Mesoblast grabs first mesenchymal stromal cell therapy FDA approval

The U.S. FDA has given the green light to Mesoblast’s remestemcel-L, branded Ryoncil, marking the first mesenchymal stromal cell (MSC) therapy approval in the U.S.

Ryoncil, an allogeneic bone marrow-derived MSC therapy, is approved for steroid-refractory acute graft versus host disease (SR-aGvHD) in children 2 months and older, including adolescents and teenagers. Ryoncil is administered via intravenous infusion given twice per week for four consecutive weeks.

MSCs can have various roles in the body and can differentiate into multiple other types of cells. The MSCs can be isolated from the bone marrow of healthy adult human donors. 

According to Mesoblast, about 50% patients who undergo an allogeneic bone marrow transplant develop aGvHD and almost half of those do not respond to steroids, the recognized first-line treatment. In a single-arm multicenter phase 3 trial of children with SR-aGvHD, 89% of whom had high severity grade C or grade D disease, 70% achieved an overall response by day 28 of treatment with Ryoncil, a measure that predicts survival in aGVHD.

Ryoncil’s immunomodulatory effects, including inhibition of T cell activation and secretion of pro-inflammatory cytokines, position Mesoblast to pursue approval for the therapy in other disease indications that involve excessive inflammation.