Grafix® Featured in Plenary Session Oral Presentation at the Joint Annual Meeting of the Eastern and New England Vascular Societies

Osiris Therapeutics, Inc. (NASDAQ: OSIR), announced today that data from an evaluation of Grafix in the treatment of chronic venous leg ulcers (VLUs) was presented on Sunday September 14th, at the joint annual meeting of the Eastern Vascular Society and the New England Society for Vascular Surgery.

The data, presented by Shahab Toursavadkohi, MD, Assistant Professor of Vascular Surgery at the University of Maryland School of Medicine, highlighted the initial experience of Grafix in the treatment of chronic venous ulcers of at least 12 weeks duration that failed standard compression therapy for at least 6 weeks. Patients with an active infection were excluded from treatment. The interim study analysis evaluated 18 wounds treated with Grafix and compression therapy compared to 13 case matched control wounds with similar wound area and wound age treated with standard compression therapy alone. Overall healing rates in the Grafix patients were 50% compared to 15.4% in the control group (p < 0.05). In addition, patients in the Grafix group had significantly reduced mean time to complete healing (11.9 weeks vs 29.9 weeks, p < 0.05) and mean length of therapy (12.6 weeks vs 106.3 weeks, p=0.015) compared to the compression only group. The on-going evaluation will include up to 50 total patients.

“The data obtained thus far supports the published data available on Grafix in the treatment of venous ulcers,” said senior author Brajesh Lal, MD, Professor of Vascular Surgery at the University of Maryland School of Medicine and Chief of Vascular Surgery, Baltimore VA Medical Center. “These wounds are very difficult to treat and refractory to standard of care approaches. They account for significant morbidity and added costs to the healthcare system. Having new and innovative cellular approaches to treating VLUs allows clinicians the opportunity to improve the lives of the patients we treat while simultaneously lowering overall healthcare costs incurred due to otherwise unsuccessful interventions.”

The Eastern Vascular Society and the New England Society for Vascular Surgery Annual Meeting was held from September 11th to 14th. The meeting represented the first time the two societies held a joint annual meeting, and took place in Boston, MA.

About Venous Leg Ulcers

Venous leg ulcers, which occur when there is congestion of the venous system leading to vascular permeability and local tissue damage, account for over 2.3 million chronic wounds in the US. The ulcers often form on the sides of lower leg above the ankle and below the calf and cost the US healthcare system up to $5 billion annually.

About Grafix

Grafix is a cryopreserved placental membrane for acute and chronic wounds. It is a flexible, conforming membrane that is applied directly at the site of the wound. Grafix is produced by Osiris’ BioSmartTM Intelligent Tissue Processing which maintains the integrity of the extracellular matrix, growth factors, and endogenous fibroblasts, epithelial cells and mesenchymal stem cells of the native tissue.

About Osiris Therapeutics

Osiris Therapeutics, Inc. is the leading stem cell company, having developed the world’s first approved stem cell drug, remestemcel-L for graft versus host disease. Osiris’ products include Grafix, a cryopreserved placental membrane for acute and chronic wounds, Cartiform®, a viable cartilage mesh for cartilage repair and the latest addition to Osiris’ line of products, OvationOS®, a viable bone matrix for bone repair and regeneration. Osiris is a fully integrated company with capabilities in research, development, manufacturing and distribution. Osiris has developed an extensive intellectual property portfolio to protect the company's technology and commercial interests.

Osiris, Grafix, Cartiform and OvationOS are registered trademarks of Osiris Therapeutics, Inc. More information can be found on the company's website, www.Osiris.com. (OSIR-G)

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