Osiris Therapeutics, Inc. (NASDAQ: OSIR), a leading stem cell therapeutic company, announced today the appointment of Richard W. Hunt as Chief Financial Officer effective July 23, 2008. He will report directly to C. Randal Mills, Ph.D., President and Chief Executive Officer. Additionally, Philip R. Jacoby, Jr., the company’s controller and interim CFO, has been promoted to the position of Vice President of Finance.

“Rich is an exciting addition to the Osiris management team,” said Dr. Mills. “His extensive experience in senior leadership positions in publicly traded healthcare companies will benefit Osiris as we progress towards our now near-term goal of commercializing the world’s first stem cell drug.”

Dr. Mills went on to say, “Phil Jacoby has performed exceptionally well in the role of interim CFO. The entire Osiris board is truly appreciative of his efforts, and we look forward to his continued contribution in his new position.”

Mr. Hunt spent 18 years in progressive leadership positions with Baxter Healthcare/American Hospital Supply, ultimately as Vice President of Corporate Audit. Following Baxter, Mr. Hunt was appointed Chief Financial Officer of Global Healthcare Exchange, an e-commerce venture formed by a group of leading healthcare companies including Johnson & Johnson, GE Medical Systems, Abbott, and Baxter. Mr. Hunt then served as CFO of Neighborcare, a publicly traded pharmaceutical service provider, until its $1.7 billion acquisition in 2005. Mr. Hunt also served as CFO of Healthextras, a $1.8 billion publicly traded pharmacy benefit management service provider. Mr. Hunt started his healthcare career with Searle Pharmaceuticals. Mr. Hunt is a certified public accountant, (CPA) and holds a Bachelor of Science degree in accounting from Northern Illinois University and a Masters in Business Administration from Pepperdine University.

About Osiris Therapeutics

Osiris Therapeutics, Inc. is a leading stem cell therapeutic company focused on developing products to treat medical conditions in the inflammatory, orthopedic and cardiovascular areas. Prochymal is being evaluated in Phase III clinical trials for three indications, including acute and steroid refractory Graft versus Host Disease and also Crohn's disease, and is the only stem cell therapeutic currently designated by FDA as both an Orphan Drug and Fast Track product. Osiris also has partnered with Genzyme Corporation to develop Prochymal as a medical countermeasure to nuclear terrorism and other radiological emergencies.