Sequenom Announces Results of Screening Studies for Down Syndrome and Updates Development of Noninvasive Prenatal Diagnostics at Analyst and Investor Briefing

Sequenom, Inc. (NASDAQ:SQNM), a leading provider of genetic-analysis solutions, announced positive results from screening studies using the Company’s noninvasive circulating cell-free fetal (ccff) nucleic acid SEQureDx™ Technology, which enables the detection of fetal aneuploidy, including Down syndrome from maternal blood. At its analyst-and-investor briefing "The Future of Noninvasive Prenatal Diagnostics” held at the International Society of Prenatal Diagnostics (ISPD) conference in Vancouver, Canada, executives were joined by a panel of leading scientists and clinicians to discuss study results and updates in the development of noninvasive prenatal diagnostics. The Company reported that in blinded studies performed at Sequenom involving approximately 200 clinical samples collected both prospectively and retrospectively, its proprietary test for Down syndrome correctly identified 100% of all Down syndrome samples (i.e. sensitivity or detection rate), without any false-positive outcomes (i.e. specificity). Population coverage for the T21 test improved to at least 93% of the U.S. population. With currently available serum-testing options having detection rates between 70% to 90% and false-positive rates as high as 5%, SEQureDx Technology shows promise for significant performance advantages over the current paradigms for prenatal screening. The Company expects to continue its development activities through the end of 2008, at which time the Company will initiate transfer of the technology to laboratory partners. The Company plans to initiate a multi-site validation study consisting of several thousand samples in the fourth quarter this year and launch its Down syndrome test as a Laboratory Developed Test (LDT) in the U.S. in the first half 2009. "We are very pleased to be reporting substantial progress toward commercializing an important test to screen for Down syndrome that can be administered as early as late in the first trimester through a simple blood draw from the mother,” said Harry Stylli, Ph.D., Sequenom’s President and Chief Executive Officer. "Data from our blinded screening study for the detection of fetal aneuploidy indicate that the current version of our test has identified all Down syndrome samples without any false-positive outcomes. Also our coverage has improved to at least 93% of the U.S. population. Although these results require further validation in larger studies, such results using SEQureDxTM Technology can potentially transform current clinical practice for Down syndrome-risk assessment.” The studies conducted both prospectively and retrospectively, involved approximately 200 samples in both normal and high-risk patients. The blinded-prospective study involved 180 samples comprising 130 low-risk and 50 high-risk samples. The test correctly identified three Down syndrome samples without any false-positive outcomes. Of the 21 blinded samples analyzed retrospectively, the test correctly identified seven Down syndrome samples while also indicating no false-positive results. "A direct, noninvasive genetic assessment of fetal Down syndrome will result in far-better screening accuracy and would dramatically reduce the number of unnecessary, invasive diagnostic procedures that women undergo in current maternal serum-screening protocols. Improved detection rates, as reported by Sequenom in its assay optimization studies, exceed those with currently available screening models,” said Allan T. Bombard, M.D., a reproductive geneticist with more than two decades of experience in the field of prenatal screening and diagnosis. (Dr. Bombard serves as a Chief Medical Director at Sharp Mary Birch Hospital and is the Principal Investigator of the study.) "Moreover, having minimum false-positive results will significantly reduce the number of unnecessary confirmatory diagnostic tests, as well as the anxiety and complications associated with invasive procedures.” Currently available tests conducted during the first or second trimester of pregnancy use epigenetic markers associated with the Down syndrome phenotype that are characterized as "surrogate” markers as they are not directly related to the extra Number 21 chromosome. Different combinations of markers, measured at different times in pregnancy, constitute the multiple-marker approach to screening. These tests have detection rates of 70% to 90% with approximately a 5% false-positive rate, while also having inconsistent population coverage or ethnicity rates. The SEQureDx test uses a maternal blood sample drawn as early as the first trimester and identifies directly the extra Number 21 chromosome. Invasive procedures such as amniocentesis or chorionic villus sampling (CVS) carry risk of miscarriage and other risks to mother and fetus. "Current screening methods, using multiple ‘surrogate’ markers, are very good, but are unlikely to reach diagnostic potential,” said Jacob Canick, Ph.D., Professor of Pathology and Laboratory Medicine at Brown University Medical School. "In contrast, I am optimistic that tests using multiple-fetal RNA and DNA markers can be developed not only for Down syndrome, but for all clinically important aneuploidies, and it is reasonable to expect that such direct, noninvasive diagnostics could be done in the first trimester of pregnancy.” Sequenom’s analyst-and-investor-briefing event speakers included Alan Bombard, M.D., Chief Medical Officer at Sharp Mary Birch Hospital, who discussed current clinical practices for Down syndrome screening and diagnosis; Jacob Canick, Ph.D., Professor of Pathology and Laboratory Medicine at Brown University Medical School, who discussed methods for screening pregnancies for Down syndrome; Professor Dennis Lo, consultant to Sequenom and a leading researcher in prenatal diagnostics, who discussed the future of prenatal diagnosis; and Sequenom’s Senior Vice President of Research and Development Elizabeth Dragon, Ph.D., who reviewed