Genomic Health Presents Robust Analytical Validation Study Results of Oncotype SEQ™ Liquid Biopsy Mutation Panel

Data Presented for First Time at ESMO 2016 Congress Highlight Company's Commitment to Delivering Rigorous, Clinically Actionable Liquid-based Tests for Late-stage Cancer Patients

REDWOOD CITY, Calif., Oct. 11, 2016 /PRNewswire/ -- Genomic Health, Inc. GHDX today announced results from its successfully completed analytical validation study of Oncotype SEQ™ Liquid Select, which demonstrated that this liquid biopsy mutation panel is highly sensitive, specific and reproducible. To provide transparent and clinically meaningful performance standards, the analytical performance for Oncotype SEQ is reported on a per-sample basis rather than a per-DNA base measure. The data were presented at the European Society for Medical Oncology (ESMO) 2016 Congress in Copenhagen, Denmark.

"The high specificity, sensitivity and reproducibility of Oncotype SEQ validated in this study ensures reliable and actionable liquid biopsy test results that physicians can routinely use in clinical practice to help drive precision medicine and enable patients to make more informed treatment decisions," said Phil Febbo, M.D., chief medical officer, Genomic Health. "Delivered through our Oncotype IQ™ Genomic Intelligence Platform, the test is designed to address the needs of about 450,000 patients who recur or present with late-stage disease each year in the United States alone, reinforcing Genomic Health's industry-leading capability to optimize cancer treatment across the patient journey."

From a simple blood draw, Oncotype SEQ uses next-generation sequencing (NGS) to detect and analyze cell-free DNA from the tumor isolated from a patient's blood to examine the four main types of genomic alterations that are associated with malignant transformation and response or resistance to therapy. Genomic Health's proprietary liquid biopsy technology accounts for errors frequently associated with NGS to enable highly sensitive analysis of clinically relevant genomic alternations. Comprising a panel of 17 select genes, Oncotype SEQ is designed to report only clinically actionable results that can be directly used to inform the treatment of patients with stage IV solid tumors. The test focuses on genomic markers that have been included in the National Comprehensive Cancer Network (NCCN^®) guidelines or associated with sensitivity or resistance to FDA-approved therapies; the test can also match eligible patients with actively enrolling Phase II-IV clinical trials specific to their tumor type.

The validation study established the per-sample specificity of Oncotype SEQ to be greater than 99 percent. Sensitivity was also very high in that 95 percent of the time, the test was able to detect cell free DNA from the tumor present at 0.19-0.56 percent (depending on type of genetic alternation) of the total amount of cell free DNA in plasma. These levels represent the low frequency of tumor derived cell free DNA commonly found in the plasma of patients with metastatic cancer. Study results also demonstrated that Oncotype SEQ was highly reproducible by detecting more than 95 percent of all observed variants in each run.

Genomic Health has launched a global, multi-center clinical concordance study as part of the company's goal to establish further evidence to support adoption and reimbursement of Oncotype SEQ. The study, to be conducted at 25 sites in the United States, Asia and Europe, is being led by Lee S. Schwartzberg, M.D., chief, Division of Hematology and Oncology, University of Tennessee.

About Genomic Health
Genomic Health, Inc. GHDX is the world's leading provider of genomic-based diagnostic tests that help optimize cancer care by addressing the overtreatment of the disease, one of the greatest issues in healthcare today. With its Oncotype IQ™ Genomic Intelligence Platform, the company is applying its world-class scientific and commercial expertise and infrastructure to lead the translation of clinical and genomic big data into actionable results for treatment planning throughout the cancer patient journey, from diagnosis to treatment selection and monitoring. The Oncotype IQ portfolio of genomic tests and services currently consists of the company's flagship line of Oncotype DX gene expression tests that have been used to guide treatment decisions for more than 600,000 cancer patients worldwide. Genomic Health is expanding its test portfolio to include additional liquid- and tissue-based tests, including the recently launched Oncotype SEQ™ Liquid Select assay. The company is based in Redwood City, California, with international headquarters in Geneva, Switzerland. For more information, please visit, www.GenomicHealth.com and follow the company on Twitter: @GenomicHealth, Facebook, YouTube and LinkedIn.

This press release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. 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: our business model; the regulation of our tests; the applicability of clinical study results to actual outcomes; our ability to develop and commercialize new tests and expand into new markets domestically and internationally; the risk that we may not obtain or maintain sufficient levels of reimbursement, domestically or abroad; competition; unanticipated costs or delays in research and development efforts; our ability to obtain capital when needed; and the other risks and uncertainties set forth in our filings with the Securities and Exchange Commission, including the risks set forth in our Quarterly Report on Form 10-Q for the quarter ended June 30, 2016. These forward-looking statements speak only as of the date hereof. Genomic Health disclaims any obligation to update these forward-looking statements.

NOTE: The Genomic Health logo, Oncotype, Oncotype DX, Recurrence Score, DCIS Score, Oncotype SEQ and Oncotype IQ are trademarks or registered trademarks of Genomic Health, Inc. All other trademarks and service marks are the property of their respective owners.

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