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Newly Published Analytical Validation Study Shows Precision and Reproducibility of PAM50-Based Prosigna Breast Cancer Assay in Multiple Clinical Testing Laboratories
[March 13, 2014]

Newly Published Analytical Validation Study Shows Precision and Reproducibility of PAM50-Based Prosigna Breast Cancer Assay in Multiple Clinical Testing Laboratories


SEATTLE --(Business Wire)--

NanoString Technologies, Inc., (NASDAQ:NSTG) a provider of life science tools for translational research and molecular diagnostic products, today announced that a study published online in the journal BMC Cancer demonstrates the analytical validity of the PAM50-based Prosigna Breast Cancer Prognostic Gene Signature Assay. Based on highly concordant results across multiple clinical laboratory sites, technicians, and manufacturing lots of Prosigna reagents, the authors concluded that the study provides a strong body of evidence supporting the decentralized use of the Prosigna Assay on the nCounter Dx Analysis System as a prognostic tool for the risk of recurrence (ROR) in selected breast cancer patients.

The study, titled, "Analytic Validation of the PAM50 based Prosigna Breast Cancer Prognostic Gene Signature Assay and nCounter Analysis System Using Formalin Fixed Paraffin-Embedded Breast Tumor Specimens" was conducted by researchers from the British Columbia Cancer Agency and Washington University and can be found online at: http://www.biomedcentral.com/1471-2407/14/177/abstract.

"To date, multi-gene breast cancer clinical assays have largely been limited to centralized reference laboratories due to the complexity of performing these tests," said Torsten Nielsen, Professor of Pathology based at the British Columbia Cancer Agency and lead author on the publication. "Results from this new study demonstrate that the Prosigna assay has been shown to have both analytic and clinical validity, as required by the EGAPP (Evaluation of Genomic Applications in Practice and Prevention) working-group Standards."

The aim of this study was to assess the analytic robustness of the Prosigna Assay run on the nCounter Dx Analysis System at qualified laboratories. Analytic precision was evaluated from 540 replicate assays of five tumor RNA samples (108 replicates per sample), resulting in less than a one-point standard deviation in ROR score on a 0-100 point scale, and 100 percent site-to-site concordance in reporting subtype and risk group results. Analytic reproducibility was established by assaying 43 tissue samples at multiple laboratories including all sources of variation from tissue review by a local pathologist through to assay results. The results were highly reproducible and, importantly, there was a negligible contribution of multiple operators and sites to the overall variance in the ROR score.

"The results from this analytical validation study demonstrate that the Prosigna Assay on the nCounter Dx Analysis System is user friendly and that local laboratory pathologists can generate precise and reproducible results with the Prosigna Assay," said Brad Gray, President and Chief Executive Officer of NanoString Technologies. "This publication will be an important element in our submissions to payers, confirming analytic reproducibility and, together with our body of clinical data and FDA clearance, demonstrating the strong rationale for Prosigna reimbursement."

Breast Cancer Prognostic Gene Signature Assay and nCounter® Dx Analysis System



The Prosigna Assay provides a risk category and numerical score for assessment of the risk of distant recurrence of disease at 10 years in postmenopausal women with node-negative (Stage I or II) or node-positive (Stage II), hormone receptor-positive (HR+) breast cancer. Based on the PAM50 gene signature initially discovered by Charles Perou, Ph.D. and colleagues, the Prosigna Assay is an in vitro diagnostic tool that utilizes gene expression data weighted together with clinical variables to generate a risk category and numerical score to assess a patient's risk of distant recurrence of disease. The Prosigna Assay measures gene expression levels of RNA extracted from formalin-fixed paraffin embedded (FFPE) breast tumor tissue previously diagnosed as invasive breast carcinoma.

The Prosigna Assay requires minimal hands-on time and runs on NanoString's proprietary nCounter® Dx Analysis System, which offers a reproducible and cost-effective way to profile many genes simultaneously with high sensitivity and precision.


The nCounter Dx Analysis System is a highly automated and easy-to-use platform that utilizes a novel digital barcoding chemistry to deliver high precision multiplexed assays. The system is available in the multi-mode FLEX configuration, which is designed to meet the needs of high-complexity clinical laboratories seeking a single platform with the flexibility to run the Prosigna Breast Cancer Assay and, when operated in the "Life Sciences" mode, process translational research experiments and multiplexed assays developed by the laboratory.

In the United States, the Prosigna Assay is available for diagnostic use when ordered by a physician. The Prosigna Assay has been CE-marked and is available for use by healthcare professionals in the European Union and other countries that recognize the CE Mark and in which Prosigna is registered.

The Prosigna Breast Cancer Prognostic Gene Signature Assay Intended Use:

In the U.S., the Prosigna Assay is indicated in female breast cancer patients who have undergone surgery in conjunction with locoregional treatment consistent with standard of care, either as:

(1) a prognostic indicator for distant recurrence-free survival at 10 years in postmenopausal women with Hormone Receptor-Positive (HR+), lymph node-negative, Stage I or II breast cancer to be treated with adjuvant endocrine therapy alone, when used in conjunction with other clinicopathological factors or (2) a prognostic indicator for distant recurrence-free survival at 10 years in postmenopausal women with Hormone Receptor-Positive (HR+), lymph node-positive (1-3 nodes), Stage II breast cancer to be treated with adjuvant endocrine therapy alone, when used in conjunction with other clinicopathological factors. The device is not intended for patients with 4 or more positive nodes.

Special Conditions for Use:

The Prosigna Assay is not intended for diagnosis, to predict or detect response to therapy, or to help select the optimal therapy for patients.

For more information, please visit www.prosigna.com.

About NanoString Technologies, Inc.

NanoString Technologies provides life science tools for translational research and molecular diagnostic products. The company's nCounter® Analysis System, which has been employed in basic and translational research since it was first introduced in 2008 and cited in more than 360 peer-reviewed publications, has also now been applied to diagnostic use as the nCounter Dx Analysis System. The company's technology offers a cost-effective way to easily profile the expression of hundreds of genes, miRNAs, or copy number variations, simultaneously with high sensitivity and precision. The company's technology enables a wide variety of basic research and translational medicine applications, including biomarker discovery and validation. The nCounter-based Prosigna Breast Cancer Prognostic Gene Signature Assay is the first in vitro diagnostic assay to be marketed through the company's diagnostics business. The nCounter Dx Analysis System is FDA 510(k) cleared for use with the Prosigna Breast Cancer Prognostic Gene Signature Assay. To date, it has not been cleared by the FDA for other indications or for use with other assays.

For more information, please visit www.nanostring.com.

Forward-Looking Statements

This press release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, including statements regarding the ability of the published data to support decentralized use of the nCounter Dx Analysis System and the Prosigna Assay and reimbursement for the related testing services. Forward-looking statements are subject to risks and uncertainties that could cause actual results to differ materially and reported results should not be considered as an indication of future performance. These risks and uncertainties include, but are not limited to: risks associated with keeping pace with rapidly changing technology and customer requirements; risks regarding the company's ability to successfully introduce new products; risks that new market opportunities may not develop as quickly as expected; risks associated with competition in marketing and selling products; risks of increased regulatory requirements; risks associated with obtaining reimbursement coverage for Prosigna; as well as the other risks set forth in the company's filings with the Securities and Exchange Commission. These forward-looking statements speak only as of the date hereof. NanoString Technologies disclaims any obligation to update these forward-looking statements.

The NanoString Technologies logo, NanoString, NanoString Technologies, and nCounter are registered trademarks, and Prosigna is a trademark of NanoString Technologies, Inc.


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