United States

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 OR 15(d) of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): April 9, 2015

OSIRIS THERAPEUTICS, INC.

(Exact Name of Registrant as Specified in Charter)

Registrant’s telephone number, including area code: (443) 545 - 1800

Not Applicable

(Former name or former address, if changed since last report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

o            Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

o            Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14d-2(b))

o            Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

o            Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

ITEM 5.02. Departures of Directors or Principal Officers; Election of Directors; Appointment of Principal Officers.

On April 9, 2015, Osiris Therapeutics, Inc. (“Osiris”) issued a press release announcing the promotion of Alla Danilkovitch, Ph.D. as its Chief Scientific Officer.

Dr. Danilkovitch, age 51, is an at-will employee and will receive a base salary of $210,000 per year with the opportunity to earn an annual bonus based on performance. She has been employed with Osiris since April 2003, most recently as our Vice President, Research & Development.

Dr. Danilkovitch has over 25 years of broad biomedical research experience including stem cell biology, immunology and cancer research.  Prior to joining Osiris in April 2003, Dr. Danilkovitch conducted research at the National Cancer Institute of National Institutes of Health, the Max-Plank Institute of Biochemistry in Munich and at Moscow State University.  Dr. Danilkovitch earned a Ph.D. degree in cell biology and an M.S. degree in cellular immunology and microbiology from Moscow State University.

A copy of the Press Release, as issued on April 9, 2015, is set forth in Exhibit 99.1 hereto.

The information included herein, including Exhibit 99.1 furnished herewith, shall not be deemed to be “filed” for purposes of Section 18 of the Securities Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that section, nor shall it be incorporated by reference into any filing pursuant to the Securities Act of 1933, as amended, or the Exchange Act, regardless of any incorporation by reference language in any such filing, except as expressly set forth by specific reference in such filing.

ITEM 9.01. Financial Statements and Exhibits

(d)         Exhibits.

99.1      Press Release dated April 9, 2015.

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.  Risks and uncertainties 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. You should not unduly rely on forward-looking statements.

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the Registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

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EXHIBIT INDEX

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