incidence, Clinicopathologic Features and Need for Refined Scoring System, Modern Pathology (2025), doi: https://doi.org/10.1016/j.modpat.2025.10091 [5] Roche. PATHWAY anti-HER2/neu (4B5) Rabbit Monoclonal Primary Antibody, US Package Insert (D218295 Rev 2). 2025.
[6] NordiQC Assessments. https://www.nordiqc.org/epitope.php?id=11. Accessed January 28, 2025.
[7] Mayr D, et al. Comprehensive immunohistochemical analysis of Her-2/neu oncoprotein overexpression in breast cancer: HercepTest^™ (Dako) for manual testing and Her2/neuTest 4B5 (VENTANA) for VENTANA BenchMark automatic staining system with correlation to results of BenchMark automatic staining system with correlation to results of fluorescence in situ hybridization (FISH). Virchows Archiv. 2009; 454(3):241–248.
[8] Brügmann A, Lelkaitis G, Nielsen S, et al. Testing HER2 in breast cancer: a comparative study on BRISH, FISH, and IHC. Appl Immunohistochem Mol Morphol. 2011;19(3):203-211.
[9] Roche. VENTANA HER2 Dual ISH DNA Probe Cocktail, US Package Insert (D218296 Rev 1). 2025.

Roche Media Relations
Jo Lynn Garing
Phone: +1 317-363-7286
Email: [email protected]

SOURCE Roche