Stem cell company conducts research on innovative ABCB5+ mesenchymal stromal cells (MSCs) in collaboration with leading scientists

Main image: Figure 1: Drug development based on ABCB5+ mesenchymal stem cells.

For nearly 20 years, the biopharmaceutical company RHEACELL has been dedicated to researching and clinically developing innovative stem cell therapies. The focus is on severe immune and inflammation-related diseases with a high unmet medical need. Clinical trial programs are being set up with leading international experts in order to develop the RHEACELL therapeutics to market maturity based on the innovative approach of the MSCs. With two Phase III approval studies currently underway, a breakthrough in this new form of regenerative medicine could soon be imminent. 

Due to their anti-inflammatory potential and unique immunomodulating property, ABCB5+ mesenchymal stem cells (MSCs) are considered a pioneering therapeutic approach in regenerative medicine. The focus is on chronic inflammatory diseases, such as the rare disease epidermolysis bullosa – also known as butterfly disease – and non-healing chronic wounds (e.g.  chronic venous ulcers, CVU). These stem cells target the underlying inflammation while promoting wound healing by restoring normal physiological function to the affected tissue.

Basic research into the causes of chronic wounds in various inflammatory diseases and the regenerative potential of ABCB5+ MSCs has been conducted for many years in close cooperation with leading scientists in this field. A successful example is the research partnership with the University of Ulm, led by scientist Professor Dr. med. Karin Scharffetter-Kochanek, Director of the Clinic for Dermatology and Allergology. Together with RHEACELL, they received the "Science-Economy cooperation award” in 2022. The scientific team led not only characterized the detailed mode of action of mesenchymal stem cells derived from the skin and identified their special regenerative potential, but also successfully transferred these findings into clinical development.

"Our successful cooperation began more than 10 years ago through a chance meeting on a train ride to a conference for dermatologists. Our vision back then, to develop a cell-based therapeutic agent using mesenchymal stem cells to treat people with inflammatory, degenerative diseases and the resulting chronic wounds, immediately caught the interest of Professor Scharffetter-Kochanek", explains Dr. med. Christoph Ganss, physician, co-founder and managing director of RHEACELL.

Professor Scharffetter-Kochanek’s team discovered that ABCB5+ MSCs have remarkable regenerative potential and can "calm" overactive phagocytes (macrophages), which play a key role in chronic inflammation.

"This stem cell fascinates us deeply. We have learned so much about them from the first cell cultures to the preclinical models. For me, this joint research is a highlight, because it means a lot for the treatment of chronic wounds in medicine and for dermatology. Given the high unmet medical need for treating non-healing venous ulcers, the rapid translation of basic research findings into clinical development and practical therapies is vital and cannot happen without committed industry partners", says Professor Scharffetter-Kochanek.

Despite intensive research, only a few stem cell therapies have made it to clinical application so far. RHEACELL's cell therapy is only the second cell product based on mesenchymal stem cells with a national marketing authorization in Germany. For the past three years, it has been available to treat refractory patients with non-healing venous ulcers (CVU) at specialized clinics in Germany. This therapeutic option in everyday clinical practice exists in parallel to the ongoing randomized, placebo-controlled, double-blind, multicenter, international Phase III study in refractory CVU.  

In September, the U.S. Food and Drug Administration (FDA) granted approval for the Phase III study, marking a significant clinical milestone toward potential global approval. RHEACELL has already recruited 90 study sites worldwide, underscoring the high level of interest in this innovative treatment option for CVU. 

" The FDA approval is a critical milestone - not just for patients with non-healing wounds, but also for a new product class in a relatively young field of research. The therapeutic concept of ABCB5+ MSCs presents promising new opportunities in regenerative medicine, where effective treatment options remain limited. We believe our stem cell therapy has the potential to address several serious immune and inflammatory diseases. In addition to CVU, we are advancing our development program for epidermolysis bullosa. The lack of effective treatments and the immense suffering of those affected by this rare genetic skin disorder motivates us to push forward", says Dr. med. Christoph Ganss.

Following successful Phase IIa study results, a multicenter, global Phase III study for treating this rare skin disease has now commenced. The FDA's positive feedback on the study program in epidermolysis bullosa, granting a so-called 'Regenerative Medicine Advanced Therapy (RMAT)-Fast-Track' process, has bolstered optimism among all involved, as it underlines the potential of ABCB5+ MSCs. For example, the FDA aims to use such a "fast-track process" to expedite the development of regenerative therapies for diseases with high unmet needs, offering children with the rare, life-threatening butterfly disease timely access to new therapeutic options.

"We plan to develop other drugs in our pipeline and bring them to market. To meet the expected global demand for our cells, we will significantly expand our production capacity in the near future and seek partners for global commercial distribution", says Dr. Ganss.