CombiMatrix Announces Positive Results From Expanded HerScan Study

Company Reaffirms Its Regulatory Stance in Offering HerScan as a Laboratory Developed Test (LDT) in Response to Genentech FDA Citizen Petition Filing


MUKILTEO, Wash., Dec. 18, 2008 (GLOBE NEWSWIRE) -- CombiMatrix Corporation (Nasdaq:CBMX) today announced that expanded study results on the company's HerScan(tm) array comparative genomic hybridization (array CGH) test demonstrated 97% concordance with fluorescent in situ hybridization (FISH) enumeration of the Her2 gene locus. The evaluation was based on 100 additional breast cancer cases and was presented this past week at the 31st Annual San Antonio Breast Cancer Symposium.

"These data further validate that when chromosome resolution is insufficient to fully elucidate causality, or in breast cancers where cell culture conditions preclude effective chromosomal preparations, our array CGH tests provide a robust clinical tool for capturing the genomic equivalent of an incredibly high resolution chromosome karyotype," said Dr. Mansoor Mohammed, President and CEO of Combimatrix Molecular Diagnostics (CMDX). "Monitoring single locus events, such as the amplification of the Her2 gene, is critical in the diagnosis of a cancer, as is the analysis of downstream chromosomal alterations that may be secondary to the cause of the cancer but crucial to appreciation of the evolution of the cancer. The latter is simply NOT deducible by a single locus FISH probe, but readily inferable from the results of our array CGH data."

"These data also validate our stance that a comprehensive understanding of the chromosomal makeup of a cancer cell is indispensable, and has always been the hallmark of prudent laboratory developed tests (LDTs) for cancer diagnostics," said Dr. Amit Kumar, President and CEO of CombiMatrix Corporation. "Recently Genentech filed a Citizen Petition asking the U.S. Food and Drug Administration (FDA) to re-evaluate its regulation of Laboratory Developed Tests (LDTs), including our HerScan test. While we agree with Genentech on the key points in the petition, we were disappointed that Genentech did not contact us or evaluate our validation data before mentioning our test in their petition. The FDA in its guidance documents has clearly stated that cytogenetic tests, of which HerScan is one, are appropriate for operation as LDTs. Our HerScan test fully complies with regulations of CLIA (Clinical Laboratory Improvements Amendments), CAP (College of American Pathologists), and ASCO (American Society of Clinical Oncology). Furthermore, the FDA issued us a letter stating that our tests can be run as LDTs. CombiMatrix is comfortable with the regulatory status of all of its array tests, and will continue to launch more, such as its recently announced prostate cancer test. While we do feel that there are certain tests on the market that are being operated as LDTs and should not be, we feel the FDA is appropriately exercising its discretion on regulatory matters. We have recently contacted Genentech to engage them in a discussion of our test, and we encourage patients, physicians, and regulators to contact us for more detailed data on any of our tests. Our commitment is always to the patient, and our goal is to utilize the best technology available to provide information that enables the best care for each individual patient at the personalized genetic level."

Following is a link to the letter from FDA received by CombiMatrix, supporting the regulatory status of its testing approach:

http://files.shareholder.com/downloads/CBMX/488936050x0x118569/52706a70-87ae-4fa2-af9c-4613c4bc699c/118569.pdf

Further Details on Expanded HerScan Study

FISH enumeration of the Her2 gene, together with immunohistochemical (IHC) staining of its protein product, are collectively considered the current gold standards in evaluation of Her2 status and are used in determining suitability for Herceptin therapy in breast cancer patients. However, numerous independent studies have highlighted the subjectivity of these methodologies and have spawned a concerted effort to develop methodologies that are capable of more objectively evaluating the Her2 copy number status in breast cancer patients. The recent data presented by CombiMatrix validate that its HerScan test can in fact deliver an accurate and objective enumeration of the Her2 gene locus.

