Freeze dried exosomes trialled to treat diabetic foot ulcers
Extracellular vesicles (EVs) including exosomes can provide similar therapeutic benefits to cellular therapy. Rion, a company spun out of the Mayo Clinic in Rochester, Minnesota, recently began phase II trials to evaluate the use of a powdered formulation of platelet-derived exosomes to treat diabetic foot ulcers.
EVs are tiny balls of fat molecules around 100 nm in diameter that contain protein, DNA and RNA from the cell that released them. It is this cargo that provides therapeutic activity. Compared to cellular therapy, EVs have two major advantages. Firstly, they can be freeze-dried to provide stability. Secondly, they do not generate graft-versus-host disease (GVHD) which characterizes cell, tissue and organ transplants. In fact, EVs have the potential to treat GVHD.
Diabetes can impact blood circulation and ulcers can develop in areas where the supply of blood is inadequate. Foot ulcers are a severe, debilitating consequence of diabetes that affects about 20% of diabetics at some point during their lifetime. Of these, 20% will lead to complications that require amputation of the affected foot.
Rion’s trial has focussed on using exosomes derived from blood platelets as these can be readily harvested from donated blood, providing a scalable source of raw material for manufacture. In addition, blood platelets are part of the body’s natural healing mechanism containing many factors that can benefit wound healing.
To ensure sufficient numbers of exosomes can be purified to treat all 40 of the patients in the clinical trial, RION utilized a proprietary purification process. This technology was developed at Mayo’s Van Cleve Cardiac Regenerative Medicine Program and Rion was spun out in 2017.
In addition to diabetic foot ulcers, the company is exploring other indications including, according to the Rion company website, Ev therapies for the skin, heart, muscle, tendon, lung, nerve, and vaginal mucosa.
Rion is not alone in pursuing the therapeutic use of freeze-dried exosomes from primary human cells. For example, researchers at Augusta University are using exosomes derived from adipose mesenchymal stem cells to prevent hypoxia induced muscle injury.
The therapeutic use of EVs is still in its early stages. The EV research community, in particular, will be interested to see what lessons can be learned from these pioneering trials.
IMAGE Conceptual image of an exosome CREDIT Guillaume Pelletier
Learn more about powerful technologies that are enabling research:
