PHILADELPHIA—As ArunA Biomedical CEO Mark Sirgo tells it, his colleague Steve Stice, Ph.D., had been “throwing away the best part for years.”
He’s referring to exosomes, a cellular component long thought of as the cell’s garbage removal system. But companies are looking at the exosome in a new light. ArunA is working on developing exosomes for use as a drug delivery vehicle, as well as a treatment in their own right.
ArunA started out as a reagent company, licensing stem cell technology from Stice’s lab back in 2005. It manufactured stem cells for researchers both in academia and industry before pivoting to exosomes in 2016.
Exosomes do get rid of waste, but that’s just one facet of their job. It fits under the greater umbrella of sending messages between cells, said Stice, ArunA’s chief scientific officer and co-founder.
“We equate them to carrier pigeons. Inside are proteins and RNA … They used to be thought as a way to get rid of waste, packaging it in a lipid bilayer and throwing it out the door,” he said. “In fact, it’s not that at all—they carry these messages from one cell to another, transmitting those proteins and RNAs to other cells in the body.”
Exosomes are also “decorated” on their surface with proteins and sugars—“things that will get them across different barriers,” Stice said. That includes the blood-brain barrier, ArunA's primary interest. But that's not all: The company has found exosomes without a drug payload can have a therapeutic effect, too.
Athens, Georgia-based ArunA is looking to use exosomes to treat diseases of the central nervous system (CNS): “We’re looking to hijack this natural process in which neural cells communicate, particularly at the time of an injury,” Stice said. One use case would be amyotrophic lateral sclerosis (ALS), in which exosomes might be used to provide degenerating nerve cells with the “message” to regenerate, he said.
The company is starting with stroke because of the limitations of treatments—the clot-busting drug tPA must be administered as quickly as possible, and procedures to physically remove a blood clot from the brain only work for certain types of strokes.
ArunA has tested its stroke treatment in pigs, finding that its exosome treatment preserved brain tissue in pigs that survived a stroke. Treated animals were walking better than untreated animals three days after a stroke, Stice said. The candidate, dubbed AB126, “eliminates that conversion to what we call a hemorrhagic stroke, or bleeding of the brain, preserving tissue,” he said.
The company aims to push the program into the clinic in 2021. But it doesn’t want to get pinned down as a stroke company.
“Our work in stroke illuminates [the technology’s] applications in other things,” Sirgo said. The company plans to apply these lessons in neurodegenerative diseases such as ALS, Alzheimer’s and Parkinson’s. This CNS focus separates it from Codiak, the exosome player that’s “out in front” working in immuno-oncology, Sirgo said.
Another differentiating factor is the company’s past life as a reagent company. Manufacturing exosomes can be a variable process, but ArunA’s experience making large amounts of stem cells has helped it produce exosomes consistently.
ArunA has its pre-IND meeting with the FDA early next year, and if all goes to plan it will file the IND for AB126 in the second half of 2021.
“We definitely want a financing between now and then,” Sirgo said.
Though the company has a clear goal of creating its own CNS pipeline, it hasn’t ruled out partnerships with other companies that may want a way to get their own compounds across the blood-brain barrier.