X0202 4 2008-03-24 0 0001360886 OSIRIS THERAPEUTICS, INC. OSIR 0001008317 FRIEDLI PETER C/O OSIRIS THERAPEUTICS, INC. 7015 ALBERT EINSTEIN DRIVE COLUMBIA MD 21046 1 0 1 1 Chairman Convertible Promissory Note 12.17 2008-03-24 4 P 0 2500000 12.17 A 2008-03-25 2008-11-30 Common Stock 205423 1205423 D Convertible promissory note pursuant to a private placement intended to qualify under Regulation S of the Securities Act of 1933, as amended. The Note bears interest at the rate of 2% per annum, payable upon maturity on November 30, 2008. The Note is convertible at any time at the sole discretion of the holder into shares of the Company's common stock at the conversion price of $12.17 per share, and redeemable by the Company with 30-days prior notice. The Note affords the holder registration rights in respect of any shares issued uon conversion Peter Friedli 2008-03-26