Aastrom Biosciences, Inc, a leading developer of expanded autologous cellular therapies for the treatment of severe cardiovascular diseases, has submitted to the US Food and Drug Administration (FDA) a special protocol assessment (SPA) describing the company's proposed phase-3 clinical development programme in critical limb ischemia (CLI). If the FDA concurs with the protocols outlined in the SPA, Aastrom expects to initiate the phase-3 programme in early 2011.

"We are pleased to have reached this important milestone for our CLI programme and our plans for the phase-3 pivotal clinical programme remain on track," said Tim Mayleben, president and CEO of Aastrom. "Proceeding through the FDA's SPA process will help ensure consensus with FDA on trial design and endpoints, and will provide a clear and objective path forward as we advance our first-of-a-kind therapy for severely ill CLI patients."

CLI is the most severe form of peripheral artery disease, leading to over 160,000 major limb amputations per year in the US Approximately 25% of patients will die within the six to 12 months following diagnosis, and less than 25% of patients survive four years. Therapeutic and surgical options are limited and often ineffective for the most severely affected patients.

Earlier this week, Aastrom announced that the FDA has granted fast track designation for the company's CLI programme. The FDA's fast track programme is designed to facilitate the development and expedite the review of new drugs and biologics intended to treat serious or life-threatening conditions and that demonstrate the potential to address unmet medical needs.

Aastrom Biosciences is developing expanded autologous cellular therapies for the treatment of severe cardiovascular diseases.