NanoString Technologies Inc. Presents Positive Results From Multisite Analytical Validation Study of Prosigna Breast Cancer
Published: Mar 06, 2013
Prosigna’s intended use is for risk assessment in post-menopausal women with stage I and II hormone receptor positive (HR+) breast cancer. Prosigna provides a subtype classification based on the fundamental biology of an individual’s breast tumor (referred to as intrinsic subtyping), and a prognostic score ranging from zero to 100 (referred to as the risk of recurrence, or ROR, score). The Prosigna assay is approved for use by healthcare professionals in the European Union and Israel, and was launched commercially in those countries in February 2013.
The objective of this study was to assess the analytical robustness of Prosigna when used in qualified clinical laboratories. Prosigna assays were run independently at three different testing sites by a total of six different operators using three different reagent lots. Reproducibility was assessed by testing multiple tissue sections from each of 43 Formalin-Fixed, Paraffin Embedded (FFPE) breast tumor blocks across the three sites following review of hematoxylin and eosin (H&E) stained slides by an independent pathologist at each site. The magnitude of different sources of analytical variation in the assay were further characterized by testing five pooled breast tumor RNA samples more than 100 times each.
When starting with FFPE tissue blocks, this study showed that Prosigna’s reproducibility, including all analytical and pre-analytical variables, was characterized by a total standard deviation of just 2.9 ROR units on a zero-to-100 scale. In addition, there was an average site-to-site concordance of 97% in reporting of intrinsic subtype. When starting from pooled RNA, Prosigna’s precision was characterized by a total standard deviation of less than 1 ROR unit.
“These data demonstrate the analytical robustness of the Prosigna assay starting from FFPE tissue blocks across multiple testing sites, pathologists and operators,” said Torsten Nielsen, MD, PhD, pathologist at the BC Cancer Agency and lead pathology investigator of this study. “We found excellent reproducibility in measurement of the ROR score with no detectable site-to-site or operator-to-operator variance. These results support the ability of the Prosigna assay to generate consistent results when used in qualified hospital labs in different cities and countries. We also found the technology was very easy to use.” Dr. Nielsen is also a Professor of Pathology at the University of British Columbia.
The Prosigna assay requires minimal hands-on time and can be offered through qualified pathology laboratories, empowering oncologists and pathologists to manage the diagnostic evaluation of breast cancer patients locally and using the laboratory infrastructure already in place. The Prosigna assay runs on NanoString’s proprietary nCounter system, which offers a simple, reproducible and cost-effective way to profile many genes simultaneously with high sensitivity and precision. The Prosigna assay is approved for use by healthcare professionals in the European Union and Israel; it is not available in North America. The nCounter Analysis System is currently available for “Research Use Only” in North America.
“The results of this study support diagnostic testing on a distributed basis in the European Union and Israel using our nCounter-based diagnostic platform, which can be run by pathologists in any qualified laboratory,” said Brad Gray, President and Chief Executive Officer of NanoString Technologies. “Together with our two clinical validation studies totaling over 2,400 patients, these results further strengthen the body of evidence supporting our recent launch of the Prosigna assay in the European Union and Israel.”
About the Prosigna™ Breast Cancer Prognostic Gene Signature Assay
Based on the PAM50 gene signature initially discovered by Charles Perou, Ph.D. and colleagues, the Prosigna assay provides a subtype classification based on the fundamental biology of an individual’s breast tumor (referred to as intrinsic subtyping), and a prognostic score (referred to as the risk of recurrence, or ROR, score). The ROR score estimates the probability of cancer recurrence within 10 years in post-menopausal women with hormone receptor-positive early-stage breast cancer who have been treated with endocrine therapy alone. The Prosigna assay was validated in two clinical studies with more than 2,400 patient samples and results were presented at the 2011 and 2012 San Antonio Breast Cancer Symposium.
The intended use for Prosigna™ Breast Cancer Prognostic Gene Signature Assay is risk assessment in early-stage post-menopausal women with stage I and II hormone receptor positive (HR+) breast cancer. The Prosigna assay is approved for use by healthcare professionals in the European Union and Israel; it is not available in North America. For more information, please visit www.prosigna.com.
About NanoString Technologies, Inc.
NanoString Technologies is a privately held provider of life science tools for translational research and developer of molecular diagnostic products. The company’s nCounter® Analysis System, has been employed in basic and translational research since it was first introduced in 2008 and cited in more than 180 peer-reviewed publications, has also now been optimized as a diagnostic platform. The system 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, which has been launched in the EU and Israel, is the first in vitro diagnostic kit to be marketed through the company’s recently formed diagnostics business.
The nCounter Analysis System is currently available for “Research Use Only” in North America. For more information, please visit www.nanostring.com.
The NanoString Technologies logo, NanoString, NanoString Technologies and nCounter are registered trademarks, and Prosigna is a trademark, of NanoString Technologies, Inc.
For NanoString Technologies
Maurissa Messier, 760-539-7417