NEW YORK (GenomeWeb) – Bio-Rad Laboratories has received CE-IVD marking on a droplet digital PCR assay to detect BCR-ABL gene fusions. The test can be used to monitor response to treatment in patients with chronic myeloid leukemia and is Bio-Rad's first clinical ddPCR assay to receive a CE mark.
The QXDx BCR-ABL %IS Kit uses ddPCR to provide an absolute measure of BCR-ABL transcripts with high reproducibility, precision, and sensitivity, Bio-Rad said in a statement. The test kit has the benefit of providing absolute quantification, which eliminates the need for standard curves and minimizes variation between samples. It also provides throughput that is scalable from 8 to 48 samples per run, and specificity to detect abnormal transcripts that encode for p210 hybrid BCR-ABL protein associated with CML, but not p190, which is associated with acute lymphoblastic leukemia, the firm said.
Clinicians can treat CML with tyrosine kinase inhibitors, such as imatinib (Gleevex), to reduce the kinase activity of BCR-ABL gene fusions — a translocation of chromosomes 9 and 22 otherwise known as the Philadelphia chromosome. BCR-ABL fusions are typically quantified with mRNA-based methods, but there tends to be variation in measurement between labs as well as challenges as levels get very low, Bio-Rad said.
Digital PCR can overcome these difficulties. For example, a study using Bio-Rad's ddPCR showed a lower limit of detection and quantification than standard qPCR methods, while research published last year using a Fluidigm digital PCR platform showed digital PCR can better detect residual disease than other PCR-based approaches.
The Bio-Rad test will now be available for diagnostic use in Europe, Hong Kong, and New Zealand, and can be run with Bio-Rad's QX200 ddPCR Dx System or AutoDG ddPCR Dx System using the firm's QuantaSoft Software v1.7 for data acquisition and output.
A BCR-ABL test kit from Asuragen received premarket clearance from the US Food and Drug Administration last year, becoming the first such kit commercially available in the US, and the firm has since launched a CE-marked kit to detect minor fusions. A BCR-ABL test from Cepheid was CE marked in late 2015.