Osiris Therapeutics (OSIR)

Item 8.01               Other Events.

On March 27, 2009, Osiris Therapeutics, Inc. (“Osiris” or “Company”) announced that it had elected to end enrollment at 210 patients in its Phase III clinical trial evaluating Prochymal for Crohn’s disease.  Osiris ended enrollment because it believes that there is a design flaw in the trial resulting in significantly higher than expected placebo response rates.  The decision was made after the trial’s final scheduled interim analysis showed that one of the two Prochymal dose arms had crossed a futility boundary.  The dose arm was unlikely to achieve the primary endpoint of remission because of the high placebo response rate.  This latest analysis continued to show that no serious safety concerns with the therapy and safety was not a factor in the decision to stop enrollment.

After careful discussions with the United States Food and Drug Administration, the Company elected to discontinue enrollment rather than attempt to re-power the trial.  The Company will keep the trial blinded and expects a solid data package for use in designing future trials in Crohn’s disease and to bolster Prochymal’s safety database.

The Prochymal Crohn’s program consists of two separate but related trials.  The first trial, described above, evaluates patients’ initial response to two dose levels of Prochymal as compared to placebo.  This trial was originally designed to enroll 270 subjects.  Patients responding to the initial therapy were then eligible to participate in a second, longer-term trial evaluating Prochymal as a maintenance therapy.  Because the current standard for determining response of Crohn’s patients is largely subjective, there may have been response bias in order to meet the eligibility requirements for continuation of therapy in the longer-term maintenance trial.  Accordingly, enrollment in the second trial has also ended.

Information presented in this Current Report on Form 8-K may contain forward-looking statements and certain assumptions upon which such forward-looking statements are in part based.  Forward-looking statements are subject to known and unknown risks and uncertainties and are based on potentially inaccurate assumptions that could cause actual results to differ materially from those expected or implied by the forward-looking statements.  Additional factors that could cause our actual results to differ materially from those anticipated in forward-looking statements, include the factors described in the sections entitled “Risk Factors” in our Annual Report on Form 10-K filed with the United States Securities and Exchange Commission.  You should not unduly rely on forward-looking statements.

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Item 8.01          Other Events

On July 24, 2008 at a special meeting of shareholders, the Asset Purchase Agreement and the transactions contemplated thereby were approved by the Company’s shareholders.  Over 20.2 million votes were cast for approval and 11,389 votes were cast against.  Also on July 24, 2008, a motion for a temporary restraining order filed on July 23, 2008 by Blackstone Medical, Inc., a wholly owned subsidiary of Orthofix International, N.V., seeking to prevent the technology assets closing was denied following a hearing in the United States District Court District of Massachusetts Springfield Division, clearing the way for the consummation of the technology assets closing.

Item 8.01 Other Events.

On July 23, 2008, Osiris Therapeutics, Inc. (the “Company”) received notice that Blackstone Medical, Inc. (“Blackstone”), a wholly owned subsidiary of Orthofix International, N.V., filed an action in the United States District Court District of Massachusetts Springfield Division against the Company on July 23, 2008, seeking a temporary restraining order and a preliminary injunction to prevent the Company, pending the outcome of a potential future arbitration, from closing upon, or otherwise carrying out the Company’s agreement to sell its Osteocel® business to NuVasive, Inc. (“NuVasive”) pursuant to the terms of an Asset Purchase Agreement, dated as of May 8, 2008 by and between the Company and NuVasive.  Blackstone’s claims are predicated upon, among other things, its assertion that the Company’s sale of the Osteocel business constitutes a breach of certain provisions of a distribution agreement for Osteocel between the Company and Blackstone.

The Company’s shareholders are scheduled to vote on the sale of the Osteocel business to NuVasive at a special shareholder’s meeting on July 24, 2008 at 2:00 p.m. EDT.  The Company believes that Blackstone’s actions are without merit and will take appropriate legal action as necessary to preserve the Company’s rights.  The Company does not intend to adjourn or postpone the previously scheduled special meeting of the Company’s shareholders.

A proxy statement in connection with the special meeting was mailed to shareholders on or about July 3, 2008.  Shareholders of the Company are advised to consider the matters described herein in conjunction with the proxy statement materials previously mailed to them by the Company.  Such documents may contain important information regarding the proposed sale of the Osteocel business and shareholder approval thereof.  Any shareholder desiring to do so may revoke any proxy previously submitted in accordance with the procedures described in the proxy statement.  The proxy statement and other relevant documents filed with the SEC are also available at no cost on the SEC’s website at www.sec.gov , as well as Osiris’ website at www.osiris.com . Hardcopies may also be obtained free of charge from Osiris by contacting Philip R. Jacoby, Jr., Corporate Secretary at 443-545-1834

The Company is fully committed to consummation of the transactions contemplated by the Asset Purchase Agreement as soon as practicable, although the actions taken by Blackstone could result in some delay of that occurrence.

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Item 8.01 Other Events.

On July 23, 2008, Osiris Therapeutics, Inc. (the “Company”) received notice that Blackstone Medical, Inc. (“Blackstone”), a wholly owned subsidiary of Orthofix International, N.V., filed an action in the United States District Court District of Massachusetts Springfield Division against the Company on July 23, 2008, seeking a temporary restraining order and a preliminary injunction to prevent the Company, pending the outcome of a potential future arbitration, from closing upon, or otherwise carrying out the Company’s agreement to sell its Osteocel® business to NuVasive, Inc. (“NuVasive”) pursuant to the terms of an Asset Purchase Agreement, dated as of May 8, 2008 by and between the Company and NuVasive.  Blackstone’s claims are predicated upon, among other things, its assertion that the Company’s sale of the Osteocel business constitutes a breach of certain provisions of a distribution agreement for Osteocel between the Company and Blackstone.

The Company’s shareholders are scheduled to vote on the sale of the Osteocel business to NuVasive at a special shareholder’s meeting on July 24, 2008 at 2:00 p.m. EDT.  The Company believes that Blackstone’s actions are without merit and will take appropriate legal action as necessary to preserve the Company’s rights.  The Company does not intend to adjourn or postpone the previously scheduled special meeting of the Company’s shareholders.

A proxy statement in connection with the special meeting was mailed to shareholders on or about July 3, 2008.  Shareholders of the Company are advised to consider the matters described herein in conjunction with the proxy statement materials previously mailed to them by the Company.  Such documents may contain important information regarding the proposed sale of the Osteocel business and shareholder approval thereof.  Any shareholder desiring to do so may revoke any proxy previously submitted in accordance with the procedures described in the proxy statement.  The proxy statement and other relevant documents filed with the SEC are also available at no cost on the SEC’s website at www.sec.gov , as well as Osiris’ website at www.osiris.com . Hardcopies may also be obtained free of charge from Osiris by contacting Philip R. Jacoby, Jr., Corporate Secretary at 443-545-1834

The Company is fully committed to consummation of the transactions contemplated by the Asset Purchase Agreement as soon as practicable, although the actions taken by Blackstone could result in some delay of that occurrence.

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