China's FDA approves PCR KRAS Assay For Colorectal Cancer

China's State Food and Drug Administration has approved China Medical technologies real-time PCR-based V-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog (KRAS) assay as a companion diagnostic test for the use of a targeted drug for the treatment of Colorectal Cancer patients. The PCR KRAS Assay is a diagnostic test used to detect specific mutations in the KRAS gene using a real-time PCR analyzer and predicts which Colorectal Cancer patients are likely to respond to and benefit from the targeted drug. About 60% of colorectal cancer patients have a non-mutated KRAS gene, while the remaining patients with mutations may not be responsive. For example, a number of large studies have shown that Erbitux has significant efficacy in metastatic Colorectal Cancer patients with KRAS wild-type tumors. In the Phase III CRYSTAL study, published in 2009, patients with the wild-type KRAS gene treated with Erbitux plus chemotherapy showed a response rate of up to 59% compared to those treated with chemotherapy alone.