NEW YORK – NeoGenomics has taken new steps in building evidence to establish its blood-based cancer detection assay in the early-stage breast cancer space.
Investigators presented two studies at the San Antonio Breast Cancer Symposium last week showing that the firm's molecular residual disease test could detect lingering or reemerging tumor DNA in patients' blood across a variety of timepoints and cancer subtypes.
NeoGenomics' platform, called Radar, falls under the umbrella of minimal residual disease or molecular residual disease (MRD) testing and is akin to certain competing assays on the market, namely Natera's Signatera, which has been adopted in the setting of colorectal cancer. The Radar technology, a tumor tissue-informed, patient-specific sequencing method, was developed initially by Inivata, which NeoGenomics acquired in 2021.
Each Radar assay is a personalized panel of up to 48 variants that are selected for each patient based on upfront tumor sequencing data. The 48 variants are then gauged via sequencing in cell-free DNA extracted from the patient's blood sample.
Several MRD products have already launched commercially for detecting residual colorectal cancer, and Medicare contractor Palmetto GBA has established a so-called "foundational" local coverage determination (LCD), which grants reimbursement to labs performing blood-based colorectal cancer screening tests that pass the MolDX program's technical assessment process.
While the company has faced some hurdles this year in gaining recognition under the Palmetto colorectal cancer LCD, NeoGenomics plans to advance Radar across multiple tumor types. The company is conducting research in head and neck as well as lung cancers, and according to Vishal Sikri, president and chief commercial officer of the Inivata subsidiary, breast cancer may be where it can demonstrate the most added value over competing platforms.
"The reality is that colorectal [cancer] is where the initial application is," Sikri said in an interview. "We believe that Radar still has a place in the colorectal [cancer] side of things but, combining it all together and looking at these applications across multiple cancer types is [our larger goal]."
In the breast cancer space, where MRD assays need to be sensitive enough to pick up the presence of mutant alleles at low levels, Radar has a chance to differentiate itself, Sikri believes. "Especially when you are seeing mutant allelic fractions that are below 0.1 percent, that's really where I would say the value of Radar shines," he said. "Breast cancer is a good place for us to be just because of the high sensitivity and specificity of the technology itself."
According to Sikri, the data NeoGenomics shared at SABCS add weight to other evidence that Radar can detect either residual cancer signal or cancer reemergence across the neoadjuvant, adjuvant, and surveillance settings.
"When we look at some of our earlier breast [cancer] data, a lot of it was pilot data. … And with these two studies, we're seeing two cohorts with nice mature follow-up," added Amber Carter, NeoGenomics' VP of clinical programs.
Of particular note, in the c-TRAK TN trial, researchers compared the company's Radar results to a digital PCR approach, offering a rare take on cross-assay concordance in a field where head-to-head comparisons have been relatively few and far between. "What's really nice about [this] is that it really highlights the value of the sensitivity around the Radar assay compared to what is typically done … or is planned to be used from some of our competition," Sikri said.
Analyzing patient data in the surveillance setting over a median follow-up of about 22 months, investigators reported that Radar detected ctDNA in nearly 40 percent of the 141-patient cohort, compared to about 36 percent for dPCR. Eight patients were deemed positive for a cancer signal by Radar but not by dPCR, and two by dPCR but not Radar. Five of the eight dPCR negatives went on to relapse, as did one of the Radar negatives.
The researchers wrote that Radar offered the first hint of recurrence for nearly half of the patients who showed a molecular recurrence in the form of emerging circulating tumor DNA. In the remaining half, both assays registered positivity at the same timepoint.
They added that Radar also boasted a longer time between ctDNA detection and relapse than dPCR — a median of 6.1 months versus 3.3 months, respectively.
"It's nice to have access to this good-sized cohort from an important clinical trial that also has an orthogonal method attached to it … [and] to have enough sample to run two different assays is really, really rare, so we're very pleased with the results," Carter said.
The data show that both assays can detect recurrence, but Radar did it sooner, Carter added, highlighting that the take home message is that "there are more sensitive assays and less sensitive assays, and these sorts of considerations are important when planning clinical trials or choosing a test."
In a second presentation, investigators reported preliminary data from a long-term prospective cohort study called TRACER, which is investigating the use of Radar in patients with early breast cancer across multiple subtypes. Samples were measured at baseline, during neoadjuvant chemotherapy, surgery, and at post-surgical follow-up.
Among 98 of the first subjects enrolled, Radar was able to detect circulating tumor DNA in 80 percent at baseline — prior to neoadjuvant chemotherapy — allowing for further monitoring of ctDNA dynamics during treatment and post-surgery.
"There's so much to be mined from the TRACER data," Carter said. "We have 104 patients so far on the poster, but there are more patients coming."
There are certain questions the team already wants to focus on moving forward, including gaining a better understanding of clinical sensitivity from certain timepoints and ctDNA dynamics. But in a study like TRACER, "there's also the ability … to just look and see what else the data tells us," she added.
For example, one of the highlights presented at the meeting was that early-stage estrogen receptor-positive breast cancers that didn't clear ctDNA after neoadjuvant therapy appeared to have a higher risk of recurrence.
NeoGenomics recently stated its intent to focus its near-term investment and effort on offering Radar in the breast cancer space, citing an accelerated commercial launch target for Q1 2023.
Unlike colorectal cancer, where there is the foundational LCD already in place for molecular MRD tests, Inivata would have to start from scratch in pursuing a coverage determination from Medicare when Radar is performed for breast cancer patients.
"This is where it's on us to help establish what that looks like in breast cancer, through current data, data we need to build, and areas within breast cancer where we need to get more granular … so that we can show that it's clinically useful and make the case to payors," Carter said.
According to Sikri, NeoGenomics and Inivata are "helping set the trend" with their existing breast cancer data and new analyses like the two SABCS reports. "We feel confident that we have a path forward to where we need to go," he said.
Sikri and Carter also argued that the clinical milieu of breast cancer — the patient and physician community and how they interact — is different than the clinical care environment for other tumors such as colorectal cancer. Precision medicine has a long history in early breast cancer, and patient advocacy is robust, and this may help with test adoption.
Also, while MRD testing in colorectal cancer is mainly the purview of oncologists, in breast cancer, "surgeons are really interested in what's happening in the space and how they can also play a role, especially in the neoadjuvant setting," Sikri added.