Roche(US:RHHBY) Prnewswire·2025-09-05 05:00Core Viewpoint - Roche has received CE IVDR approval for two label expansions of its VENTANA® HER2 (4B5) Rabbit Monoclonal Primary Antibody RxDx assay, enhancing diagnostic capabilities for HER2-targeted therapies in breast and biliary tract cancers [1][6]. Summary by Relevant Sections HER2 Testing in Breast Cancer - The VENTANA HER2 (4B5) test is the first companion diagnostic approved for identifying HR-positive metastatic breast cancer patients classified as HER2-ultralow, who may be eligible for treatment with ENHERTU® [2]. - Approximately 20-25% of HR-positive, HER2-negative breast cancer patients may fall into the HER2-ultralow category, which is a new classification beyond traditional HER2-positive or negative [3][4]. - The test was utilized in the DESTINY-Breast06 trial, showing significant improvement in progression-free survival for patients with HER2-low and HER2-ultralow metastatic breast cancer when treated with ENHERTU compared to standard chemotherapy [4][6]. Biliary Tract Cancer Diagnostics - The VENTANA HER2 (4B5) test is now also approved to identify biliary tract cancer patients with HER2-positive status, who may be eligible for treatment with Jazz Pharmaceuticals' ZIIHERA® [2][4]. - The incidence and mortality rates of biliary tract cancer have been increasing, with patients often diagnosed at advanced stages and having limited treatment options [4]. Roche's Commitment to Diagnostics - Roche emphasizes the importance of advancing diagnostics to provide personalized treatment options for patients facing challenging cancers, ensuring that clinicians can offer life-altering therapies [3][6]. - The VENTANA HER2 (4B5) assay standardizes immunohistochemistry processes, reducing human error and variability, thus enhancing diagnostic reliability [7].