Swissmedic Invokes Rapid Authorization Procedures for Prochymal Review

Swissmedic Invokes Rapid Authorization Procedures for Prochymal Review

<0> Osiris Therapeutics, Inc.Erica Elchin, 443-545-1834 </0>

(NASDAQ: OSIR) announced today that it has been notified by Swissmedic, the Swiss agency responsible for the evaluation of drugs, that Prochymal® will be evaluated under its Rapid Authorization Procedures. This designation, also known in Switzerland as Fast Track, typically cuts the evaluation period for promising new drugs in half.

Swissmedic approved the use of the Rapid Authorization Procedures following an initial review of summary clinical data for Prochymal used for the management of acute graft-versus-host disease (GvHD). Use of the Rapid Authorization Procedures is only permitted if the clinical data demonstrates a high potential for benefit for a severe, disabling or life-threatening disease, and where no alternative treatment option exists.

As a result of this decision, Osiris intendeds to promptly submit the full Common Technical Document to Swissmedic in the electronic or eCTD format to facilitate review. The Common Technical Document for Prochymal contains over 90,000 pages of data on the stem cell drug and is similar to the applications filed in Canada and New Zealand.

Prochymal is now approved in Canada and New Zealand, and is currently available in seven other countries, including the United States, under an Expanded Access Program.

GvHD represents a major unmet medical need with no approved treatment until Prochymal. GvHD is the leading cause of transplant related mortality, in which immune cells contained within the transplanted marrow recognize the recipient as foreign and mount an immunologic attack. Severe GvHD can cause blistering of the skin, intestinal hemorrhage and liver failure. Severe GvHD is extremely painful and fatal in up to 80 percent of cases. Currently, steroids are used as first-line therapy with a success rate of only 30-50 percent. When steroids fail, treatment options are limited to immunosuppressive agents used off-label with little benefit and significant toxicities.

Prochymal is the world’s first approved drug with a stem cell as its active ingredient. Developed by Osiris Therapeutics, Prochymal is an intravenous formulation of MSCs, which are derived from the bone marrow of healthy adult donors between the ages of 18 and 30 years. The MSCs are selected from the bone marrow and grown in culture so that up to 10,000 doses of Prochymal can be produced from a single donor. Prochymal is truly an off-the-shelf stem cell product that is stored frozen at the point-of-care and infused through a simple intravenous line without the need to type or immunosuppress the recipient. Prochymal is approved in Canada and New Zealand for the management of acute graft-versus-host disease (GvHD) in children and is available for adults and children in eight countries including the United States, under an Expanded Access Program. Prochymal is currently in a Phase 3 trial for refractory Crohn’s disease and is also being evaluated in clinical trials for the treatment of myocardial infarction (heart attack) and type 1 diabetes.

Osiris Therapeutics, Inc., having developed the world’s first approved stem cell drug, Prochymal, is the leading stem cell company. The company is focused on developing and marketing products to treat medical conditions in inflammatory, cardiovascular, orthopedic and wound healing markets. In Biosurgery, Osiris currently markets Grafix® for burns and chronic wounds, and Ovation® for orthopedic applications. Osiris is a fully integrated company with capabilities in research, development, manufacturing and distribution of stem cell products. Osiris has developed an extensive intellectual property portfolio to protect the company's technology, including 48 U.S. and 144 foreign patents.

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

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