Roche Receives CE-IVDR Approval for HER2 Companion Diagnostic Identifying HER2-Ultralow Breast and Biliary Tract Cancer Patients

• The VENTANA HER2 (4B5) test gains CE-IVDR approval for assessing HER2-ultralow status, potentially identifying metastatic breast cancer patients suitable for ENHERTU treatment.
• The VENTANA HER2 (4B5) test is now also approved to identify patients with previously-treated, unresectable or metastatic HER2-positive biliary tract cancer (BTC) who may be eligible for treatment with ZIIHERA.
• Roche strengthens its position in breast cancer diagnostics, expanding patient access to personalized treatment options.

TUCSON, Ariz. – Roche (SIX: RO, ROG; OTCQX: RHHBY) announced today it has secured CE IVDR (In Vitro Diagnostic Regulation) approval for two label expansions of its VENTANA HER2 (4B5) Rabbit Monoclonal Primary Antibody RxDx assay. This development marks a significant step forward in personalized cancer treatment, as HER2, a receptor protein expressed across various cancers, serves as a crucial predictive biomarker for determining a patient’s potential response to HER2-targeted therapies.

The VENTANA HER2 (4B5) test distinguishes itself as the first and only companion diagnostic approved for identifying HR-positive metastatic breast cancer patients exhibiting HER2-ultralow expression. This patient subgroup may now be considered for treatment with ENHERTU (trastuzumab deruxtecan), an antibody-drug conjugate (ADC) engineered specifically to target HER2. ENHERTU was discovered by Daiichi Sankyo and is being jointly developed and commercialized by both Daiichi Sankyo and AstraZeneca. Additionally, the VENTANA HER2 (4B5) assay achieves another first as a companion diagnostic tool in the assessment of HER2-positive status – it is now approved to identify biliary tract cancer (BTC) patients with an immunohistochemistry score of 3+ who may be eligible for treatment with Jazz Pharmaceuticals’ ZIIHERA (zanidatamab-hrii).

“This expansion is about forging new pathways for patients grappling with challenging cancers,” stated Jill German, Head of Pathology Lab at Roche Diagnostics. “Our evolving understanding of HER2 is rapidly shaping diagnostic practices, and this expanded approval ensures that our diagnostic tools lead the way. We’re empowering clinicians to provide personalized and potentially life-altering treatments for patients in urgent need.”

The Evolving Landscape of HER2 Testing in Breast Cancer

Breast cancer remains a significant health challenge in Europe, with projections indicating over 564,000 diagnoses and 145,000 deaths this year alone. The incidence of metastatic breast cancer is showing an increase in younger populations, making it the leading cause of breast cancer-related mortality.

Traditional HER2 interpretation in breast cancer has typically involved binary “positive” or “negative” classifications. Now, this VENTANA HER2 (4B5) test allows for the identification of “HER2-ultralow” patients, denoting those with very low levels of HER2 expression – even lower than the currently defined HER2-low category. Approximately 20-25% of hormone receptor (HR)-positive, HER2-negative breast cancer patients may fall within the HER2-ultralow designation. The significance here is that these patients may be eligible for treatment with ENHERTU, expanding the potential reach of targeted therapies.

The clinical validity of this expanded application is supported by findings from DESTINY-Breast06, a key clinical trial. The study demonstrated that ENHERTU yielded a significant improvement in progression-free survival compared to standard chemotherapy regimens in patients with HER2-low and HER2-ultralow metastatic breast cancer. This data substantially reinforces the value of identifying HER2-ultralow patients.

Addressing Critical Unmet Needs in Biliary Tract Cancer

Biliary tract cancer (BTC) represents a notably challenging oncology space. In Europe, both the incidence of BTC and mortality rates due to this disease have been on the rise in recent decades. Compounding the issue is the tendency for BTC to be diagnosed at an advanced stage, leaving patients with very limited treatment options and, subsequently, a poor prognosis. The VENTANA HER2 (4B5) test’s new approval to identify BTC patients with HER2-positive status who may be eligible for ZIIHERA treatment addresses a critical gap in the current therapeutic landscape.

Deep Dive: The VENTANA HER2 (4B5) Assay – Technology & Utility

The VENTANA HER2 (4B5) Rabbit Monoclonal Primary Antibody RxDx assay is strategically designed to deliver timely and reliable results that drive diagnostic certainty. This heightened diagnostic confidence facilitates informed therapeutic decisions and ultimately contributes to improved patient outcomes. The assay was previously indicated as an aid in identifying certain breast cancer patients eligible for HER2-targeted treatments such as Herceptin, KADCYLA, PERJETA, or ENHERTU, as well as helping identify gastric cancer patients eligible for Herceptin. The assay is used in concert with the fully automated VENTANA BenchMark slide staining instrument which is key to its consistency and reliability.

The system standardizes all immunohistochemistry (IHC) processes, from baking to staining, which reduces the probability of human error. The assay’s standardized approach significantly reduces inconsistencies typically observed with manual or semi-automated IHC methods due to varying reagent dilutions and other manual processes. The HER2 (4B5) clone is notable for consistently achieving high proficiency assessment scores (compared to alternatives) and exhibits strong concordance with HER2 FISH (fluorescence in situ hybridization) results, solidifying its position as a highly reliable HER2 IHC primary antibody.

More details about Roche’s broad diagnostics portfolio are available on the Roche Diagnostics Pathology Lab companion diagnostics page.

About Roche

Founded in 1896 in Basel, Switzerland, Roche emerged as one of the pioneers in the industrial manufacturing of branded medicines. The company has evolved into the world’s largest biotechnology firm and a global leader in in-vitro diagnostics. Roche pursues scientific excellence to discover and develop transformative medicines and diagnostics that improve and save lives worldwide. The company is a pioneering force in personalized healthcare and committed to reshaping healthcare delivery for greater impact. By partnering with diverse stakeholders and integrating its diagnostic and pharmaceutical expertise with data-driven insights from clinical practice, Roche aims to provide the best possible care for each individual.

Sustainability is a core value at Roche. As a science-driven organization, the company’s most significant contribution to society lies in the development of innovative medicines and diagnostics that facilitate healthier lives. Roche is furthering its sustainability commitments through the Science Based Targets initiative and the Sustainable Markets Initiative with ambitious goals for achieving net-zero emissions by 2045.

Genentech, headquartered in the United States, operates as a wholly-owned member of the Roche Group. Roche holds a majority stake in Chugai Pharmaceutical, based in Japan.

For more information, visit Roche’s website at www.roche.com.

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

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

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