Moreover, data from the expanded clinical validation of the HerScan test further highlight a significant flaw in the traditional approach of FISH enumeration of the Her2 gene. Currently, Her2 gene copy number status is presented as a ratio between the fluorescent signals observed for the Her2 gene locus and that of a control probe for chromosome 17 (on which the Her2 gene resides). The latter approach has led to the assumption that gains in the copy number of the Her2 gene occur through two routes: i) Her2 locus-specific amplification or ii) the accumulation of extra copies of the entire chromosome 17. The latter is referred to as polysomy 17 and has typically not been considered "true" amplification. However, data from the HerScan study conclusively demonstrate that polysomy of chromosome 17 is likely NOT a mode of Her2 copy number gain in breast cancer and that this erroneous interpretation stems from the inherent limitations of the standard FISH test, which precludes a whole genome or comprehensive chromosomal evaluation. In contrast, the HerScan test correctly demonstrated that complex amplifications along the length of chromosome 17 independently affect both chromosome loci queried by the standard FISH approach leading to the erroneous assumption of the presence of polysomy 17.

Furthermore, the HerScan test is not confined to the enumeration of the Her2 locus. Rather, it provides a comprehensive molecular cytogenetic evaluation of the entire breast tumor genome since the array CGH basis of the HerScan test is essentially a genomic or molecular karyotype. Accordingly, for the first time in breast cancer diagnostics the HerScan test facilitates the very standard that has come to be expected in the cytogenetic diagnosis and evaluation of any other cancer.

"As a clinical pathologist, I am convinced that this more comprehensive evaluation of breast cancer tumors will ultimately serve to provide better diagnostic decisions for our patients," noted Dr. Shelly Gunn, Medical Director of CMDX. "As Dr. Mohammed has noted, in the diagnosis of any cancer I can think of, whenever an analysis of the chromosome complement is possible, it is invariably required. Whenever limitations preclude chromosome preparations, every effort is made to extract the equivalent data. With the ability of array CGH and the HerScan test to provide the latter, it is in my opinion, wholly inadequate and inconsistent with basic laboratory practice to limit the diagnosis of breast cancers to a single locus FISH test."

ABOUT COMBIMATRIX CORPORATION

We are a diversified biotechnology business, through the development of proprietary technologies, products and services in the areas of drug development, genetic analysis, molecular diagnostics, nanotechnology research, defense and homeland security markets, as well as other potential markets where our products and services could be utilized. The technologies we have developed include a platform technology to rapidly produce customizable, in-situ synthesized, oligonucleotide arrays for use in identifying and determining the roles of genes, gene mutations and proteins. This technology has a wide range of potential applications in the areas of genomics, proteomics, biosensors, drug discovery, drug development, diagnostics, combinatorial chemistry, material sciences and nanotechnology. We have also developed the capabilities of producing arrays that utilize bacterial artificial chromosomes on our arrays, also enabling genetic analysis. Other technologies include proprietary molecular synthesis and screening methods for the discovery of potential new drugs. Combimatrix Diagnostics, Inc. ("CMDX"), our wholly owned subsidiary located in Irvine, California, has developed capabilities of producing arrays that utilize bacterial artificial chromosomes, which also enable genetic analysis.

Additional information about CombiMatrix Corporation is available at www.combimatrix.com or by calling 1-800-985 CBMX (2269). Additional information about our laboratory, Combimatrix Molecular Diagnostics, is available at www.cmdiagnostics.com or by calling 1-800-710-0624.

Safe Harbor Statement under the Private Securities Litigation Reform Act of 1995

This news release contains forward-looking statements within the meaning of the "safe harbor" provisions of the Private Securities Litigation Reform Act of 1995. These statements are based upon our current expectations and speak only as of the date hereof. Our actual results may differ materially and adversely from those expressed in any forward-looking statements as a result of various factors and uncertainties, including the recent economic slowdown affecting technology companies, our ability to successfully develop products, rapid technological change in our markets, changes in demand for our future products, legislative, regulatory, and competitive developments, and general economic conditions. Our Annual Report on Form 10-K, recent and forthcoming Quarterly Reports on Form 10-Q, recent Current Reports on Forms 8-K and 8-K/A, and other SEC filings discuss some of the important risk factors that may affect our business, results of operations, and financial condition. We undertake no obligation to revise or update publicly any forward-looking statements for any reason.



            

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