NEW YORK – Genetron Health is anticipating significant milestones for its solid tumor minimal residual disease (MRD) technology this year, buoyed by new data highlighted in Clinical and Translational Medicine and presented at the recent annual meeting of the American Association for Cancer Research.
In a letter, company researchers described their comparison of different approaches for residual disease detection in a small cohort of patients with hepatocellular carcinoma — the firm's first MRD target market.
According to the company, recurrence is the major reason for mortality after hepatectomy or liver transplantation surgery for HCC, and MRD detection stands to help oncologists better direct their post-operative plans for patients.
In the study, investigators analyzed multiple potential MRD biomarkers: circulating tumor cells (CTCs), as well as three distinct circulating tumor DNA (ctDNA)-based approaches. These included a purely tumor-agnostic fixed panel assay, a universal fixed panel designed to target frequently mutated regions in HCC as well as the hepatitis B virus, and a tumor exome-informed, fully personalized assay strategy, akin to products like Natera's Signatera.
In samples from 66 patients, the group found that the tumor-informed methodology provided the best prediction of HCC recurrence, although the universal panel was also strongly predictive in a subset of patients with panel mutations detected in their tumor. The tumor-naive fixed panel performed more poorly, but its power was improved when it was combined with CTC detection.
During a call with investors this week discussing the firm's Q1 financial results, Genetron CEO Sizhen Wang reiterated that Genetron continues to plan to provide two MRD assays in the HCC space: a next-generation sequencing-based, tumor-informed approach, as well as a fixed-panel PCR assay that would provide self-pay patients with a less expensive solution.
Evidence from the new study provides an early hint at how that might shake out, with CTCs providing a sensitivity boost to a tumor-naive panel.
Wang also said the company continues to plan to eventually offer MRD testing in a pan-cancer setting under an assay codevelopment project with AstraZeneca. The firm is planning a pilot launch before the end of June, with broader availability planned for the end of this year when assay optimization is expected to complete.
This pan-cancer product is being developed using the same Mutation Capsule technology at the heart of the company's tumor-informed HCC approach, featured in the new CTM study.
According to Wang, Mutation Capsule allows highly sensitive detection in low-yield cell-free (cfDNA) samples with higher conversion efficiency of cfDNA molecules. This in turn enables multiple test analyses using a single cfDNA sample, allowing the type of head-to-head comparisons investigators reported.
The new HCC publication joins previous retrospective data in colorectal cancer — showing over 91 percent sensitivity and 95 percent specificity — and in gastric cancer, where the personalized MRD approach could detect tumor DNA at 0.001 allele frequency in peritoneal lavage fluid samples.
"Currently, there are only a handful of companies in China that may have the capability to develop a high-perform[ing] MRD assay," Wang said, adding that upon the completion of its validation work with AstraZeneca, Genetron's assay will be used exclusively by the pharma firm for its China-specific trials.
Beyond that first layer of collaboration, Wang said it's likely that the companies will also work together to promote the assay in a clinical setting, though those details are still being discussed.
"Both sides are excited that we will be able to codevelop this assay with the technology from Genetron and samples and data from [AstraZeneca] plus the investment from both sides, and we see quite a bright future to incorporate this … in both the clinical trials as well as to serve the patients in the clinical setting," he said.
One of Genetron's main competitors, Burning Rock Biotech, has already launched its own MRD offering, saying this week that although the product has only been on the market since March, uptake has been encouraging, as Chinese oncologists have begun to embrace the potential utility of solid tumor MRD.