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: HER2 CISH pharmDx™ Kit
PMA Applicant: Dako Denmark A/S
Address: Dako Denmark A/S, Produktionsvej 42, DK-2600 Glostrup, Denmark
Approval Date: November 30, 2011
Approval Letter: http://www.accessdata.fda.gov/cdrh_docs/pdf10/p100024a.pdf
What is it? The HER2 CISH pharmDx Kit is a laboratory test that uses DNA probes with chromogenic dyes attached to count how many copies of the HER2 gene, located on chromosome 17, are present in a cancer tissue sample. This test which uses a chromogenic in situ (ISH) method is used in breast cancer patients. This test is used by a doctor (pathologist) trained to identify diseases by studying slices of cells and tissues placed on microscope slides to analyze breast cancer tissue samples. If the test result indicates that too many copies of the HER2 gene (gene amplification) are present in the cancer cell, then a breast cancer patient may be eligible for treatment with the cancer drug Herceptin® (Trastuzumab).
How does it work?
- The doctor takes a small tissue sample from the patient’s breast cancer and examines it (biopsy).
- The tissue is embedded in a block of paraffin wax and a thin slice is cut from the block and attached to a glass slide.
- Following the heating and chemical pre-treatment steps, this kit employs a specific red-labeled DNA probe which is designed to uniquely identify and bind to the HER2 gene on chromosome 17. Another blue-labeled probe targets a different region (centromeric) of chromosome 17. The specific hybridization to the two targets results in formation of a distinct red fluorescent signal at each HER2 gene locus and a distinct blue fluorescent signal at each chromosome 17 centromere.
- The two modified DNA probes bound to the nuclei in the tumor biopsy mark the candidate cells.
- The labeled sample is placed under the microscope and examined by a medical professional who checks the quality of the chromogenic signals and records the results. The ratio of red to blue signals shows if there are too many copies of HER2 in the tumor sample.
- The results are reviewed by a pathologist who is trained to read the slides uses a microscope to check the quality, interprets the staining pattern, and reports the results to the ordering doctor.
- The presence of HER2 /neu amplification indicates a patient is eligible for cancer treatment with Herceptin®/Trastuzumab.
When is it used? For breast cancer patients whose tumor characteristics suggest that they might be candidates for Herceptin® therapy.
What will it accomplish? The Dako HER2 CISH pharmDx Kit when used with other clinical information and laboratory tests, helps to determine if a patient with breast cancer is eligible for Herceptin® treatment which may prolong their life.
When should it not be used? When breast cancer patients’ tumor characteristics suggest that they are not candidates for Herceptin® therapy.
Additional information : Summary of Safety and Effectiveness and labeling are available online.