Positive Data on Stem Cell Treatment for Acute MI Reported


February 12, 2009

February 12, 2009 - Osiris Therapeutics Inc. yesterday announced final two-year results for the company's trial evaluating Prochymal — a proprietary formulation of adult stem cells — for the treatment of acute myocardial infarction.

Prochymal is designed to provide therapeutic benefit by controlling inflammation, promoting tissue regeneration and preventing scar formation. Prochymal is a preparation of mesenchymal stem cells specially formulated for intravenous infusion. The stem cells are obtained from the bone marrow of healthy adult donors.

The double-blind, placebo-controlled study of 53 patients, which evaluated safety and preliminary efficacy, found heart attack patients receiving the intravenous therapy had lower rates of adverse events and significantly improved heart function.

Study findings included:

- The trial met its primary endpoint demonstrating safety of Prochymal in the acute MI setting.
- Patients receiving Prochymal had fewer adverse events compared to placebo.
- A lower percentage of patients treated with Prochymal required repeat hospitalization.
- Patients receiving Prochymal had reduced incidence of cardiac arrhythmia.
- Patients receiving Prochymal had a significant and durable improvement in cardiac function.

"This placebo controlled study was truly first of its kind and the data produced is promising," said Timothy Henry, M.D., director of research at the Minneapolis Heart Institute Foundation at Abbott Northwestern. "It clearly suggests that allogeneic adult stem cells have significant potential to improve recovery following a heart attack and can prevent long term adverse effects. Given the fact that we can administer this drug through a standard IV in an acute setting, Prochymal could become an integral part of standard of care for treatment of heart attacks everywhere.”

For more information: www.Osiris.com.