NEW YORK – Beverly, Massachusetts-based startup TellBio aims to use its circulating tumor cell, or CTC, collection technology for early detection of tumor progression and to develop therapeutics based on CTC biomarkers.
Earlier this month, the company inked a collaboration with ARUP Laboratories, based in Salt Lake City, which expects to use TellBio's platform for several research programs in solid tumor types, including prostate and gynecological cancers. It also raised $5 million in a Series A financing round and licensed its TellDx diagnostic platform exclusively to Genetron for development in China.
TellBio, cofounded in 2019 by Richard Peters and Massachusetts General Hospital researchers Daniel Haber, Mehmet Toner, David Ting, Shyamala Maheswaran, and Ravi Kapur, is commercializing a sample prep technology called CTC-iChip, which they described in a publication in 2013. The platform uses high-throughput microfluidics to deplete hematopoietic cells from blood samples.
CTC-iChip initially performs size-based separation of nucleated cells from red blood cells, platelets, and plasma, followed by the removal of white blood cells, or WBCs, tagged with magnetic bead-conjugated antibodies, including CD45, CD16, and CD66b. The rest of the mixture then contains CTCs as well as any remaining WBCs.
Licensing the CTC isolation approach from MGH, TellBio built a diagnostic platform called TellDx and is now developing a complementary therapeutic platform that the firm has branded as "TellRx." TellBio is partnering with academic centers like MGH and ARUP to apply TellDx — which combines CTC-iChip and an automated benchtop processor called CTC Isolator II — in the research space.
While the cofounders have previously combined CTC-iChip with downstream detection methods in hepatocellular carcinoma and breast cancer, TellBio CEO Pritesh Gandhi said that the firm has used TellDx for research applications in other cancers: allele-specific PCR amplification and EGFR mutational analysis in lung cancer; real-time PCR and western blot analyses in melanoma; and immunofluorescence and cell imaging in prostate cancer.
Gandhi said that prior to the COVID-19 pandemic, TellBio also decided to investigate developing cancer therapies because it sees synergy between targeted diagnostics and therapeutics using the CTC purification platform.
Highlighting that the TellDx platform is cancer-agnostic, Gandhi said the firm will look at a "variety of different targets," which remain undisclosed, as it interrogates CTCs and characterizes their proteomes and genomes. The firm expects to analyze emerging preclinical data to prioritize CTC targets for the TellRx platform, with the goal to prevent cancer metastasis.
"One of the advantages [of TellDx] is that you're capturing viable cells, and you can get a lot of information from those cells, both genomic and proteomic," he added.
TellDx, which Gandhi noted requires 10 mL of a patient's blood, can isolate CTCs within three hours prior to downstream detection methods such as PCR and sequencing.
The firm has raised a total of about $6.5 million between its recent Series A round and initial seed funding, Gandhi said.
Adam Barker, director of ARUP's Institute for Clinical and Experimental Pathology, said that his team first began discussions with TellBio in late 2020. Acknowledging that the partnership is ARUP's "first foray" into the liquid biopsy space, Barker said that medical directors at the Huntsman Cancer Institute and the University of Utah have contacted him and expressed interest in the TellDx system, especially for prostate-cancer related research.
Researchers at his institution already perform single-cell sequencing and plan proteomics studies of cancer cells, Barker explained. "We also have an [artificial intelligence] connection with a company we work [with] who wants to work with the CTC assay and say 'hey, do they look different, and can we make a call based [on] their morphology and where they came from?'"
He added that some researchers also want to count the number of live CTCs that a patient may have pre- and post-treatment, as well as establish the long-term implications of different drugs.
"We know that [prostate cancer patients] have CTCs, and we will collect their CTCs to see what their baseline count is," Barker said. "The next step is, now [that] they've [gone] through treatment, to see what the CTC levels look like."
Barker said that TellBio also wanted to work with his team because of ARUP's ability to potentially shorten the time for sample collection across the US. ARUP anticipates sequencing DNA from extracted CTCs using Illumina's TruSight Oncology assay.
In addition to prostate cancer, Barker noted that he and his colleagues may branch out to study melanoma, cervical cancer, and other gynecological cancers using the TellDx platform.
While TellBio is currently in early discussions with the US Food and Drug Administration to determine the appropriate commercial pathway for the TellDx platform for diagnostic applications, Gandhi expects the firm to initially ramp up its supply of the CTC collection devices and explore their use in cancer research at further institutions in the US and around the world.
TellBio anticipates TellDx's use in the hospital and commercial laboratory setting as a noninvasive option to measure progression of a patient's tumor prior to other clinical methods like radiology imaging.
In addition to being cancer-agnostic, Gandhi said, TellBio's system stands out from other microfluidic methods that isolate CTCs because it collects live cells instead of dead cells. He pointed out that TellBio is already generating revenue because it has deployed TellDx in research labs and will "leverage that revenue to finance our [synergistic] therapeutics piece."
While acknowledging that ARUP has used microfluidic products that search for CTCs, Barker believes TellBio's system is "unique" because of its unbiased cell collection. He said that other assays typically isolate CTCs using immunoassays that require specific antibodies.
"Instead of pulling the needle away from the haystack, [TellBio] is pulling the haystack from the needle," Barker explained. "You don't need to know anything about the CTCs, [as] the actual mechanical way [allows you] to separate them by size."
Gandhi noted that TellBio, following its licensing and distribution agreement with Genetron in China this month, will continue to look at international markets and deploy a research-use-only prototype version of TellDx internationally later this year. The firm plans to eventually seek a CE mark for the platform, as well.