Osiris Stem Cells Safe for Heart Injury

An early experiment using adult stem cells to treat heart attack patients has allayed concerns over the treatment's safety and, surprisingly, yielded some data suggesting that stem cells might help repair an injured heart.

Osiris Therapeutics(OSIR Quote) on Sunday reported positive safety and efficacy data from a phase I study of its adult stem cell therapy, Provacel, in patients with heart disease.

In the 53-patient, double-blind, placebo-controlled study, heart attack patients given an intravenous infusion of Provacel reported lower adverse events such as abnormal heart rhythms compared with patients given a placebo.

Phase I studies are typically the proving ground for an experimental drug's safety, but in this case, the heart function of Provacel patients also appeared to improve more than that of placebo patients.

"In a phase I study, our top-line hypothesis is safety, but what we found when we looked for safety measure is that Provacel-treated patients also came up better than placebo, hinting at the drug's efficacy and showing that Provacel seems to be providing a clinical benefit for patients," said Dr. Joshua Hare, a cardiologist at the Miller School of Medicine at the University of Miami and the lead investigator of the Provacel study.

Hare presented his findings Sunday at the American College of Cardiology annual meeting in New Orleans.

Osiris Therapeutics is developing new therapies based on mesenchymal stem cells (MSCs), a form of adult stem cell that is capable of differentiating into tissues that provide rigidity or stability in the body -- bone, cartilage, fat, tendon or muscle.