GentiBio Joins Cell Therapy Chase With $20M and New Treg Technology

One of the challenges facing cell therapy developers is collecting enough cells to produce a viable treatment. It’s a particularly pronounced problem for therapies employing regulatory T cells (Tregs), a type of immune cell that’s relatively scarce in the blood, says GentiBio CEO Adel Nada.

Some biotech companies are developing Treg cell therapies from a patient’s own Tregs. GentiBio makes its Treg therapeutic candidates from an entirely different type of immune cell, and Nada says this approach could make Treg cell therapy production more scalable. On Wednesday, the Boston-based startup announced its launch backed by $20 million in funding.

The immune system is comprised of many different types of cells that have different functions. For example, T cells seek out and destroy pathogens, and they also prompt other immune cells to mount a response. Tregs do the opposite, regulating or suppressing an excessive immune response. Such overreactions are associated with some autoimmune disorders, making Treg cell therapies promising as a way to treat them.

Rather than harvesting a patient’s Tregs, engineering those cells, and then multiplying them in a lab, GentiBio works with immune cells called CD4+, which are also known as “helper T cells.” In addition to playing multiple roles in an immune response, these cells are abundant in the blood. GentiBio uses genetic engineering techniques to make Treg-like cells from CD4+ cells. Scientists have already shown that this approach can work in animals. Not only has the technology produced these engineered Tregs, but these cells have also shown the potential to address graft-versus-host disease and encephalitis in mice. Results were published in June in the journal Science Translational Medicine.

GentiBio’s Tregs are engineered with additional features. Attaching a T-cell receptor to these cells enables them to target specific tissues, Nada says. He adds that synthetic biology technology helps these cells survive longer than typical Tregs. Once infused into a patient, these cells would be “tunable,” meaning that their numbers could be dialed up or down to the level needed to treat a particular disease. Nada declined to disclose his company’s disease targets, other than to say that they are “autoimmune diseases of high unmet medical need.”

A growing number of companies are researching Treg therapies as a way to treat various diseases. Sonoma Biotherapeutics launched in February, revealing $40 million in Series A financing and its plans to engineer cell therapies from a patient’s own Tregs. The startup, which splits its operations between South San Francisco and Seattle, has not disclosed its disease targets but co-founder and CEO Jeffrey Bluestone told Xconomy that in addition to autoimmune disorders, the company’s approach has potential applications in treating cancer and neurodegeneration.

Pandion Therapeutics (NASDAQ: [[ticker:PAND]]) is developing drugs intended to treat disease by multiplying Tregs throughout the body without activating inflammatory cells. Last month, the Watertown, MA-based biotech’s IPO raised $135 million, part of which will support PT101, the company’s lead drug candidate that is currently in early-stage testing in moderate-to-severe ulcerative colitis. San Francisco-based Orca Biosciences is developing proprietary “mixtures” of various types of immune cells, including Tregs, to address disease. One of its programs, a combination of T cells and Tregs, is currently in Phase 1/2 testing in blood cancers.

GentiBio’s approach can be used to make Treg therapies from a patient’s own cells, as well as “off-the-shelf” therapies produced from the cells of healthy donors. Nada says it’s too early to talk about which type the company is developing. The company’s research is based on technologies licensed from Seattle Children’s Hospital and Research Institute, the Virginia Mason Health System-affiliated Benaroya Research Institute in Seattle, and Israel’s MIGAL Galilee Research Institute.

“With the academic collaborators we’ve been working with, we’ve generated preclinical data that can support regulatory filings [for clinical trials],” Nada says. “We have assets that allow us to steadfastly march to the clinic, at a pace that is not what you would expect from an academically grown asset.”

GentiBio’s financing, a seed round, was led by OrbiMed, Novartis Venture Fund, and RA Capital Management. Nada says the new cash enables his company to build infrastructure, including manufacturing, to support early-phase clinical testing in two indications, as well as non-clinical research for its other programs. GentiBio will need to raise more money next year to support those additional programs, Nada says.

Photo by Flickr user Alachua County via a Creative Commons license