Osiris' stem cell drug fails in two late-stage trials

(Reuters) - Adult stem cell research firm Osiris Therapeutics Inc said two late-stage trials testing its lead product to treat a rare condition that affects bone marrow transplant patients failed to meet the main study goals.

Osiris shares sank 52 percent to $5.89 in trading before the bell from their Friday’s close of $12.21 on Nasdaq.

The drug, Prochymal, did not show any statistical benefit over a dummy drug in either of the trials that were evaluating the drug in Graft vs Host Disease (GvHD).

The two trials were testing the drug in acute GvHD and in steroid refractory setting. GvHD is a potentially fatal disease in which immune cells from a transplanted bone marrow recognize the recipient’s body as foreign and attack it.

Prochymal is designed to work by interacting with the immune cells in the body, reducing inflammation and assisting in tissue repair.

However, the company said the drug significantly improved response rates in patients with steroid-refractory gastrointestinal GvHD and also in children.

“We will meet with the FDA as soon as possible to discuss the most appropriate and efficient path forward for Prochymal in this life-threatening indication,” Chief Executive Randal Mills said in a statement.

Reporting by Esha Dey in Bangalore; Editing by Gopakumar Warrier