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April 1, 2022

Natera Announces Publication Highlighting Importance of Testing Total cfDNA when Monitoring Kidney Transplant Patients with COVID-19 Infection

AUSTIN, Texas, April 1, 2022 /PRNewswire/ — Natera, Inc. (NASDAQ: NTRA), a global leader in cell-free DNA (cfDNA) testing, announced the results of a study1 to examine both total and donor-derived cell-free DNA (dd-cfDNA) in kidney transplant recipients hospitalized with COVID-19 using its Prospera™ test to assess disease severity and risk of rejection.

The study, published in Transplantation Proceedings, used the Prospera test to examine the relationship between total cfDNA and dd-cfDNA fraction when monitoring for rejection. The results indicate that high levels of total cfDNA, as can occur due to COVID-19 infection, result in a lower dd-cfDNA donor fraction and could inadvertently mask rejection when using donor fraction alone. The Prospera test identified two patients in the cohort with elevated total cfDNA and biopsy-proven rejection that would have otherwise gone undetected by dd-cfDNA donor fraction alone.

"COVID-19 has presented unique challenges in monitoring and treating kidney transplant recipients and it’s clear that infection is one of the many factors that can impact cfDNA levels – and therefore a dd-cfDNA fraction," said José Otto Reusing Jr., principal investigator and lead author of the study, at the University of São Paulo School of Medicine in Brazil. "The ability to test total cfDNA with Prospera is critical to establishing a more complete and thorough understanding of graft health with these patients."

Natera incorporated total cfDNA into the Prospera test in 2021, based on previous studies2-4 that showed combining analysis of dd-cfDNA and total cfDNA improved performance when evaluating transplant rejection.

About the Prospera test

The Prospera test leverages Natera’s core single-nucleotide (SNP)-based massively multiplexed PCR (mmPCR) technology to identify allograft rejection non-invasively and with high precision and accuracy, without the need for prior donor or recipient genotyping. The test works by measuring the fraction of donor-derived cell-free DNA (dd-cfDNA,) and the total cfDNA in the recipient’s blood. It may be used by physicians considering the diagnosis of active rejection, helping to rule in or out this condition when evaluating the need for diagnostic testing or the results of an invasive biopsy. The Prospera test has been clinically and analytically validated for performance regardless of donor relatedness, rejection type, and clinical presentation. It 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.

About Natera

Natera™ 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

Forward-Looking Statements

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 our efforts to develop and commercialize new product offerings, our ability to successfully increase demand for and grow revenues for our product offerings, whether the results of clinical or other studies will support the use of our product offerings, our expectations of the reliability, accuracy and performance of our screening tests, or of the benefits of our screening 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 and


Investor Relations: Mike Brophy, CFO, Natera, Inc., 510-826-2350
Media: Kate Stabrawa, Communications, Natera, Inc., 720-318-4080

  1. Reusing Jr JO, Yoo J, Desai A, et al. Association between total cell free DNA and SARS-CoV-2 in Kidney Transplant Patients: A Preliminary Study. Transplant. Proc. 2022. ISSN 0041-1345.
  2. Halloran, et al. Manuscript in preparation, anticipated publication in 2022.
  3. Bunnapradist S, Homkrailas P, Ahmed E, Fehringer G, Billings PR, Tabriziani H. Using both Fraction and Quantity of Donor-Derived Cell-Free DNA to Detect Kidney Allograft Rejection. J Am Soc Nephrol. 2021;32(10):2439-2441.
  4. Bunnapradist S, Datta N, Schaenman J, et al. Extremely High Cell-free DNA Levels Observed in Renal Allograft Patient With SARS-CoV-2 Infection. Transplant Direct. 2021;7(5):e691.


SOURCE Natera, Inc.

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