Roche's test wins FDA approval to identify certain breast cancer patients eligible for Enhertu
trabantos/iStock via Getty Images

The U.S. Food and Drug Administration (FDA) approved Roche's (OTCQX:RHHBY) (OTCQX:RHHBF) PATHWAY anti-HER2/neu (4B5) Rabbit Monoclonal Primary Antibody test to identify patients with metastatic breast cancer with low HER2 expression for whom Enhertu can be used as a targeted treatment.
The test is the only FDA approved companion diagnostic indicated to assess HER2 low status in patients with metastatic breast cancer, the company said in an Oct. 4 press release.
The Swiss pharma giant added that the FDA approval of the new HER2 low indication expands on the intended use of its on-market PATHWAY anti-HER2 (4B5) test.
The test was used as part of a study called DESTINY-Breast04 by AstraZeneca (AZN) and Daiichi Sankyo (OTCPK:DSKYF) (OTCPK:DSNKY), the developers of Enhertu (fam-trastuzumab deruxtecan-nxki), to identify patients whose tumors expressed low levels of HER2 protein, Roche added.
A companion diagnostic is a test that helps determine if a particular therapy's benefit to patients will outweigh any potential serious side effects or risks, and also helps identify patients who are more likely to benefit from a particular drug, according to the FDA.
In August, the FDA approved Guardant Health's (GH) liquid biopsy test Guardant360 CDx as a companion diagnostic to to identify patients with a type lung cancer who could be treated with Enhertu.