High‑sensitivity MRD assay reported
A new assay workflow combines flow cytometry isolation of circulating tumour cells with whole‑genome sequencing to detect minimal residual disease at sensitivities of one tumour cell per million, with reported 100% concordance to bone‑marrow results. The social post described the GenoPredicta approach as highly sensitive and concordant in the reported dataset. (x.com)
Minimal residual disease means cancer cells are still present after treatment, but at levels too low to see on a routine scan or microscope. Predicta Biosciences said its GenoPredicta assay can find those cells in blood or bone marrow at a sensitivity of one tumor cell in one million. (businesswire.com) The workflow starts by sorting rare cancer cells out of a blood sample with flow cytometry, a laser-based cell counter, and then reading the entire tumor genome with whole-genome sequencing. Predicta said the assay can generate results from as few as 50 tumor cells taken from peripheral blood or bone marrow. (businesswire.com) The company reported 100% concordance between peripheral-blood and bone-marrow results in the dataset it cited, and said its analytical validation also showed complete concordance with fluorescence in situ hybridization, the chromosome test commonly used in multiple myeloma. An American Society of Hematology abstract described a retrospective validation set of 68 paired bone-marrow and peripheral-blood samples from 34 patients. (businesswire.com) (ashpublications.org) In multiple myeloma, doctors usually monitor disease with bone-marrow biopsies because the cancer grows in marrow and may not shed enough material into blood for standard liquid-biopsy tests. Predicta’s pitch is that isolating intact circulating tumor cells first, instead of looking only for free-floating tumor DNA fragments, can make blood-based monitoring work at lower disease levels. (predictabiosciences.com) (annalsofoncology.org) That matters because standard minimal residual disease testing in myeloma is already very sensitive, often down to one cancer cell in 100,000 to 1 million bone-marrow cells, but it usually still depends on an invasive marrow sample. A 2022 review in *Clinical Lymphoma, Myeloma & Leukemia* described next-generation sequencing and next-generation flow cytometry as established marrow-based methods at that range. (sciencedirect.com) Whole-genome sequencing also changes what the test can report. Predicta and collaborating researchers said the assay can call copy-number changes, structural variants, and short mutations across the genome, including alterations tied to resistance to B-cell maturation antigen, G protein-coupled receptor family C group 5 member D, and cereblon-directed therapies. (aacrjournals.org) (predictabiosciences.com) The assay is clinically validated in multiple myeloma and other plasma-cell disorders, according to Predicta and Tempus AI, and is being offered to Tempus life-sciences partners for research and clinical-development programs. Predicta launched GenoPredicta as a Clinical Laboratory Improvement Amendments-approved laboratory-developed test in April 2025. (businesswire.com) (biospace.com) The open question is how the blood-based result performs in larger prospective studies and whether it changes treatment decisions or outcomes when used repeatedly over time. For now, the reported result is a company-backed validation and conference-abstract story built around a test designed to make high-sensitivity residual-disease tracking less dependent on bone-marrow biopsies. (ashpublications.org) (businesswire.com)
