CombiMatrix Study Published in Genetics in Medicine

Study Supports Follow-up Diagnostic Testing to Confirm Positive Results From Non-invasive Prenatal Testing

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| Source: CombiMatrix Corporation

IRVINE, Calif., Feb. 01, 2016 (GLOBE NEWSWIRE) -- CombiMatrix Corporation (NASDAQ:CBMX), a molecular diagnostics company specializing in DNA-based testing services for prenatal and postnatal developmental disorders and pre-implantation genetic screening services, announces the publication of data from a CombiMatrix study supporting the value of follow-up diagnostic testing to either confirm or rule out positive results for common chromosomal aneuploidies and microdeletion syndromes detected by non-invasive prenatal testing (NIPT). 

The data from the study appeared in the peer-reviewed Genetics in Medicine advance online publication (21 January 2016. doi:10.1038/gim.2015.196) submitted by Trilochan Sahoo, M.D., FACMG, CombiMatrix’s Vice President of Clinical Affairs and Director of Cytogenetics, in a letter to the editor entitled, “Expanding non-invasive prenatal testing to include microdeletions and segmental aneuploidy: cause for concern?” The letter provides “important and substantial addition” to the conclusion in a previously published article in Genetics in Medicine, “Maternal cell-free DNA-based screening for fetal microdeletion and the importance of careful diagnostic follow-up,” Yatsenko SA, et. al.

“Our study supports the need for extreme caution in the interpretation of NIPT due to higher-than-previously reported false positive rates compared with invasive testing and concern regarding the potential of over-representation of the positive predictive value for specific aneuploidies and microdeletions,” said Dr. Sahoo.  Common chromosomal fetal aneuploidies include Down (trisomy 21), Edwards (trisomy 18) and Patau (trisomy 13) syndromes, and common microdeletion syndromes are associated with conditions such as intellectual disability, seizures, autism spectrum disorder and neuropsychiatric disorder.

The CombiMatrix study included a review of the results of chromosomal microarrays and/or karyotype analysis following NIPT on 277 evaluable cases, showing a discordance rate of 20% and partial discordance rate of 11%.  The study included 25 cases in which NIPT showed a microdeletion or segmentation fetal aneuploidy.  The conclusion drawn in the Yatsenko, et. al, article was based on the observation of a single microdeletion case.

“The most significant and recent observation from our study showed a high rate of false positives for microdeletions,” continued Dr. Sahoo.  “This makes it extremely prudent to take a much more cautious approach to expanding NIPT for microdeletions with definitive testing such that we offer at CombiMatrix.”  Dr. Sahoo presented data from this study at the American Society of Human Genetics in October 2015.

“Major providers of NIPT are expanding beyond screening for common chromosomal fetal aneuploidies to common microdeletion syndrome and the results of these tests can lead to important decisions for women and their families,” said Mark McDonough, President and Chief Executive Officer of CombiMatrix.  “We recommend extensive pretest genetic counseling with a complete discussion of the benefits and limitations of screening versus diagnostic testing. This is particularly important for patients determined as low-risk for abnormalities in which abnormalities are detected with NIPT and for patients considered high-risk with normal NIPT results.”

Highlights of the 25 cases in which the CombiMatrix study compared NIPT results indicating aneuploidy and microdeletions with microarray and/or karyotyping results included:

  • Discordance in 5 out of 7 cases with deletion 22q11.21; 5 out of 6 cases with deletion 5p; 3 out of 4 cases with deletion 1p36; and 1 out of 1 case with deletion 4p.
     
  • Concordance in 1 case each identifying 15q deletion, a 9p duplication [confirmed to be an isodicentric (9p)] and a 13q deletion.
     
  • Partial concordance in single cases as follows:
     
    • NIPT was suggestive of both 18p and 18q terminal deletions, diagnostic testing revealed only a deletion of 14 Mb at 18p11.32p11.21.
    • NIPT suggestive of trisomy 18q, diagnostic testing showed a duplication of 18p11.21q23 that was further characterized to be a translocation of the duplicated segment to the p-arm of one chromosome 13, resulting in trisomy for the 18p11.21q23 segment.
    • NIPT results indicated a “partial deletion of 21q,” diagnostic testing revealed a duplication of 9.2 Mb at 21q11.2-q21.1 that was inserted at 14p11.2.
       
  • NIPT results were inconclusive for chromosome 13, microarray testing showed a large region of allelic homozygosity for chromosome 13.

About CombiMatrix Corporation

CombiMatrix Corporation provides valuable molecular diagnostic solutions and comprehensive clinical support to foster the highest quality in patient care. CombiMatrix specializes in prenatal diagnostics, miscarriage analysis for recurrent pregnancy loss, pediatric genetics and pre-implantation genetic screening, offering DNA-based testing for the detection of genetic abnormalities beyond what can be identified through traditional methodologies. CombiMatrix performs genetic testing utilizing a variety of advanced cytogenomic techniques, including chromosomal microarray, standardized and customized fluorescence in situ hybridization (FISH) and high-resolution karyotyping. CombiMatrix is dedicated to providing high-level clinical support for healthcare professionals in order to help them incorporate the results of complex genetic testing into patient-centered medical decision making. Additional information about CombiMatrix is available at www.combimatrix.com or by calling (800) 710-0624.

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

This press 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, speak only as of the date hereof and are subject to change. All statements, other than statements of historical fact included in this press release, are forward-looking statements. Forward-looking statements can often be identified by words such as "anticipates," "expects," "intends," "plans," "goal," "predicts," "believes," "seeks," "estimates," "may," "will," "should," "would," "could," "potential," "continue," "ongoing," similar expressions, and variations or negatives of these words and include, but are not limited to, statements regarding projected results of operations and management's future business, operational and strategic plans, recruiting efforts and test menu expansion. These forward-looking statements are not guarantees of future results and are subject to risks, uncertainties and assumptions that could cause our actual results to differ materially and adversely from those expressed in any forward-looking statement. The risks and uncertainties referred to above include, but are not limited to: whether follow-up diagnostic testing is more reliable than NIPT; whether the CombiMatrix study contains errors or could be contradicted or disproven by other studies; our ability to successfully expand the base of our customers and strategic partners, add to the menu of our diagnostic tests, develop and introduce new tests and related reports, expand and improve our current suite of services, optimize the reimbursements received for our microarray testing services, and increase operating margins by improving overall productivity and expanding sales volumes; our ability to successfully accelerate sales, steadily increase the size of our customer rosters in both prenatal and developmental genetic testing markets; our ability to attract and retain a qualified sales force in wider geographies; our ability to ramp production from our sales force and our strategic partners; rapid technological change in our markets; changes in demand for our future services; legislative, regulatory and competitive developments; the outcome of pending litigation; general economic conditions; and various other factors. Further information on potential factors that could affect our financial results is included in our Annual Report on Form 10-K, Quarterly Reports of Form 10-Q, and in other filings with the Securities and Exchange Commission. We undertake no obligation to revise or update publicly any forward-looking statements for any reason, except as required by law.

Company Contact:
Mark McDonough
President & CEO, CombiMatrix Corporation
(949) 753-0624

Investor Relations Contact:
LHA
Jody Cain
(310) 691-7100
jcain@lhai.com