This is a brief overview of information related to FDA’s approval to market this product. See the links below to the Summary of Safety and Effectiveness Data (SSED) and product labeling for more complete information on this product, its indications for use, and the basis for FDA’s approval.

Product Name: PATHWAY anti-HER2 (4B5) Antibody
PMA Applicant: Ventana Medical Systems, Inc.
Address: 1910 East Innovation Park Drive, Tucson, AZ 85755 
Approval Date: September 30, 2022
Approval Order Statement: Approval Order

What is it?

The PATHWAY anti-HER2 (4B5) Antibody assay is a laboratory test designed to detect HER2 protein in patients with breast cancer. If the test shows that a patient’s breast cancer does have HER2 protein, the patient may benefit from specific FDA-approved treatments including HERCEPTIN and KADCYLA.

This approval expands the indications for this test to include HER2 protein testing for patients with breast cancer who may benefit from treatment with ENHERTU.

How does it work?

The doctor takes a small sample of tumor tissue from the patient and sends it to a laboratory for testing. The laboratory treats the small slice of the tissue with the chemical substances called reagents that are part of the PATHWAY anti-HER2 (4B5) Antibody assay. The chemicals react to the HER2 protein in the patient’s sample. If the sample has HER2 protein, it stains brown. If the sample does not have HER2 protein, it will not have any staining. A medical professional reviews the results and sends a report to the patient’s doctor. The doctor uses this information to help manage the care of patients with breast cancer.

When is it used?

The PATHWAY anti-HER2 (4B5) Antibody assay is used to test patients with breast cancer for the HER2 protein.

What will it accomplish?

Test results from the PATHWAY anti-HER2 (4B5) Assay are used to help doctors decide if patients with breast cancer can receive treatment with HERCEPTIN, KADCYLA, or ENHERTU, based on the level of HER2 protein present.

When should it not be used?

There are no known reasons not to use this test.

Additional information (including warnings, precautions, and adverse events):

• Summary of Safety and Effectiveness Data
• Labeling
• Labeling Part 2
• PMA Database Entry