Genetic Test Approved for Metastatic Lung Cancer

The qualitative test is used to detect rearrangements involving the ALK gene via fluorescence in situ hybridization (FISH) in formalin-fixed, paraffin-embedded (FFPE) non-small-cell lung cancer (NSCLC) tissue specimens.

The Vysis Paraffin Pretreatment IV and Post Hybridization Wash Buffer Kit used to prepare paraffin-embedded lung cancer tissue sections fixed on positively charged slides for use in FISH with Vysis DNA FISH probes. The DNA contained within the nuclei of the FFPE tissue sections is denatured to the single-stranded form and subsequently allowed to hybridize with the locus-specific indicator Vysis ALK Break Apart FISH Probes. Hybridization of the Vysis ALK Break Apart FISH Probes is viewed using a fluorescence microscope equipped with appropriate excitation and emission filters, allowing visualization of the orange and green fluorescent signals.

A total of 255 patients with late-stage ALK-positive NSCL were enrolled in two multicenter single arm studies. A sample of a patient’s lung cancer tissue was collected and tested for the ALK gene abnormality prior to study enrollment. The studies were designed to measure objective response rate, the percentage of patients who experienced complete or partial cancer shrinkage. Most patients in the studies had received prior chemotherapy. In one study, the objective response rate was 50% with median response duration of 42 weeks. In another, the objective response rate was 61% with median response duration of 48 weeks. The ALK gene abnormality causes cancer development and growth. About 1% to 7% of those with NSCLC have the ALK gene abnormality. Patients with this form of lung cancer are typically nonsmokers.

The US Food and Drug Administration (FDA; Silver Springs, MD, USA) based its approval of the Vysis ALK Break Apart FISH Probe Kit (Abbott Molecular Inc, Des Plaines, IL, USA) on data from one of the studies. Alberto Gutierrez, PhD, a director at the FDA, said, "The trend in oncology research continues towards targeted therapies. This test is an example of the important role companion diagnostics play in determining that the safest and most effective treatments are promptly delivered to patients living with serious and life-threatening diseases.”

Related Links:
US Food and Drug Administration
Abbott Molecular Inc.