Osiris Completes Enrollment in Stem Cell Trial for Knee Repair

Osiris Therapeutics, Inc. announced today that it has completed enrollment in the first human clinical trial of a stem cell therapy to repair tissue in the knee. A total of 55 patients were treated in the Phase I/II double blinded, placebo-controlled trial designed to evaluate the safety and effectiveness of Chondrogen(TM), a preparation of adult stem cells formulated for direct injection into the knee.

“Over the past 15 years, there has been much laboratory research demonstrating the ability of these stem cells to regenerate orthopedic tissues. It is gratifying to now be able to move the science from the laboratory into the clinic, where the cells can be fully evaluated in humans,” said lead investigator C. Thomas Vangsness, MD, Professor of Orthopedic Surgery at University of Southern California’s Keck School of Medicine and Chief of Sports Medicine at University Hospital.

In the U.S. alone, approximately 800,000 people each year have surgery to remove damaged or torn meniscus, a cartilage-like tissue in the knee that acts as a shock absorber. While the surgery often relieves the pain associated with a torn meniscus, patients who have this surgery are at a much greater risk for developing arthritis. Chondrogen is being studied as a treatment to regenerate meniscus in these patients.

“This study is the third clinical trial for which we have completed enrollment this year. I am pleased with the continued progress we are making and am grateful to all of the members of the Osiris team for their performance,” said C. Randal Mills, Ph.D., President and CEO of Osiris. “I would especially like to thank the patients participating in this trial, as well as our other clinical trials. It is their willingness to participate that contributes to advancements in medicine.”

The Chondrogen trial is one of five Osiris stem cell clinical trials currently active in the U.S. The company also has two ongoing Phase II trials for Graft vs. Host Disease, a life threatening complication of bone marrow transplantation, a Phase II trial for Crohn’s Disease, and a Phase I trial for the repair of heart tissue following a heart attack.

“We appreciate the hard work of the investigators and coordinators at our clinical sites and we look forward to continuing to work together to complete a high quality study,” said Michelle LeRoux Williams, Ph.D., Program Director for Chondrogen. Dr. Williams leads the team at Osiris, which has been working with FDA to move Chondrogen into human clinical trials. “Treating patients with an investigational drug in a clinical trial is a tremendous responsibility that everyone at Osiris takes very seriously.”

Osiris received clearance from FDA in 2005 to begin the first clinical trial of Chondrogen. In the study, patients were either given an injection of stem cells or placebo one week after their knee surgery. Neither the patients nor the surgeons will know what was given for the duration of the study. The study was designed to assess the safety of the Osiris stem cell and to gain preliminary efficacy data on the extent of tissue regeneration using magnetic resonance imaging, or MRI. Overall changes in the joint, as well as the patients’ perception of pain and quality of life will be tracked.

“There is currently no treatment available to regenerate a damaged meniscus. The only option for these patients is to remove the damaged tissue,” said Joel Boyd, MD, an orthopedic surgeon at TRIA Orthopaedic Research Institute in Minneapolis, Minnesota, and a United States Olympic Team physician. “The ability to give patients a simple injection into the knee that could restore the meniscus and prevent the inevitable progression to osteoarthritis would be a significant advancement in the treatment of knee pain.”

About Osiris Therapeutics

Osiris(R) Therapeutics, Inc. is a leader in adult stem cell therapy. The stem cells produced by Osiris are obtained from adult volunteer donors, avoiding the technical problems and controversy surrounding other stem cell technologies. Using proprietary methods, these cells are grown in culture to very high numbers, allowing a single donor’s cells to treat thousands of patients. These cells have been used in patients unrelated to the donor, without rejection, eliminating the need for donor matching and recipient immune suppression. Once transplanted, the cells have been shown to promote healing of damaged or diseased tissues.

The Company’s current focus includes the use of adult stem cells to improve outcomes in bone marrow recipients being treated for cancer, to treat Crohn’s Disease, to repair damage following a heart attack and prevent congestive heart failure, and to prevent and treat arthritis.