Mast Therapeutics gets orphan drug designation for experimental acute limb ischemia drug

SAN DIEGO — The Food and Drug Administration has given special designation to a drug under development by Mast Therapeutics for a rare disease that restricts the flow of blood to the limbs.

Mast announced Wednesday that the FDA had granted its drug, MST-188, orphan drug designation as a treatment for acute limb ischemia. The FDA grants the designation to treatments for diseases that affect 200,000 or fewer people. Acute limb ischemia results from embolism or thrombosis and is estimated to affect 14 out of every 100,000 people in the United States each year, according to a 1999 study.

"This designation represents further progress in our development of MST-188 as an adjunct therapy for life-threatening conditions treated with existing thrombolytic agents, such as [tissue plasminogen activator]," Mast CEO Brian Culley said. "As we previously reported, we are on track to initiate a phase-2, clinical proof-of-concept study in acute limb ischemia in early 2014."