Technology company Tempus has announced the launch of the new minimal residual disease (MRD) assay, xM, designed for colorectal cancer (CRC) research.

The xM assay is a tumour-naïve, plasma-based test that detects circulating tumour DNA (ctDNA) in blood samples from patients with early-stage CRC following surgery.

Currently available for research use only, the xM assay represents a liquid biopsy approach to MRD assessment that does not require baseline tumor tissue. It provides a binary MRD result using both methylation and genomic variant classifiers.

The assay incorporates algorithms to filter out artifacts, CHIP and germline variants.

The goal of xM is to identify and monitor patients with low levels of ctDNA who may be at risk of recurrence, potentially guiding more aggressive or post-surgical treatments.

Tempus chief scientific officer Kate Sasser said: “Colorectal cancer is the second leading cause of cancer-related deaths worldwide, and surgical intervention alone may not be curative for all patients. Emerging data suggests that patients may benefit from diagnostic tests that can detect recurrence with more analytical sensitivity compared to standard surveillance mechanisms like imaging.

“We are excited to introduce a blood-based MRD test that can quickly assess if a patient is at risk of recurrence with high specificity and sensitivity, and xM is a great complement to our growing portfolio of diagnostics as it is a very helpful tool for patients earlier in their treatment journey.”

Tempus is also conducting additional clinical validation studies to potentially enhance these performance metrics.

With the addition of xM to its product suite, Tempus now offers two distinct MRD assays.

The company's portfolio also includes the tumour-informed test NeXT.

In November 2023, Tempus introduced the new ctDNA assay, xF Monitor, to be used for research purposes only.