progress with Sequenom’s SEQureDx Technology in developing a test for Down syndrome. A webcast of the event is available on the Company Web site at www.sequenom.com. Sequenom’s Proprietary Noninvasive Prenatal Diagnostics Sequenom’s commercial opportunities in prenatal diagnostics are built upon its SEQureDx technologies and are enabled by the pioneering inventions and associated intellectual property rights that it has exclusively licensed from Isis Innovation Ltd., the technology transfer company of the University of Oxford, as well as The Chinese University of Hong Kong. Sequenom’s portfolio of noninvasive prenatal diagnostic patent rights and patent applications is platform-independent, includes genetic-analysis methods using circulating cell-free fetal nucleic acids from maternal serum, plasma or whole blood, and also includes a portfolio of methylation and nucleic-acid markers. Sequenom holds exclusive rights in territories including the United States, Europe, Australia, Canada, Japan and Hong Kong. Sequenom is actively expanding its intellectual property position with new technology and new territories. Because Sequenom’s license rights are platform-independent, the rights provide exclusivity (with the narrow exception in Europe for RT-PCR-based Rhesus D tests) for development and commercialization of noninvasive prenatal screens and tests on any platform and are not limited to the Company’s MassARRAY platform. About SEQureDx Technology Sequenom’s SEQureDx Technology is a novel approach to genetic screening. Unlike current standards of harvesting placental tissue cells as is required for chorionic villus, or entering the uterus to sample the amniotic fluid surrounding the baby as is performed with amniocentesis, SEQureDx Technology extracts Fetal Nucleic Acid material safely and comfortably from a simple blood specimen collected from the mother to determine the genetic status of the fetus. This breakthrough suggests that effective screening may be accomplished in the future without the risks associated with disturbing the amniotic fluid that surrounds the baby in the uterus. In December 2007, the Company, through its laboratory partner, introduced a laboratory-developed RhD incompatibility test using RT-PCR in the United States. In February 2008, Sequenom announced progress with its noninvasive Trisomy 21 test based on multiple RNA fetal markers, including the PLAC4 gene as previously published by Dr. Dennis Lo, Chinese Hong Kong University. In these preliminary studies, data from more than 100 clinical plasma specimens of various ethnicities indicated that the development-stage Trisomy 21 test was approaching 85% (+/- 5%) ethnic coverage, more than 95% sensitivity and close to 99% specificity. About Down Syndrome Down syndrome is a chromosomal abnormality characterized by the presence of an extra copy of genetic material on the 21st chromosome, either in whole (Trisomy 21) or in part (such as due to translocations). The effects of the extra copy vary greatly among people, depending on the extent of the extra copy, genetic history and pure chance. In 2007, the American College of Obstetricians and Gynecologists (ACOG) endorsed guidelines that offer risk assessment to all pregnancies for fetal chromosomal abnormalities, including Down syndrome. The ACOG recommendation includes screening before the 20th week of pregnancy using a less-invasive screening option that includes ultrasound in conjunction with the measurement of certain blood hormones. It is estimated that approximately 70%, or 2.8 million, women undergo Down syndrome screening in the United States each year. About Sequenom Sequenom is committed to providing the best genetic-analysis products for research and the molecular-diagnostic markets. The Company makes available superior solutions for genomic science in biomedical research, livestock and agricultural applications and molecular medicine, as well as for various diagnostic markets, including noninvasive prenatal testing, oncology and infectious diseases. Sequenom’s proprietary MassARRAY system delivers reliable and specific data from complex biological samples and from genetic-target materials available only in trace amounts. Sequenom®, MassARRAY® and SEQureDx™ are trademarks of Sequenom, Inc. Except for the historical information contained herein, the matters set forth in this press release, including statements regarding the future performance, impact on healthcare, expectations, plans, and timelines for development, screening studies, validation studies, partnering and technology transfer, and commercialization of the Company’s SEQureDx Technology for detection of fetal aneuploidy including Down syndrome, are forward-looking statements within the meaning of the "safe harbor” provisions of the Private Securities Litigation Reform Act of 1995. These forward-looking statements are subject to risks and uncertainties that may cause actual results to differ materially, including the risks and uncertainties associated with demand for and market acceptance of Sequenom’s products, services, and technologies, new technology and product development and commercialization, reliance upon the collaborative efforts of other parties, research and development progress, competition, government regulation particularly with respect to diagnostic products and laboratory developed tests, obtaining or maintaining regulatory approvals, and other risks detailed from time to time in the Company’s SEC reports, including the Company’s Annual Report on Form 10-K for the year ended December 31, 2007 and subsequent periodic reports. These forward-looking statements are based on current information that is likely to change and speak only as of the date hereof. You are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date of this press release. All forward-looking statements are qualified in their entirety by this cautionary statement, and the Company undertakes no obligation to revise or update any forward-looking statement to reflect events or circumstances after the issuance of this press release.