Osiris Completes Enrollment in First Worldwide Phase III Stem Cell Trial

BusinessWire.com, December 4, 2008

Osiris Therapeutics, one of the leading biotech companies to develop clinical therapies from adult stem cells, announced today that it has completed patient enrollment in its phase III trial for the evaluation of Prochymal in the treatment of steroid-refractory acute Graft versus Host Disease (GvHD), which is a potentially fatal complication from bone marrow transplantation. Prochymal, one of the proprietary adult stem cell therapies developed by Osiris, is formulated exclusively from mesenchymal stem cells (MSCs), which are well known for their ability to prevent inflammation and scarring in addition to their capacity to regenerate tissue. A number of studies have already demonstrated MSCs to be effective in the treatment of GvHD, such as one study recently published in the Lancet in which Le Blanc et al. reported a 55% complete response rate from MSCs that were used in the treatment of steroid-resistant GvHD. Other studies have demonstrated a 58% complete response rate in pediatric patiens with end-stage GvHD, and phase II trials evaluating Prochymal have demonstrated a 77% complete resolution rate.

A total of 244 patients are now enrolled in the phase III trial, which is designed to assess both safety and efficacy of Prochymal over a 6-month period in a double-blinded, placebo controlled study that is coordinated among 72 leading bone marrow transplant centers across the United States, Canada, the United Kingdom, Spain, Italy, Germany, Switzerland and Australia. Among other places, these 72 medical centers in the U.S. include the Fred Hutchinson Cancer Research Center in Seattle, Washington, the M.D. Anderson Cancer Center in Houston, Texas, and the Karmanos Cancer Institute in Detroit, Michigan.

According to Dr. Paul Martin of the Fred Hutchinson Cancer Research Center, professor at the University of Washington and a lead investigator in the trial, "Completion of this study's enrollment represents an outstanding accomplishment for the transplantation field. Steroid-refractory acute Graft versus Host disease poses one of the most serious and difficult to treat complications that can occur after bone marrow transplantation. Previous studies have not identified reliably effective treatments, and no drugs have been approved for this devastating disease. Transplant clinicians throughout the world now eagerly await results of this rigorous multicenter study."

Thus far, 168 patients have been treated in the United States, 31 in Canada, 27 in Europe and 18 in Australia, which included a total of 27 pediatric patients. The last patient is expected to complete the trial in May of 2009.

As Dr. Moya Daniels, director for the GvHD program at Osiris, states, "On behalf of everyone at Osiris, I would like to offer our sincere appreciation to the patients, their families, and all of the outstanding healthcare professionals who participated in this historic event. We look forward with great anticipation to the results of this landmark stem cell trial and the opportunity to make a positive difference in the care of transplant patients everywhere."

Prochymal has often been in the news lately, since Osiris and Genzyme announced a strategic alliance in November of this year for the development and commercialization of Prochymal. In the current phase III trial, which is evaluating Prochymal in patients who have failed to respond to corticosteroid treatment for acute GvHD, the key endpoints of this trial are complete response, as well as both 100-day and 180-day survival.

Osiris is also currently investigating Prochymal as a first-line agent for acute GvHD in a 184-patient phase III trial and as a therapy for Crohn's disease in a 270-patient phase III trial. Prochymal is the only stem cell therapy currently designated by the FDA as both an Orphan Drug and a Fast Track product, and it is also being developed for the repair of heart tissue following a heart attack, and for the protection of pancreatic islet cells in patients with type 1 diabetes, and for the repair of lung tissue in patients with chronic obstructive pulmonary disease. Other adult stem cell therapies developed by Osiris and currently in their pipeline include Chondrogen which is being developed for a number of applications that include arthritis of the knee. The recent partnership between Osiris and Genzyme is geared for the development and commercialization of both Prochymal and Chondrogen in countries outside of the United States and Canada. In their intellectual property portfolio, Osiris has 47 U.S. patents, each with one or more foreign counterparts.