Natera Announces Publication of Clinical Experience Study with 18,984 Twin Pregnancies Supporting Excellent Performance of Panoramatm NIPT

Study aligns with Natera's longstanding commitment to generate robust, real-world clinical evidence and highlights unique capabilities of Panorama SNP-based NIPT

AUSTIN, Texas, Dec. 6, 2022 /PRNewswire/ -- Natera, Inc. (NASDAQ: NTRA), a global leader in cell-free DNA testing, today announced the publication in Prenatal Diagnosis of a clinical experience study in twin pregnancies featuring its Panorama single nucleotide polymorphism (SNP)-based noninvasive prenatal test (NIPT). These real-world results are consistent with previously reported performance of NIPT in twins, and reinforce the importance of Panorama's unique ability to determine zygosity and incorporate this information into risk assessments.

In this study, from a pool of 18,984 twin pregnancy results over a 27-month period in Natera's laboratory, investigators sought clinical outcomes from all cases reported as high-risk. Outcomes were obtained for 105 high-risk cases, representing 51.2% of the reported high-risk results. Key findings include:

• Across all twins with cytogenetic confirmation, the positive predictive value (PPV) of screening for trisomy 21 was 88.7%. When cases with findings suggestive of aneuploidy are included, the PPV for trisomy 21 was 90.4%.
• Dizygotic (DZ) twin cases confirmed cytogenetically had an estimated PPV of 88.1% for trisomy 21, and 85% for all aneuploidies, the first time NIPT PPVs have been reported specifically for DZ twins.
• Monozygotic (MZ) twin cases, both those confirmed cytogenetically and with findings suggestive of aneuploidy, had a PPV of 100% for trisomy 21 and trisomy 18.
• This study provides additional evidence to earlier findings that aneuploidy rates are higher in DZ than in MZ twin pregnancies.¹ In this study, DZ twins had a positive call rate 8-fold higher than MZ twins.

"This study provides real-world evidence regarding the performance of SNP-based NIPT in twin pregnancies, which account for about 1 in 30 live births in the U.S.²," said Herman Hedriana, MD, MFM, professor of clinical obstetrics and gynecology, director of Maternal-Fetal Medicine at UC Davis Health and senior author of the study. "The results support the use of SNP-based NIPT as a first-line screening test for aneuploidy in twins with the added benefit of determining zygosity, which can assist with the early detection of complications of monochorionic twin gestations, such as twin-to-twin transfusion syndrome."

Panorama is the only NIPT that can assess zygosity in twin pregnancies and report individual fetal fractions in DZ twins as early as nine weeks' gestation.  In 2020, the International Society for Prenatal Diagnosis (ISPD) recommended NIPT as a first-line screening test for common chromosomal conditions in twin pregnancies due to "sufficient evidence showing high detection and low false positive rates with high predictive values". ISPD also emphasized the importance of laboratories reporting zygosity and assessing individual fetal fraction in DZ twins for the interpretation of test results.³ In the same year, a joint guideline from the American College of Obstetricians and Gynecologists (ACOG) and the Society for Maternal-Fetal Medicine (SMFM) noted that NIPT can be performed in twins and highlighted the importance of adequate individual fetal fraction measurements to enable reliable results.⁴

"Natera is committed to generating evidence regarding the real-world performance of our testing. Panorama has been the subject of more than 30 peer-reviewed publications of over 1.3 million patients, including several large studies featuring rigorous follow-up to validate test performance with actual clinical outcomes," said Sheetal Parmar, VP of medical affairs, women's health at Natera. "We are pleased to share this additional evidence and we look forward to continuing to positively impact the management of twin pregnancies."

Panorama screens for severe genetic disorders as early as nine weeks into pregnancy. The test uses a unique single-nucleotide polymorphism (SNP)-based technology to analyze fetal (placental) DNA obtained through a blood draw from the mother. It is the only commercially available NIPT that differentiates between maternal and fetal DNA to assess the risk of aneuploidies. Panorama has been the subject of more than 30 peer-reviewed publications of over 1.3 million patients. Panorama has been developed and its performance characteristics determined by Natera, the CLIA-certified laboratory performing the test. The test has not been cleared or approved by the US Food and Drug Administration (FDA). CAP accredited, ISO 13485 certified, and CLIA certified.

Nateratm is a global leader in cell-free DNA testing, dedicated to oncology, women's health, and organ health. We aim to make personalized genetic testing and diagnostics part of the standard of care to protect health and enable earlier, more targeted interventions that help lead to longer, healthier lives. Natera's tests are validated by more than 100 peer-reviewed publications that demonstrate high accuracy. Natera operates ISO 13485-certified and CAP-accredited laboratories certified under the Clinical Laboratory Improvement Amendments (CLIA) in Austin, Texas and San Carlos, California. For more information, visit www.natera.com.

All statements other than statements of historical facts contained in this press release are forward-looking statements and are not a representation that Natera's plans, estimates, or expectations will be achieved. These forward-looking statements represent Natera's expectations as of the date of this press release, and Natera disclaims any obligation to update the forward-looking statements. These forward-looking statements are subject to known and unknown risks and uncertainties that may cause actual results to differ materially, including with respect to whether the results of clinical or other studies will support the use of our product offerings, the impact of results of such studies, our expectations of the reliability, accuracy and performance of our tests, or of the benefits of our tests and product offerings to patients, providers and payers. Additional risks and uncertainties are discussed in greater detail in "Risk Factors" in Natera's recent filings on Forms 10-K and 10-Q and in other filings Natera makes with the SEC from time to time. These documents are available at www.natera.com/investors and www.sec.gov.

Investor Relations: Mike Brophy, CFO, Natera, Inc., 650-249-9090
Media: Lesley Bogdanow, VP of Communications, Natera, Inc., [email protected]

1. Sparks TN, Norton ME, Flessel M, Goldman S, Currier RJ. Observed rate of down syndrome in twin pregnancies. Obstet Gynecol. 2016;128.
2. Norwitz ER, McNeill G, Kalyan A, et al. Validation of a single nucleotide polymorphism?based non?invasive prenatal test in twin gestations: determination of zygosity, individual fetal sex, and fetal aneuploidy. J Clin Med. 2019;8(7):937.
3. Palomaki GE, Chiu RWK, Pertile MD, et al. International Society for Prenatal Diagnosis Position Statement: cell free (cf)DNA screening for Down syndrome in multiple pregnancies. Prenatal Diagnosis. 2021;41:1222?1232.
4. ACOG Committee on Practice Bulletins?Obstetrics; Committee on Genetics; Society for Maternal-Fetal Medicine. Screening for Fetal Chromosomal Abnormalities: ACOG Practice Bulletin, Number 226. Obstet Gynecol. 2020 Oct;136(4):e48-e69.

SOURCE Natera, Inc.