NanoString Technologies to present clinical study of Prosigna Breast Cancer Assay at ASCO 2013

NanoString Technologies, Inc., a privately held provider of life science tools for translational research and molecular diagnostic products, today announced that a clinical study of the Prosigna Breast Cancer Assay will be presented during the Breast Cancer Oral Abstract Session at the 2013 Annual American Society of Clinical Oncology (ASCO) Meeting on Sunday, June 2. Results of the study are based on an analysis of the combined data set of the Austrian Breast & Colorectal Cancer Study Group 8 (ABCSG-8) and Arimidex, Tamoxifen, Alone or in Combination (ATAC) studies.

“These data confirm that the Prosigna Gene Signature Assay can offer clinically relevant and actionable information, such as the ROR score, which may help guide future breast cancer treatment decisions”

The Prosigna Breast Cancer Assay, which is based on the PAM50 gene signature, has been previously validated in two clinical studies using samples from patients enrolled in the ABCSG-8 and ATAC trials. The new study is based on the analysis of the combined data set and long term follow-up from 2,485 patients in these studies, including 1,478 patients from the ABCSG-8 trial and 1,007 patients from the ATAC trial. Patients in the combined data set were grouped into one of three categories based on the number of positive nodes: 1 node (N1), 2 nodes (N2), and 2 or 3 nodes (N2-3).

Results of the analysis demonstrate that the outputs of the Prosigna Breast Cancer Assay, including the Risk of Recurrence (ROR) score, ROR-based risk group, and intrinsic subtype all added statistically significant prognostic information to that provided by the clinical and pathological variables in all groups. The ROR score allowed the identification of a low-risk group of patients, which accounted for 40 percent of N1 patients who experienced an absolute 10-year risk of distant recurrence rate of 6.6 percent. The investigators also concluded that the Prosigna Assay reliably generated additional prognostic information to that provided by the clinical and pathological variables, and may be useful in identifying postmenopausal women with node-positive, hormone-receptor positive (HR+) early-stage breast cancer that can be spared adjuvant chemotherapy.

"These data confirm that the Prosigna Gene Signature Assay can offer clinically relevant and actionable information, such as the ROR score, which may help guide future breast cancer treatment decisions," said Brad Gray, President and Chief Executive Officer of NanoString Technologies. "As we continue to expand the global footprint for Prosigna, this analysis further solidifies the value of this assay for informing treatment decisions in early-stage breast cancer."

SOURCE NanoString Technologies, Inc.