Abbott launched its updated Oncodetect MRD test on Oct. 26 to monitor traces of cancer during and after treatment. The commercially available blood test uses whole-genome sequencing and technology developed at the Broad Institute of MIT and Harvard. The test looks for circulating tumour DNA, or ctDNA, that can signal residual disease. Detecting those fragments may help doctors assess recurrence risk when cancer is difficult to see on imaging scans.
Abbott acquired Oncodetect through its $21 billion purchase of Exact Sciences, which closed in March. The updated version enters a market that includes Natera’s Signatera, another personalised blood test for residual cancer.
How the Oncodetect MRD test works
Testing begins with tumour tissue obtained during surgery or a biopsy. The laboratory identifies mutations in that tissue, then searches blood samples for matching DNA fragments. This differs from blood-based cancer screening, which looks for possible disease in people without an established diagnosis. Oncodetect monitors patients with known solid tumours. The updated test tracks up to 5,000 patient-specific variants, up from 200. Whole-genome sequencing broadens that search beyond the protein-coding regions examined by the earlier test. Its MAESTRO technology uses molecular probes that bind to selected tumour DNA sequences. It washes away unbound material, concentrating rare cancer signals before sequencing. Broad researchers described the approach in a 2022 publication.
The challenge is separating tiny amounts of tumour DNA from much larger quantities released by other cells. Looking for more mutations gives the assay additional opportunities to identify those scarce fragments. Broad licensed MAESTRO to Exact Sciences in 2023 and worked with the company to develop the commercial test. That collaboration continued after Abbott acquired the business. Tumour sequencing also underpins research into personalised cancer vaccines, although those products serve a different purpose. They aim to stimulate an immune response; the assay measures molecular signs of disease.
Colorectal study shows higher sensitivity.
Abbott presented Beta-CORRECT findings at the European Society for Medical Oncology congress in October. The clinical validation study analysed postoperative samples from 279 patients, predominantly with stage II or III colorectal cancer. Researchers conducted the study at Japan’s National Cancer Centre Hospital East. Eligible disease stages also included surgically removable stage IV cancer.
Abbott reported these results:
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A blood draw approximately one month after surgery identified 72.2% of recurrences within two years, versus 42.2% with the earlier test.
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Among 157 patients tested with both versions, the updated assay detected every positive found by its predecessor, plus 15 additional cases.
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Two-year disease-free survival was 36.2% among patients with detectable postoperative ctDNA, compared with 92.3% among those without detectable ctDNA.
The sensitivity difference was 30 percentage points. These conference findings support recurrence-risk assessment, but do not establish that treatment changes based on testing improve survival. The results also show why a negative result cannot guarantee that cancer will not return. Additional follow-up is expected to clarify relationships between test results, subsequent treatment and recurrence.
Commercial availability and remaining limits
Abbott says the Oncodetect test can detect ctDNA below one part per million under high-input conditions. That laboratory detection threshold is different from the proportion of patients whose recurrence a test identifies. The test requires a healthcare provider’s order. Genomic Health performs it in a laboratory certified under the Clinical Laboratory Improvement Amendments for high-complexity testing.
The Oncodetect MRD test has not been cleared or approved by the FDA. Abbott also cautions that performance may differ in tumour types outside its clinical validation. More than 20 studies are evaluating the updated assay across cancer types, MedTech Dive reported. According to Abbott’s launch announcement, the company is also pursuing broader insurance coverage and international access.
