REDWOOD CITY, Calif., Feb. 23, 2012 /PRNewswire/ -- Verinata Health, Inc., a privately-held company dedicated to maternal and fetal health, today published the full data from its prospective, blinded, multicenter clinical validation study to detect fetal chromosomal aneuploidies across the entire genome, including cases of fetal mosaicism and translocations. The publication, entitled "Genome-Wide Fetal Aneuploidy Detection by Maternal Plasma DNA Sequencing," was selected as Editor's Choice of the peer-reviewed journal, Obstetrics & Gynecology (Green Journal), the official publication of the American College of Obstetricians and Gynecologists. Full study results will appear today after 5:00 p.m. Eastern Time in the online version of the journal (http://journals.lww.com/greenjournal/pages/default.aspx). A print version will also be available in the May 2012 issue.
"When we designed this study, it was imperative that it emulate actual clinical practice, including all high risk pregnant women, and importantly, detecting aneuploidy across the entire genome, where the genetic information about the fetus is unknown prior to this test," said Caren L. Mason, chief executive officer of Verinata Health. "The clinical study demonstrated 100% specificity (no false positives) in the most prevalent trisomies. We will work with maternal fetal medicine specialists, ObGyns and genetic counselors to incorporate our verifi prenatal test into clinical practice, offering a non-invasive choice to accurately detect the three major fetal autosomal chromosome aneuploidies. We are thrilled to have the full publication broadly available to readers to support the launch of the verifi prenatal test."
Verinata's proprietary verifi non-invasive prenatal test will include the detection of Down syndrome (trisomy 21), Edwards syndrome (trisomy 18) and Patau syndrome (trisomy 13) in the initial launch configuration. Additional technical papers covering Verinata's methods in practice and continuing improvement in sequencing results are pending. The verifi prenatal test will be available to clinicians in the United States on March 1 and will include simplified sample collection methods, streamlined test reporting and less than a one percent no call rate. Verinata intends to expand the capabilities of the verifi prenatal test later in 2012.
"The accuracy of the early results provided by the verifi prenatal test suggest that it can be incorporated into clinical practice to eliminate false positives and reduce unnecessary invasive procedures, thereby making prenatal testing safer for pregnant women," said Diana W. Bianchi, M.D., of the Mother Infant Research Institute at Tufts Medical Center, and lead author of the publication. "Beyond the superior results for the three most common trisomies when compared to serum screening, it is significant that the study included samples from women who became pregnant through assisted reproduction techniques (ART), detected mosaic and translocation forms of the major trisomies, and demonstrated the ability to correctly classify cases of monosomy X (Turner syndrome) while showing promise for the detection of other sex chromosome abnormalities."
Full Clinical Study Data
The prospective, blinded study included 2882 samples of maternal blood collected from over 60 sites in the United States under approved institutional protocols. All singleton pregnancies with any abnormal karyotype and a balance of subjects with euploid karyotypes were randomly selected by an independent biostatistician. The objective of the Verinata clinical validation study was to prospectively determine the diagnostic accuracy of massively parallel sequencing (MPS) to detect whole chromosome fetal aneuploidy. Five hundred thirty-two samples were analyzed to detect fetal aneuploidies across the genome using MPS in combination with Verinata Health's proprietary algorithm. Results showed that Verinata's test correctly identified all 89 cases of trisomy 21 (T21) with 100 percent sensitivity and specificity. In addition, the test detected trisomy 18 (T18) and trisomy 13 (T13) with 100 percent specificity for both, and 97.2 percent (35/36) and 78.6 percent (11/14) sensitivity, respectively. Female sex was correctly classified in 99.6 percent (232/233) of samples, and male sex accurately detected in all cases (184/184). The test also accurately detected monosomy X (Turner syndrome), mosaicism for both T21 (3/3) and T18 (1/1), two cases of other autosomal trisomies (20 and 16), and additional sex chromosome aneuploidies (XXX, XXY and XYY).
Subset of Study for Women who Conceived through In Vitro Fertilization
Thirty-eight women who conceived using in vitro fertilization (IVF) techniques were included in the study, as they are often at high risk for aneuploidy. Seventeen (17/38) tested positive for aneuploidy, with no false negatives or false positives (100 percent sensitivity and specificity, respectively) for this group of women.
In addition to Bianchi, additional authors include Lawrence Platt, David Geffen School of Medicine at UCLA, Obstetrics and Gynecology, Los Angeles, Calif.; James Goldberg, San Francisco Perinatal Associates, Prenatal Diagnosis Center, San Francisco, Calif.; Alfred Abuhamad, Eastern Virginia Medical School, Department of Obstetrics and Gynecology, Norfolk, Va.; Richard Rava, Verinata Health, Inc., Research & Development, Redwood City, Calif.; and Amy Sehnert, Verinata Health, Inc., Clinical Research, Redwood City, Calif. on behalf of the MELISSA study group.
About Massively Parallel Sequencing for Non-Invasive Prenatal Testing
Aneuploidy is an abnormal number of chromosomes and a common cause of developmental and physical disabilities. Because a single tube of maternal blood contains billions of cell free DNA fragments from both the mother and the fetus, aneuploidies can be detected from the cell free DNA. MPS allows millions of these DNA fragments to be sequenced at the same time (i.e. the order of the nucleotides (adenine (A), cytosine (C), guanine (G) and thymine (T) determined)) and their unique locations within the genome to be determined. By counting the number of sequence fragments that are identified on each chromosome, and corrected for variations in the sequencing process through Verinata's proprietary method, the over- or under-representation of any chromosome in the cell free DNA mixture can be determined. Using Verinata's proprietary algorithm, if a specific chromosome is substantially over-represented in the DNA sequence, this indicates that the fetus has extra copies of a chromosome instead of the expected two. Under-representation of sequence indicates a monosomy (one copy of a chromosome). Consequently, Verinata's technology can potentially detect the presence of any chromosomal aneuploidy across the genome utilizing MPS.
Verinata Health, Inc.
Verinata is driven by a sole, extraordinary purpose maternal and fetal health. Our initial focus is to develop and offer non-invasive tests for early identification of fetal chromosomal abnormalities using our proprietary technologies. We aim to reduce the anxiety associated with today's multi-step process, the unacceptable false-positive rates, the non-specific and sometimes confusing results of current prenatal screening methods, as well as the risk of current invasive procedures. In support of national guidelines recommending first trimester aneuploidy risk assessment, we believe women who desire such an assessment should be offered a single blood draw test with a definitive result. Verinata has completed its blinded pivotal study to clinically validate the sensitivity and specificity of its first prenatal test. The verifi prenatal test is a non-invasive assay for the determination of the three primary chromosomal aneuploidies for trisomies 21, 18 and 13. For more information about Verinata, please go to www.verinata.com.
SOURCE Verinata Health, Inc.