Prospective Double-Blind Randomized Study of Single Dose Bone Marrow-Derived Mesenchymal Stromal Cells versus Placebo...

Mesenchymal stromal/stem cells (MSCs) may be a useful therapy for severe acute graft-versus-host disease (GVHD).

Patients who developed steroid-refractory grade II-IV acute GVHD were randomly assigned to treatment with one infusion of third-party 2 × 10 E⁶/kg bone marrow (BM)-MSCs (n = 12) or placebo (n = 11). The median cell dose applied was 2.2 × 10 E⁶/kg (range 1.7-4.2). The median age was 37 and 47 years in the two groups (p = 0.24), respectively.

At day 28, the BM-MSC group had six (50%) complete responders and 2 patients (17%) with a partial response. In the placebo group, the corresponding figures were three (27%) complete and three (27%) partial responders (p = 0.68). Transplantation-related mortality (TRM) 100 days after treatment was 17% in the BM-MSC group and 27% in the placebo group. At 1 year, TRM was 33% and 36% in the two groups, respectively (p = 0.59). The 100-day survival rate was 83% in the BM-MSC group and 73% in the placebo group. Five-year survival in all patients was 42% and 45% in the two groups, respectively (p = 0.87).

Although only a few patients were included in the trial, a single dose of BM-MSCs did not seem to be an effective therapy for steroid-refractory acute GVHD.