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July 28, 2023

Natera Announces Completion of Enrollment to the Randomized, Phase III ALTAIR Trial of Signatera™ in Colorectal Cancer

Study to evaluate clinical utility of ctDNA-guided treatment escalation for CRC patients; results expected to read out in mid-2024

Natera, Inc. (NASDAQ: NTRA), a global leader in cell-free DNA testing, today announced the completion of enrollment to the randomized, double-blind phase III ALTAIR clinical trial (JapicCTI-205363/NCT04457297). ALTAIR is the circulating tumor DNA (ctDNA)-guided treatment escalation arm of the CIRCULATE-Japan adaptive trial platform evaluating the utility of the Signatera molecular residual disease (MRD) test in patients with stage II-IV resectable colorectal cancer (CRC). CIRCULATE-Japan also includes the observational GALAXY study and the randomized phase III VEGA trial for ctDNA-guided treatment de-escalation. The company expects to share primary results from ALTAIR in mid-2024.

The ALTAIR investigators have met their goal to enroll >240 patients who tested ctDNA-positive at any time within 2 years after surgery, but with no clinical or radiographic evidence of disease. ctDNA-positive patients are randomized to placebo or TAS-102 (trifluridine/tipiracil), a therapy commonly used for patients with metastatic CRC. The primary endpoint of the study is disease-free survival. ctDNA clearance is a secondary endpoint.

“In this study, we aim to establish the utility of Signatera in the adjuvant and surveillance settings by showing we can improve outcomes for patients with detectable ctDNA before it becomes evident on imaging,” said Dr. Takayuki Yoshino of the National Cancer Center Hospital East, Kashiwa, Chiba, Japan and primary investigator of the CIRCULATE-Japan trial. “Randomized studies such as ALTAIR can help provide compelling evidence to support the use of ctDNA testing as a tool to guide treatment decisions in CRC.”

Completion of enrollment to ALTAIR follows the release of multiple new datasets in 2023 highlighting the clinical utility of Signatera in CRC. In January, the results of >1,000 patients (>7,200 plasma time points) from GALAXY were published in Nature Medicine, demonstrating the ability of Signatera to identify patients with stage II-IV resectable CRC who are at an increased risk of recurrence and to predict who is most likely to benefit from adjuvant chemotherapy. Similar results were reported at the American Society of Clinical Oncology (ASCO) annual meeting in June 2023 with additional data from an expanded cohort of >2,000 patients (>3,800 plasma time points) from the same study.

“The completion of enrollment to ALTAIR marks a significant milestone that will build on recent data from the GALAXY study and bring us one step closer to a future of ctDNA-guided cancer care,” said Dr. Minetta Liu, chief medical officer of oncology at Natera. “We are proud to partner with our collaborators from CIRCULATE-Japan to accelerate precision medicine and transform care for patients with resectable CRC.”

About Signatera

Signatera is a custom-built circulating tumor DNA (ctDNA) test for treatment monitoring and molecular residual disease (MRD) assessment in patients previously diagnosed with cancer. The test is available for both clinical and research use, and has been granted three Breakthrough Device Designations by the FDA for multiple cancer types and indications. The Signatera test is personalized and tumor-informed, providing each individual with a customized blood test tailored to fit the unique signature of clonal mutations found in that individual’s tumor. Signatera is intended to detect and quantify cancer left in the body, at levels down to a single tumor molecule in a tube of blood, to identify recurrence earlier and to help optimize treatment decisions.

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 inform earlier, more targeted interventions that help lead to longer, healthier lives. Natera’s tests are validated by more than 150 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 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 and

Investor Relations: Mike Brophy, CFO, Natera, Inc., 510-826-2350,
Media: Lesley Bogdanow, VP of Corporate Communications, Natera, Inc.,

Source: Natera, Inc.

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