NEW YORK – Roche announced on Wednesday that its companion diagnostic test to determine which breast cancer patients may be eligible for treatment with Daiichi Sankyo's Enhertu (trastuzumab deruxtecan) has received CE marking.
The Ventana HER2 (4B5) Rabbit Monoclonal Primary Antibody RxDx, marketed as Pathway in the US, is intended to identify metastatic breast cancer patients with low HER2 expression for whom Enhertu may be considered as a targeted treatment, Roche said in a statement.
The test now includes a scoring algorithm that can help pathologists identify low expressors of HER2. The lower cutoff allows the assay to identify patients who may benefit from Enhertu, Roche said, adding the pre-diluted assay is intended for use with the BenchMark IHC/ISH slide staining instrument and standardizes all immunohistochemistry processes.
Enhertu is a specifically engineered HER2-directed antibody drug conjugate and is being jointly developed and commercialized by Daiichi Sankyo and AstraZeneca.
The CE mark for the HER2-low indication expands the intended use for the Ventana HER2 assay, which received US Food and Drug Administration approval in 2022.