Angle PLC's HER2 Assay: A Game Changer for Breast Cancer Treatment

Angle PLC, a world-leading liquid biopsy company, recently announced the presentation of an independent study at the San Antonio Breast Cancer Symposium (SABCS) from December 10 to 13, 2024. The study, conducted by Weill Cornell Medicine, supports ANGLE's HER2 assay development program and demonstrates the potential for stratifying breast cancer patients for treatment with HER2 antibody drug conjugates (ADCs). The findings corroborate ANGLE's own findings and provide a semi-automated Parsortix®-based HER2 workflow, which could enable more accurate and efficient patient selection for clinical trials and treatment with HER2-targeted therapies. This development is significant as it addresses the challenge of identifying patients who may benefit from HER2-targeted therapies, particularly those who were initially HER2-negative but have since become HER2-low or positive. By leveraging ANGLE's innovative CTC solutions, this approach could enhance the precision and effectiveness of breast cancer treatment.

The Parsortix®-based HER2 workflow offers a significant advancement in breast cancer treatment by enabling longitudinal, repeat assessment of HER2 status in patients. This is achieved through the isolation of circulating tumor cells (CTCs) from peripheral blood using the Parsortix® system, followed by quantification of HER2 gene amplification via fluorescence in situ hybridization (FISH) and HER2 protein expression via immunofluorescence (IF) staining. The workflow's high analytical sensitivity and specificity, as demonstrated in studies using epithelial, mesenchymal, and blood lineage markers, allow for accurate identification and quantification of HER2-positive CTCs. This approach has the potential to identify patients who were previously HER2-negative but have since become HER2-low or positive, enabling them to benefit from treatment with HER2-targeted antibody drug conjugates (ADCs) or anti-HER2 therapy. Furthermore, the workflow's ability to detect ranges of HER2 expression can help identify patients suitable for newer HER2-targeted ADCs. By providing an optimized, easily implemented solution for longitudinal HER2 assessment, the Parsortix®-based HER2 workflow contributes to the advancement of breast cancer treatment, offering improved patient stratification and personalized therapy.


The Parsortix®-based HER2 workflow has shown promising results in clinical studies. In a cohort of 43 metastatic breast cancer (MBC) patients, the workflow identified cases where HER2 status had changed over time. Approximately 80% of breast cancer patients are initially categorized as HER2 negative, but HER2 status can change, and a blood-based test can help identify patients who may now benefit from treatment with HER2-targeted therapies. By enabling longitudinal, repeat assessment of HER2 CTC status, the assay can help identify patients whose HER2 status has changed, potentially expanding the pool of patients eligible for HER2-targeted therapies. This could lead to improved patient outcomes by providing more personalized and effective treatment options.


In conclusion, Angle PLC's HER2 assay, presented at the SABCS, offers a significant advancement in breast cancer treatment. By enabling longitudinal, repeat assessment of HER2 status in patients, the Parsortix®-based HER2 workflow can help identify patients who were previously HER2-negative but have since become HER2-low or positive. This approach can improve patient stratification and personalized therapy, ultimately leading to better patient outcomes. As the workflow continues to demonstrate its potential in clinical studies, it is poised to become an essential tool in the fight against breast cancer.