Natera Files Signatera MRD Test with FDA

Header - Natera files SIGNATERA test with FDA.   Keynote application is muscle invasive bladder cancer.

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News item assembled by Chat GPT from newswires.  Natera press release here.  Oncodaily here. Urology Times here.

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Natera has submitted a Premarket Approval (PMA) application to the U.S. Food and Drug Administration for its personalized blood test, Signatera CDx, seeking clearance as a companion diagnostic to help guide treatment decisions in patients with muscle-invasive bladder cancer (MIBC) following surgery. 

The company is asking FDA to approve the test for detection of molecular residual disease (MRD) — traces of cancer detectable only at the molecular level — in order to identify which patients are most likely to benefit from adjuvant treatment with the immunotherapy drug Tecentriq (atezolizumab).

The filing is backed by results from the large, randomized phase 3 IMvigor011 trial, which tested whether circulating tumor DNA (ctDNA) detected by Signatera could be used to direct therapy. 

• In that study, patients whose blood tests showed ctDNA — indicating residual cancer after cystectomy — experienced significantly longer disease-free and overall survival when treated with atezolizumab compared with placebo. 
• Conversely, patients who remained ctDNA-negative had a low rate of recurrence without immunotherapy, suggesting many could safely avoid treatment and its potential immune-related side effects. 
• Together, the data support the idea that MRD detection can function as a predictive biomarker, not merely a risk signal, by identifying who is likely to benefit from therapy.

If approved, the test would move MRD detection in bladder cancer from an evidence-supported clinical strategy into an on-label clinical decision tool formally tied to a drug. That would mark a shift toward “recurrence-stage precision oncology,” where treatment decisions are based on molecular evidence of residual disease rather than tumor stage alone. Natera has characterized the application as potentially leading to one of the first FDA-approved MRD blood tests used to guide treatment decisions in a solid tumor setting.

• MRD diagnostic tests have a longer history with blood cancers.  
• See a January 2026 news article in Fierce Biotech about FDA and MRD in myeloma.

Taken together, the PMA submission signals that MRD-guided therapy in MIBC is moving from late-stage clinical research toward potential regulatory reality. The central question now is not whether ctDNA can stratify risk, but whether regulators agree it should be used formally to direct treatment decisions — a decision that could shape the future of MRD testing across many solid tumors.

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Sidebar: Timing 

• The PMA pathway is FDA’s most stringent device review. Although the agency’s formal goal is 180 days after filing, actual timelines vary: straightforward applications may finish in under a year, while more complex ones — particularly In this case, review timing may also be influenced by the drug side of the equation. Because Signatera is being evaluated athose involving novel biomarkers, predictive claims, or companion diagnostic labeling — often take 10–14 months or longer because the review clock stops during sponsor responses. An advisory panel, if convened, can add further delay.
• s a companion diagnostic, its labeling and approval are functionally linked to the clinical context and regulatory status of atezolizumab in this specific bladder cancer setting. Coordination between device and drug review teams is common in such cases, and alignment on indications, patient selection language, and clinical evidence can affect the pace of the process.

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Sidebar:  Tecentriq.  

• Tecentriq (atezolizumab) is a monoclonal antibody that binds PD-L1, blocking its interaction with PD-1 and B7.1 receptors on T cells. This releases an immune “brake,” restoring T-cell–mediated anti-tumor activity so the immune system can attack cancer cells.