(RxWiki News) The anti-cancer drug erlotinib (Tarceva) may slow or stop cancer depending on the type and extent of the disease. A blood test can help patients find out how they will respond to the drug.
VeriStrat is a simple blood test that helps guide therapy for patients with advanced non-small cell lung cancer (NSCLC).
A recent study found the test can foretell how a patient will respond to erlotinib, but cannot predict overall survival.
"Research which tests work for cancer therapy."
David Carbone, MD, professor of Medicine, Cell Biology, and Cancer Biology at the Vanderbilt University Medical Center, and director of the Thoracic Oncology Center at the Vanderbilt-Ingram Cancer Center in Nashville, Tenn., and colleagues analyzed data on 441 plasma samples from patients who were being treated for advanced non-small cell lung cancer.
Erlotinib has been shown to work best on mutations of a protein that is found in high levels on the surface of certain cancer cells.
The protein is called epidermal growth factor receptor (EGFR). EGFR activates an enzyme that leads cells to grow and multiply.
For advanced NSCLC, data from the VeriStrat test can help clinicians make a more informed decision about whether or not erlotinib is the best option for treatment.
For this study, researchers used the Veristrat test, and put patients in groups labeled “Good” or “Poor.”
The ‘Good’ patients lived 10.5 months on erlotinib compared with 6.6 months on placebo. Poor patients on erlotinib had a median survival of 4 months, while those on placebo lived about 3 months.
Investigators said VeriStrat is able to predict response, but not overall survival to the drug.
“The test was able to successfully predict which patients were more likely to have tumor shrinkage,” said Lesley Seymour, MD and PhD, a professor of oncology at Queens University, Kingston, Ontario, and codirector of the Investigational New Drug Program at the National Cancer Institute of Canada (NCIC). She led the original trials for this study.
“The results did not translate into being able to select patients who would live longer,” Dr. Seymour told dailyRx News.
“The ‘Good’ patients did have a longer survival from ‘Poor’ patients, but both groups had some benefit from erlotinib. If we included a thousand patients instead of a few hundred it may have shown a statistical predictive effect as far as survival is concerned.”
The study authors concluded, “Further studies are required to define the clinical utility of VeriStrat and other blood-based biomarkers in defining the appropriate patient population for therapy with erlotinib and other EGFR-based therapies,”
The study was published in the November issue of the Journal of Thoracic Oncology from the International Association for the Study of Lung Cancer. No conflicts of interest were reported.