In a boost for the field of regenerative medicine, a small biotechnology company has received regulatory approval in Canada for what it says is the first manufactured drug based on stem cells.

The company, Osiris Therapeutics of Columbia, Md., said Thursday that Canadian regulators had approved its drug Prochymal, to treat children suffering from graft-versus-host disease, a potentially deadly complication of bone marrow transplantation.

“It’s really a good day for the concept and the hope behind stem cell therapies becoming a reality,” C. Randal Mills, the chief executive of Osiris, said in an interview.

Prochymal is a preparation of mesenchymal stem cells, which are obtained from the bone marrow of healthy young adult donors. The stem cells are separated out from the marrow and expanded in culture, so that one donation is enough to make as many as 10,000 doses.