NANOSTRING TECHNOLOGIES, INC. PROSIGNA-001 Prosigna Breast Cancer Prognostic Gene Signature Assay

Used together, the Prosigna Breast Cancer Prognostic Gene Signature Assay and nCounter Dx Analysis System are a nucleic acid hybridization, visualization and image analysis system based upon coded probes designed to detect the messenger RNA transcribed from 58 genes. The test input is purified RNA from FFPE breast tumor specimens which are acquired from surgical resection. The Prosigna assay uses gene-specific probe pairs that hybridize directly to the mRNA transcripts in solution. The nCounter Dx Analysis System delivers direct, multiplexed measurements of gene expression through digital readouts of the relative abundance of the mRNA transcripts. Prosigna simultaneously measures the expression levels of 50 genes used in the PAM50 classification algorithm (Parker et al., 2009), 8 housekeeping genes used for signal normalization, 6 positive controls, and 8 negative controls in a single hybridization reaction, using nucleic acid probes designed specifically to those genes.The software algorithm produces a Prosigna Score (referred to as ROR Score or Risk of Recurrence Score in the literature (Dowsett et al., 2013)) based on the similarity of the expression profile to each PAM50 molecular subtype, as well as the gross pathological tumor size and a proliferation score computed from a subset of genes. Three risk categories (Low, Intermediate and High) were defined based on a study with over 1007 patient samples associating Prosigna score with long-term outcome. The required components for the Prosigna Assay include the RNA Isolation kit (manufactured by Roche), Prosigna reagents (Reference Sample, CodeSet, Prep Pack, Cartridge(s) and Prep Plate) and the instruments that comprise the nCounter Dx Analysis System; the Prep Station and Digital Analyzer. The test output is a patient specific report which includes a Prosigna Score (0-100) and risk category (low/intermediate/high) where indicated.