Prochymal achieves response rate of 63% when used as rescue therapy in children suffering from GvHD

Osiris Therapeutics, Inc. (NASDAQ:OSIR) today reported that a new study shows Prochymal achieved an overall response rate of 63% when used as a rescue therapy in children suffering from severe treatment resistant graft vs. host disease (GvHD). Furthermore, the study demonstrates that response to Prochymal significantly improved survival. The data are being presented at the 2010 BMT Tandem Meeting by the study’s lead author, Joanne Kurtzberg, M.D., Professor of Pediatrics and Pathology and Director of the Pediatric Blood and Marrow Transplant Program at Duke University Medical Center (Abstract #40).

“Treatment-resistant GvHD remains a significant challenge in transplantation and results in poor outcomes and high mortality”

“Treatment-resistant GvHD remains a significant challenge in transplantation and results in poor outcomes and high mortality,” said Dr. Kurtzberg. “We are encouraged to see high response rates and improved survival in children with disease unresponsive to other treatments. Because of its excellent risk-benefit profile, Prochymal should be considered in pediatric patients with GvHD that does not respond to steroids.”

Highlights from the Study

The study (Protocol 275) evaluated Prochymal as a rescue therapy in 59 pediatric patients with severe, treatment resistant GvHD. Patients were evaluated for response to Prochymal at day 28 of therapy and survival through day 100.

The children in this study had severe, refractory GvHD:

• At study entry, six patients (10%) had Grade B, 18 patients (31%) had Grade C and 35 patients (59%) had Grade D GvHD. Grades C and D represent the most severe forms of GvHD.
• Prior to treatment with Prochymal, patients had GvHD that was unresponsive to an average of three lines of therapy for an average of 46 days.

Response to treatment with Prochymal was prompt and clinically meaningful:

• Overall response to treatment with Prochymal at 28 days was 63%.
• Response to Prochymal at day 28 significantly improved survival over patients who progressed (78% vs. 9%, p<0.05).

Prochymal also continued to demonstrate a strong safety profile. Prochymal infusions were well tolerated and no serious adverse events were attributed to treatment with the stem cells.

The full study results are included in a February supplement issue of the peer-reviewed journal, Biology of Blood and Marrow Transplantation.