Regenerative medicine, a rapidly advancing field, can be generally defined as a therapeutic methodology for the repair, regeneration, or replacement of damaged or diseased human cells and tissues. Ryoncil is an allogeneic mesenchymal stromal cell (MSC) therapy indicated for the treatment of acute graft-versus-host disease (aGvHD) for children older than two months, including adolescents and teenagers. aGvHD is a common complication of allogeneic haematopoietic stem cell transplantation (alloHCT) and is a detrimental condition with a high mortality rate. Systemic steroid therapy is generally the first line of treatment for aGvHD. According to a study by Malard and colleagues, which was published in Nature in 2020, approximately 35-50% of patients develop systemic-refractory acute graft-versus-host disease (SR-aGvHD). Furthermore, an optimal second-line therapy has not yet been introduced, highlighting the significant need for researchers to develop a safe and effective novel therapy for patients with SR-aGvHD.
Cell therapies are a fundamental aspect of regenerative medicine and consist of the administration of living cellular material into a patient to replace or regenerate damaged tissue for functional restoration. There are a variety of cells used within cell therapy, including embryonic stem cells (ESCs), induced pluripotent stem cells, and MSCs. MSCs are stromal cells that exhibit self-renewal and multipotent properties with the capacity to differentiate along mesenchymal and non-mesenchymal lineages. These include osteoblasts, myocytes, adipocytes, and chondrocytes. MSCs can be isolated from various tissues, including bone marrow, cord cells, and molar cells, and pose fewer ethical concerns compared to those associated with the collection of ESCs. SR-Ryoncil was developed and patented by Osiris Therapeutics, which later sold the intellectual property to Mesoblast Limited to initiate Phase III trials. In a single-arm, multi-centre, Phase III trial in children with SR-aGvHD, 89% of which had a severe form of the disease, 70% of children achieved an overall response by Day 28 of treatment using Ryoncil. This measure predicts the survival rates of patients with aGvHD. According to leading data and analytics company GlobalData’s Making a Difference with Regenerative Medicine, 2025 report, allogeneic cell therapies have the potential to reduce manufacturing burdens within the pharmaceutical industry. This is due to their advantageous scalability in comparison to autologous treatments as multiple patients can be treated from a single batch, consequently increasing patient accessibility. However, the usage of allogeneic cell therapies exhibits a variety of challenges. For example, larger batches of allogeneic cells create difficulties in preserving cell consistencies, requiring advanced bioprocessing techniques and intricate machinery. Furthermore, the regulatory landscape for allogeneic cell therapies presents complex procedures due to their relative novelty in comparison to autologous treatments. The multipotent characteristics of MSCs have the potential to expand into multiple clinical developments and fulfil the unmet medical demand of various diseases. As the number of patients with alloHCT increases, the development of novel and alternative means of regenerative therapy becomes increasingly important within the pharmaceutical landscape. This highlights the potential of Ryoncil’s immunomodulatory effects for the treatment of SR-aGvHD while simultaneously advancing therapeutic applications for other inflammatory diseases, thus allowing researchers to utilise MSC-based therapy options to ultimately improve patient outcomes.
