Response Genetics announced this week that it has expanded its ResponseDX: Lung genetic test panel to detect the presence of EML4-ALK gene variants in lung cancer patients.
Approximately 4 percent of non-small cell lung cancer patients harbor EML4-ALK fusion gene rearrangements, which have been shown in clinical trials to promote tumor cell growth and hinder response to EGFR-inhibiting treatments.
Pfizer is currently developing the drug crizotinib, a non-small cell lung cancer drug for patients carrying the EML4-ALK fusion oncogene. At the American Society of Clinical Oncology's annual meeting, the company presented interim data from a Phase I/II study that supported the hypothesis that molecularly stratifying patients ahead of treatment with crizotinib improves patient outcomes (PGx Reporter 06/09/10).
The researchers reported at the time that out of 50 patients for whom responses were evaluable, the overall response rate was 64 percent and the disease control rate was 90 percent. The early study results were presented during a plenary session and were considered to be one of the highlights at ASCO's annual meeting.
Abbott Molecular developed the FISH test that Pfizer used to stratify patients in clinical trials. However, researchers involved in the study noted that immunohistochemistry tests could also provide comparable results in stratifying patients.
According to a statement from Response Genetics, its PCR-based lung cancer test detects nine known fusion gene variants. "This new test is expected to be useful for large-scale screening of tissue samples and is available nationwide through the company's sales force," the company said. The test analyzes formalin fixed paraffin embedded tissue samples.
Kathleen Danenberg, Response Genetics CEO, said in a statement that the oncology community has "rapidly accepted" its EML4-ALK test. In addition to EML4-ALK rearrangements, ResponseDX: Lung also gauges the expression of genes in excision repair cross-complementing factor 1, thymidylate synthase, EGFR, ribonucleotide reductase M1, and HER2; the test also detects KRAS and EGFR gene mutations.
The turnaround time for Response Genetics' test is five to seven days from receipt of the sample. The test uses standard CPT codes for Medicare reimbursement.
"Response Genetics is committed to expanding its existing ResponseDX tests as genes that correlate with therapeutic benefit are identified," said Danenberg. "With the addition of EML4-ALK, our ResponseDX: Lung genetic panel gives physicians even more information to help this unique group of patients with treatment-resistant lung cancer."