FDA Approves Remestemcel-L for Pediatric SR-aGVHD

Remestemcel-L-rknd has been granted approval by the US Food and Drug Administration (FDA) for treatment of steroid-refractory acute graft versus host disease (SR-aGVHD) in pediatric patients aged two months and older.¹

The basis for the FDA’s approval was the findings from the phase III MSB-GVHD001 clinical study (NCT02336230). In that study remestemcel-L demonstrated significant efficacy results and safety was tolerable.

The study included 54 pediatric patients with grade B to D SR-aGVHD who were post allogeneic hematopoietic stem cell transplantation. The patients received remestemcel-L at 2 × 10⁶ cells/kg twice weekly for four weeks.

Remestemcel-L produced in this cohort an overall response rate of 70% at day 28 and a complete response rate of 30%. Partial responses to the agent were observed in 41% of the patients. Regarding response durability, the time from response at day 28 to events of disease progression, new systemic therapy for aGVHD, or mortality from any cause was 54 days.^1,2 The overall survival (OS) rate for the study cohort was found to be 74.1% at day 100 and 68.5% at day 180.

The study also showed response to be predictive of OS improvement. Survival significantly improved among patients who had a response to therapy by day 28, with an OS rate of 86.8%, as compared with those who did not respond by day 100, with an OS rate of 47.1% (P = .0001). This was similarly seen through day 180 with an OS rate of 78.9% among responders versus 43.8% among nonresponders (P = .0003).²

In the study’s safety results, the most common nonlaboratory adverse reactions were viral infectious disorders, bacterial infectious disorders, infections caused by unspecified pathogens, pyrexia, hemorrhage, edema, abdominal pain and hypertension. Each of these reactions was observed in at least 20% of the patients who received remestemcel-L in the study.¹

Based on the study data and its priority review of the biologic license application for remestemcel-L, the FDA-recommended dose 2 x 10⁶ MSC/kg body weight per intravenous infusion.  The agent is to be administered twice a week for four consecutive weeks for a total of eight infusions. Infusions of the agent must be performed three days apart and may be continued based on response at 28 days following the initial infusion.

1. FDA approves remestemcel-L-rknd for steroid-refractory acute graft versus host disease in pediatric patients. FDA. December 18, 2024. Accessed December 19, 2024. https://www.fda.gov/drugs/resources-information-approved-drugs/fda-approves-remestemcel-l-rknd-steroid-refractory-acute-graft-versus-host-disease-pediatric
2. Kurtzberg J, Abdel-Azim H, Carpenter P, et al. A phase 3, single-arm, prospective study of remestemcel-l, ex vivo culture-expanded adult human mesenchymal stromal cells for the treatment of pediatric patients who failed to respond to steroid treatment for acute graft-versus-host disease. Biol Blood Marrow Transplant. 2020;26(5):845-854. doi: 10.1016/j.bbmt.2020.01.018.