OSIRIS RELEASES DATA FROM CROHN'S DISEASE STUDY

Osiris Therapeutics announced positive results from a pilot Phase II study using Prochymal for the treatment of patients with moderate to severe Crohn's disease who had failed to respond to standard treatments such as steroids and Remicade (infliximab). In the study, every patient evaluated reported a reduction in Crohn's Disease Activity Index (CADI) after receiving two infusions of Prochymal. There was a statistically significant decrease in mean CDAI scores of 105 points by day 28 from 341 to 236.

The trial was a prospective, randomized, open-label trial, conducted at four centers in the U.S. Patients with moderate to severe Crohn's disease, defined as having a CDAI of at least 220, were given two infusions of Prochymal seven days apart. A total of 10 patients were treated, with nine patients evaluated through the 28-day follow-up. Patients were divided into two groups and received either low dose (2 million cells per kilogram) or high dose (8 million cells per kilogram) of the drug on an outpatient basis. In addition to safety parameters, patients were evaluated for changes in CDAI and improvement in the Inflammatory Bowel Disease Questionnaire (IBDQ).

Entering the trial, the average CDAI score at baseline was 341. During the study, one-third of the patients had a reduction of CDAI of greater than 100 points within 14 days of treatment. Mean IBDQ scores improved significantly from baseline to day 28 (113 to 146). One-third of the patients reported IBDQ scores of at least 170, indicating they had achieved clinical remission of their disease. Although not reaching statistical significance, there appeared to be correlation between dose and response. Patients receiving the high dose had a 72-point greater reduction in CDAI than those receiving low dose. There were no infusional toxicities, nor were there any treatment-related severe adverse events.

Prochymal is a preparation of mesenchymal stem cells specially formulated for intravenous infusion. The stem cells are obtained from the bone marrow of healthy adult donors. Prochymal is also being evaluated in Phase III clinical trials for the treatment of graft versus host disease had has been granted fast-track and orphan drug status by the FDA for the indication.