Australia's regenerative medicine company, Mesoblast Limited (ASX:MSB)(PINK:MBLTY), announced positive three-month interim efficacy results from the first 20 patients enrolled in the Phase 2 heart failure trial of the proprietary allogeneic, or "off-the-shelf", adult stem cell product Revascor(TM).

Three months after receiving a single injection into damaged heart muscle of the lowest dose of Revascor(TM), patients with moderate-severe congestive heart failure demonstrated significantly improved heart muscle function.

The randomised, placebo-controlled Phase 2 trial is being run at multiple centres in the United States by Mesoblast's United States-based associated company Angioblast Systems Inc. The trial aims to compar! e one of three increasing doses of Revascor(TM) against standa! rd of ca re in up to 60 patients suffering from moderate-severe congestive heart failure, defined as a baseline ejection fraction (EF) 40% or lower by echocardiogram.

On the basis of the positive interim efficacy results and the excellent safety profile seen to date in the first group of patients receiving the lowest dose of Revascor(TM), the second group of patients set to receive the next higher dose is currently in active recruitment.

In the first 20-patient cohort, 15 were randomised to receive the lowest dose of Revascor(TM) and 5 were randomised to the control arm. While control patients with baseline EF 40 or below demonstrated an 11% mean decrease in EF over the first 3 months (mean EF values decreased from 31 to 27), patients with baseline EF 40 or below who received a single injection into damaged heart muscle of the lowest dose of Revascor(TM) showed a 37% mean increase in EF over this period (mean EF increased from 28 to 37, p=0.017). The 10-point me! an difference in absolute EF at three months between cell-treated and control patients was significant (p