NEW YORK – Women's health startup Hera Biotech aims to remove surgical biopsies from endometriosis testing via its minimally invasive MetriDx single-cell endometriosis test.
The San Antonio, Texas-based company recently enrolled the first patient in a proof-of-concept clinical trial and hopes to launch MetriDx as a lab-developed test (LDT) by the end of the year.
MetriDx broadly consists of a uterine brush biopsy followed by single-cell analysis of a 48-gene panel. The company hopes to one day be able to move away from the current gold standard of laparoscopies, surgical procedures used to remove and examine uterine lesions, said Nameer Kirma, Hera's cofounder and chair of the company's scientific advisory board.
"For about 40 to 50 percent of women, it turns out that these lesions are not endometriosis," Kirma said, meaning that many women undergo the procedure unnecessarily.
"That's one of the reasons that doctors delay diagnosis of endometriosis using this procedure," Kirma said, adding that women experience an average delay of approximately seven years to diagnosis.
"That's seven years a woman has to live with a disease without really knowing, [and] with the symptoms [possibly] compounded with other diseases like inflammatory bowel syndrome," Kirma said.
In the MetriDx workflow, endometrial cells are obtained from the brush biopsy and fed to a C1 instrument from Standard BioTools (formerly Fluidigm) and loaded on 96-well microfluidic chips, where cDNA is obtained and amplified, before being transferred to a Biomark tool, also from Standard BioTools, for qPCR and analysis of gene expression values.
"One of the interesting things about single-cell analysis," Kirma mentioned, "is that we can actually separate the endometrial tissue we get from the biopsy into two major cell types … epithelial and stromal cells."
Kirma explained that this effectively increases the number of data points that Hera can get from the tissue because the two cell types express the panel's genes differently.
"If we just do a pool of the two cell types, then these differences will be averaged out and we won’t detect specific differences in pattern," he said.
In attempting to design a minimally invasive alternative to diagnosing endometriosis, Hera joins a fairly small playing field, but one in which each player has adopted a very different approach.
San Diego-based Xosomix ("exosomics") and Oakland, California-based NextGen Jane both sample menstrual effluent, but for very different biomarkers. Xosomix uses multiplexed quantitative proteomics to identify endometriosis-associated proteins, while NextGen Jane looks for endometrial tissue-associated RNA markers of endometriosis. Meanwhile, Innovative Health and AIMA Labs are working together on a test that assays microRNA found in blood.
NextGen Jane is developing a tampon-style device to collect menstrual effluent during the natural shedding of uterine lining during menstruation.
"This provides multiple advantages over clinic-based sampling methods, whether biopsy or surgery," said CEO Ridhi Tariyal. "Our sample collection kit can be used at home, mailed in without cold chain, and provides enough high-fidelity material to power multiple sequencing pipelines."
This convenient and simple sample collection, she said, should lower patient engagement barriers and enable repeat, longitudinal sampling to track disease state and treatment efficacy over time.
Tariyal added that from a scientific perspective, the cell type diversity found within the menstrual milieu facilitates immunological research into endometrial disease.
"Not only do we collect cell types found in an endometrial biopsy," she said, "but we also collect key innate immune cell populations and microbial cells not found in a biopsy. The interaction of these diverse cell types is key to assessing uterine pathologies."
Tariyal said that NextGen Jane chose to pursue RNA-based diagnostic methods due mainly to the sizeable volume and diversity of RNA species that can be sequenced at low cost, and because RNA-based biomarkers are easily adapted to other indications and therefore to other products, beyond a one-off endometriosis test. The company views this approach as a viable way to build diagnostic and therapeutic applications for multiple female-specific disease states.
Pranav Sharma, cofounder and CSO of Xosomix, said that while his company is also looking at RNA, due to the important regulatory roles it plays in endometriosis, Xosomix sees protein-based assays as a more dynamic means of measuring a disease state rapidly and over time.
"Proteins are real-time indicators of cell state and health," he said, while commenting that RNA is "several degrees removed from real-time status indication."
Hera's Kirma cautioned, however, that proteins risk being nonspecific with respect to endometriosis itself, as opposed to inflammation more generally. Even blood tests for mRNA, he said, can suffer from a lack of specificity.
"MetriDx is going after the source tissue which causes the disease," he said, adding that its strength also comes from the evidence that the genes Hera has chosen for its panel are involved in actually causing the disease.
Hera's current clinical trial aims to prospectively evaluate MetriDx's diagnostic accuracy among 60 participants. The company also plans to use the data generated from these patients to develop machine learning algorithms that can better predict endometriosis. Hera Biotech recently raised $2 million in seed funding, which it is using to complete this trial.
Although Hera plans to launch MetriDx as an LDT by the end of the year, the company also plans to seek breakthrough device designation from the US Food and Drug Administration this year, in hopes of eventually obtaining regulatory approval.
Although the company sees potential in developing future tests for disorders that can be confounded with endometriosis, there are no concrete plans to do so at this point.