A new study demonstrates the ability of Natera's Signatera test to assess patient response to immunotherapy in the metastatic setting across multiple cancer types by detecting molecular traces of circulating tumor DNA (ctDNA) in the blood.
The study, conducted by Princess Margaret Cancer Centre in Toronto, 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 (NCT02644396). The study used Signatera to assess ctDNA at baseline and again at the start of the third treatment cycle.
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 percent sensitivity).
Across clinical studies in breast, bladder, colorectal, and non-small cell lung cancers, Natera has demonstrated the ability to detect molecular residual disease up to two years earlier than radiographic imaging. Results also have shown that a positive Signatera result without further treatment has predicted clinical relapse over 98 percent of the time.