Successful Phase III trial of allogeneic mesenchymal stem cell product MSC-100-IV to treat steroid refractory acute Graft versus Host Disease .- Mesoblast Ltd.

Mesoblast Limited announced that the Phase III trial of its allogeneic mesenchymal stem cell product candidate MSC-100-IV (remestemcel-L) in children with steroid refractory acute Graft versus Host Disease (aGVHD) has successfully met the primary endpoint of Day 28 overall response (OR, complete + partial response) rate.

In the 55 children enrolled in Mesoblast�s open-label Phase III trial conducted across 32 sites in the United States, the Day 28 OR rate was 69%, a statistically significant increase compared to the protocol-defined historical control rate of 45% (p=0.0003). Among patients who received at least one treatment infusion and were followed up for 100 days (n=50), the mortality rate was 22%. This is in contrast to Day 100 mortality rates as high as 70% in patients who fail to respond to initial steroid therapy. The treatment regimen of remestemcel-L was well tolerated and the incidence of adverse events was consistent with that expected from the underlying disease state and in line with previous remestemcel-L use. These safety and efficacy results are consistent with Mesoblast�s prior experience using remestemcel-L in 241 children treated under an expanded access protocol, where Day 28 OR correlated with Day 100 survival.

The Phase III study results were presented at the tandem annual scientific meetings of the Center for International Blood & Marrow Transplant Research (CIBMTR) and the American Society of Blood and Marrow Transplantation (ASBMT) being held in Salt Lake City from February 21-25, 2018.Full results for this ongoing trial will be provided in CY Q2 2018.