AlloSource and Osiris Therapeutics Partner to Bring New Allograft Technology to AlloSource Donor Communities.

AlloSource Becomes First Full-Service Tissue Bank to Provide the Complete Range of Bone Growth Substitute Allografts 

CENTENNIAL, Colo. -- Osiris Therapeutics and AlloSource announced today that they have reached a multi-year agreement for the supply of orthopedic tissue. Under the terms of the agreement, AlloSource will provide bone matrix to Osiris for use in the production of its Osteocel product line. Osteocel will be available from AlloSource to patients in all of AlloSource's donor areas across the country. AlloSource is one of the nation's largest non-profit providers of bone and soft tissue allografts, as well as allograft skin for burn applications, for use in surgical procedures.

"Today AlloSource becomes the only full-service tissue bank to offer the complete range of bone growth allografts," said Tom Cycyota, AlloSource President and CEO. "The addition of the exciting Osteocel product line allows us to provide osetoconductive, osteoinductive and now osteogenic tissue and helps us continue our commitment to offering a full range of quality tissue and innovative new products to our customers."

Osteocel is the first product containing viable stem cells for the repair, replacement or reconstruction of bone defects. Osiris leveraged its extensive stem cell experience and intellectual property in the formulation of the product. Following nearly 12 years of research and development, Osteocel was launched in July of 2005. The product is used as an alternative to autograft. Osteocel helps reduce the complication rates associated with autograft, which can be as high as 35%.

"We are pleased to be partnered with AlloSource, one of the most trusted providers of allograft tissue in the United States," said C. Randal Mills, Ph.D., President and CEO of Osiris. "This agreement serves to increase our capacity to produce Osteocel, but most importantly, it puts patient safety first by working with a top-notch AATB-accredited tissue bank."

This arrangement leverages the strengths of both organizations to bring the Osteocel technology to more patients across the country. To ensure that the technology is made available to the communities from which it is sourced, the agreement enables AlloSource to act as a non-exclusive distributor of Osteocel in AlloSource's local donor communities. Osiris will continue to be the sole manufacturer of the product.

About AlloSource

Founded in 1994, Centennial, Colorado based AlloSource continues to increase the availability of high quality, safe allografts. Showing respectful appreciation for the gift of donation, AlloSource saves and improves lives by maintaining the highest standards in recovery, processing and storage of human tissue and cells, while striving to develop new therapeutic technologies. AlloSource provides service to the country's most reputable non-profit organ procurement organizations that have direct input and oversight into the company's business operations. AlloSource is accredited by the American Association of Tissue Banks and operates three facilities in Centennial, Salt Lake City and Cincinnati. For more information, visit www.allosource.org.

About Osiris Therapeutics

Osiris Therapeutics, Inc. is a leading stem cell therapeutics company focused on developing and marketing products to treat medical conditions in the inflammatory, orthopedic and cardiovascular areas. Osiris currently markets and sells Osteocel for regenerating bone in orthopedic indications. Prochymal[TM] is in Phase 3 clinical trials and is the only stem cell therapeutic currently designated by FDA as both an Orphan Drug and Fast Track product. The Company's pipeline of internally developed biologic drug candidates under evaluation also includes Chondrogen[TM] for regenerating cartilage in the knee, and Provacel[TM] for repairing heart tissue following a heart attack. Osiris is a fully integrated company, having developed stem cell capabilities in research and development, manufacturing, marketing and distribution. Osiris has developed an extensive intellectual portfolio to protect the company's technology in the United States and a number of foreign countries including 46 U.S. patents and over 165 foreign patents owned or licensed. More information can be found on the Company's website, www.Osiris.com.