A new study has demonstrated the ability of the Signatera test from Natera, San Carlos, Calif, to assess the response of metastatic cancer patients to immunotherapy, across multiple cancer types, by detecting molecular traces of circulating tumor DNA (ctDNA) in the blood.1
Conducted at the Princess Margaret Cancer Center, Toronto, the study enrolled 70 patients with advanced cancer, including head and neck, triple-negative breast, melanoma, and ovarian cancers. Patients were treated with the single-agent immune checkpoint inhibitor pembrolizumab as part of the Phase II Inspire trial. The study used Signatera to assess ctDNA at baseline and again at the start of the third treatment cycle.


Alexey Aleshin, MD, PhD, Natera.

Results showed a strong correlation between changes in ctDNA and overall survival (adjusted HR = 0.38; p = 0.004), progression-free survival (adjusted HR = 0.47; p = 0.006), and overall clinical response rate, illustrating that ctDNA may be a valuable predictive biomarker for patients with mixed solid tumors treated with checkpoint inhibitors. Signatera, a personalized, tumor-informed blood test, detected ctDNA in 68 out of 70 patients at baseline (97% sensitivity).

“This study is another strong indication of Signatera’s potential to impact the management of cancer, following several other studies recently published in key peer-reviewed journals,” says Alexey Aleshin, MD, MBA, oncology medical director at Natera. “This growing body of evidence highlights the promise of our technology to help physicians and researchers detect molecular residual disease, measure treatment response, and identify recurrence earlier than the standard of care in patients with a variety of cancers.”

Signaterais a custom-built ctDNA test for treatment monitoring and molecular residual disease assessment in patients previously diagnosed with cancer. The test is available for clinical and research use. The Signatera methodology 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 tissue.

Such personalization maximizes accuracy for detecting the presence or absence of disease in a blood sample, even at levels down to a single tumor molecule in a tube of blood. Unlike a standard liquid biopsy, Signatera is not intended to match patients with any particular therapy; rather it is intended to detect and quantify how much cancer is left in the body, in order to improve prognosis and help optimize treatment decisions.

For further information, visit Natera.


  1. Iafolla MAJ, Yang C, Dashner S, et al. Bespoke circulating tumor DNA (ctDNA) analysis as a predictive biomarker in solid tumor patients (pts) treated with single agent pembrolizumab (P) [abstract 2542]. Presentation at the annual meeting of the American Society of Clinical Oncology, Chicago, May 31–June 4, 2019. J Clin Oncol. 2019;37(15 suppl):2542; doi: 10.1200/jco.2019.37.15_suppl.2542.