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  6. FDA approves remestemcel-L-rknd for steroid-refractory acute graft versus host disease in pediatric patients
  1. Resources for Information | Approved Drugs

FDA approves remestemcel-L-rknd for steroid-refractory acute graft versus host disease in pediatric patients

On December 18, 2024, the Food and Drug Administration approved remestemcel-L-rknd (Ryoncil, Mesoblast, Inc.), an allogeneic bone marrow-derived mesenchymal stromal cell (MSC) therapy, for steroid-refractory acute graft versus host disease (SR-aGVHD) in pediatric patients 2 months of age and older. Ryoncil is the first FDA-approved MSC therapy.

Full prescribing information for Ryoncil will be posted here

Efficacy and Safety

Efficacy was evaluated in MSB-GVHD001 (NCT02336230), a multicenter, prospective, single-arm study in 54 pediatric patients with SR-aGVHD after allogeneic hematopoietic stem cell transplantation (HSCT). Patients had Grade B to D SR-aGVHD, excluding Grade B skin alone (International Blood and Marrow Transplantation Registry Severity Index Criteria). SR-aGVHD was defined as aGVHD progressing within 3 days or not improving within 7 consecutive days of methylprednisolone (2 mg/kg/day or equivalent). Patients receiving a second-line aGVHD therapy prior to screening were excluded.

The main efficacy outcome measures were overall response rate (ORR) at Day 28 and duration of overall response. The ORR included complete and partial response rates (CR and PR). ORR at Day 28 was 70% (95% confidence interval, CI: 56.4, 82.0), including a CR rate of 30% (95% CI: 18.0, 43.6) and a PR rate of 41% (95% CI: 27.6, 55.0). The median duration of response calculated from response at Day 28 to either progression, new systemic therapy for aGVHD, or any cause death, was 54 days (range 7, 159+).

The most common nonlaboratory adverse reactions (incidence ≥20%) were viral infectious disorders, bacterial infectious disorders, infection – pathogen unspecified, pyrexia, hemorrhage, edema, abdominal pain and hypertension.

The recommended dose is 2 X 106 MSC/kg body weight per intravenous infusion given twice a week for 4 consecutive weeks for a total of 8 infusions. Infusions are administered at least 3 days apart. Treatment may be continued based on response at 28 days after initial remestemcel-L-rknd.

Expedited Programs

Remestemcel-L-rknd has fast track, orphan drug and priority review designations. FDA expedited programs are described in the Guidance for Industry: Expedited Programs for Serious Conditions-Drugs and Biologics. A description of FDA expedited programs for regenerative medicine advanced therapies is in the Guidance for Industry: Expedited Programs for Regenerative Medicine Therapies for Serious Conditions.

Healthcare professionals should report all serious adverse events suspected to be associated with the use of any medicine and device to FDA’s MedWatch Reporting System or by calling 1-800-FDA-1088.

For assistance with single-patient INDs for investigational oncology products regulated by the Center for Biologics Evaluation and Research, healthcare professionals may email OTPRPMS@fda.hhs.gov.

Follow the Oncology Center of Excellence on X: @FDAOncology.

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