Roche's Expansion in Companion Diagnostics: A Strategic Catalyst for Long-Term Growth

Roche’s recent CE IVDR approval for the VENTANA HER2 (4B5) test marks a pivotal advancement in personalized oncology, expanding access to targeted therapies for previously underserved patient populations. This diagnostic tool, now approved in Europe, enables the identification of HER2-ultralow metastatic breast cancer patients eligible for ENHERTU (trastuzumab deruxtecan) and HER2-positive biliary tract cancer (BTC) patients who may benefit from ZIIHERA (zanidatamab-hrii) [1]. By defining a new “HER2-ultralow” category—patients with HER2 expression levels even lower than the existing HER2-low classification—Roche has effectively broadened the scope of HER2-targeted therapies, unlocking a market estimated to include 20–25% of HR-positive, HER2-negative breast cancer patients [2].

Expanding Therapeutic Markets with Precision Diagnostics

The approval of the VENTANA HER2 (4B5) test is underpinned by robust clinical evidence. In the DESTINY-Breast06 trial, ENHERTU demonstrated a statistically significant improvement in progression-free survival compared to standard chemotherapy for patients with HER2-low and HER2-ultralow metastatic breast cancer [1]. This trial not only validated the test’s utility but also underscored the growing importance of precision diagnostics in oncology. For BTC—a rare and aggressive cancer with limited treatment options—the test now provides a companion diagnostic to identify patients who could benefit from ZIIHERA, a bispecific antibody targeting HER2 [3].

Market dynamics further amplify the strategic value of this expansion. The HER2-positive breast cancer treatment market was valued at USD 10.96 billion in 2025 and is projected to reach USD 14.41 billion by 2029, driven by the adoption of antibody-drug conjugates (ADCs) like ENHERTU [4]. Meanwhile, the fluorescent in situ hybridization (FISH) market, which includes companion diagnostics, is expected to grow at a 7.33% CAGR, reaching USD 1.69 billion by 2030 [5]. Roche’s automated and standardized immunohistochemistry (IHC) processes, as highlighted in its diagnostic solutions, reduce human error and variability, positioning the VENTANA HER2 (4B5) test as a reliable tool for laboratories [1].

Strengthening Diagnostic Leadership and Competitive Positioning

Roche’s leadership in HER2 diagnostics is reinforced by its comprehensive portfolio, including the VENTANA HER2 Dual ISH DNA Probe Cocktail Assay and its role in developing next-generation therapies. The company’s recent acquisition of Zion Pharma to advance a blood-brain-barrier-penetrant HER2 inhibitor for brain metastases exemplifies its commitment to addressing unmet needs in oncology [4]. Additionally, Roche’s acquisition of Poseida Therapeutics to bolster its cell therapy pipeline underscores its long-term vision for personalized medicine [6].

However, the market is not without challenges. Biosimilars are eroding the market share of traditional HER2-targeted therapies like Herceptin, which is projected to decline at a -5.62% CAGR from 2025 to 2032 [4]. Roche’s response lies in its ADCs and subcutaneous fixed-dose combinations, which improve patient adherence and outcomes. The VENTANA HER2 (4B5) test, by enabling precise patient stratification, complements these therapies and mitigates the impact of biosimilars through value-based differentiation [4].

Future Outlook and Strategic Implications

Looking ahead, Roche’s expansion into HER2-ultralow and BTC diagnostics aligns with broader trends in precision oncology. The Asia-Pacific region, in particular, presents significant growth opportunities due to rising cancer incidence and healthcare investments [4]. Furthermore, advancements in technologies like liquid biopsies and HER2-specific CAR-T cell therapies—shown to inhibit solid tumors—could further expand the addressable market for Roche’s diagnostics [7].

Conclusion

Roche’s CE IVDR approval for the VENTANA HER2 (4B5) test is more than a regulatory milestone—it is a strategic catalyst for long-term growth. By expanding access to targeted therapies for HER2-ultralow and BTC patients, Roche solidifies its leadership in personalized oncology while navigating competitive pressures through innovation. As the market for precision diagnostics and ADCs accelerates, Roche’s integrated approach to diagnostics and therapeutics positions it as a key player in shaping the future of cancer care.

**Source:[1] Roche receives CE IVDR approval for HER2 (4B5) companion diagnostic test to identify HER2-ultralow breast cancer and biliary tract cancer patients [https://diagnostics.roche.com/global/en/news-listing/2025/roche-receives-ce-ivdr-approval-for-her2--4b5--companion-diagnos.html][2] Roche Secures CE-IVDR Approval For Expanded [https://www.nasdaq.com/articles/roche-secures-ce-ivdr-approval-expanded-ventana-her2-4b5-diagnostic-applications][3] Ventana Assay Earns CE IVDR Approval in EU as Companion Diagnostic in HER2-Expressing Breast and Biliary Tract Cancers [https://www.onclive.com/view/ventana-assay-earns-ce-ivdr-approval-in-eu-as-companion-diagnostic-in-her2-expressing-breast-and-biliary-tract-cancers][4] HER2-positive Breast Cancer Treatment Market Size & ... [https://www.mordorintelligence.com/industry-reports/her2-positive-breast-cancer-treatment-market][5] Fluorescent In Situ Hybridization Market Size and Share [https://www.mordorintelligence.com/industry-reports/fluorescent-in-situ-hybridization-market][6] fourth quarter marks third straight quarter of 9% growth [https://www.roche.com/media/releases/med-cor-2025-01-30][7] Research progress on HER2-specific chimeric antigen [https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2025.1514994/full]