Mesoblast progressing towards Phase III bone marrow trial in US

Regenerative medicine specialists Mesoblast today announced that it has provided market guidance to the FDA regarding its Phase III bone marrow transplantation program, which it hopes will lead to more options for patients as well as a reduction in incidences of graft-versus-host disease (GVHD).

The company said that it intends to use the patented allogeneic adult Mesenchymal Precursor Cells (MPCs), under a United States FDA Orphan Drug Designation, to expand unrelated donor haematopoietic stem and progenitor cell numbers for use in patients with haematologic malignancies. MPCs are multipotent stem cells able to proliferate into several different cell types including for bone, cartilage and fat.

Orphan drug designation relates to therapies in development for conditions affecting 200,000 or less patients in the US.

At the moment fewer than a third of people who are in a position to take an unrelated donor bone marrow transplant actually receive one due to the fact that fully matched donors cannot be found.

Perfect matching is important due to the high risk of the sometimes fatal graft-versus-host disease (GVHD).

Through its transplantation program, Mesoblast is hoping to create a new source of unrelated donor bone marrow cells which are able to effect low risk and rapid bone marrow reconstitution in cases where there is not a perfect donor match.

The company said that based on its meeting with the FDA it expects to file an Investigational New Drug (IND) submission to the FDA to commence a Phase 3 trial for its bone marrow transplant product by the end of this year, and that it has sufficient cash reserves to fund it.

Mesoblast said that the design, size, duration, and primary endpoints of the proposed Phase III trial were based on results from the 25 patient pilot trial recently conducted at the University of Texas MD Anderson Cancer centre as well as US registry of 300 patients collected by the Center for International Blood and marrow Transplant Research.

In addition, before commencing the trial the company will seek to obtain from the FDA a binding Special Protocol Assessment (SPA), which is an agreement between the FDA and the company with regard to the design, including size and clinical endpoints, of the pivotal trial which would then be used to support an efficacy claim in a Biologic License Application (BLA).

Today's announcement failed to move investors, with Mesoblast's shares edging up just one cent on paltry volumes.