SAN DIEGO, March 25, 2013 /PRNewswire/ -- Mast Therapeutics, Inc. (NYSE MKT: MSTX) today announced that the European Commission (EC) has designated MST-188 as an orphan medicinal product for the treatment of sickle cell disease. This decision follows a positive opinion adopted by the Committee for Orphan Medicinal Products (COMP) recommending such designation. Brian M. Culley, Chief Executive Officer, said: "Now that we actively are recruiting patients in EPIC, our pivotal phase 3 study of MST-188 in sickle cell disease, we intend to pursue strategic alliances more aggressively. We believe orphan designation and the expectation of 10 years of marketing exclusivity in the EU will enhance partnering interest in Europe. In addition to enabling development in multiple countries and enhancing the overall commercial opportunity for MST-188, partnerships will help fund its development within the U.S." Mr. Culley continued: "Our recently announced plans to investigate MST-188 in acute limb ischemia, a complication of peripheral arterial disease, also may bolster our partnering efforts. Indeed, we already have been approached by at least one pharmaceutical company that wished to discuss our near- and long-term plans in arterial disease, which we announced just three weeks ago." About Orphan Medicinal Product Designation The COMP, one of seven scientific committees of the European Medicines Agency (EMA), is responsible for reviewing applications from companies seeking "orphan medicinal product designation" and making recommendations to the EC regarding these applications. Orphan medicinal product designation is for investigational medicines designed to treat rare diseases that are life-threatening or chronically debilitating and for which there is no satisfactory method of treatment or, if such a method exists, for investigational medicines that may provide significant benefit to those affected by that condition. Authorized orphan medicines benefit from 10 years of marketing exclusivity in the European Union (EU), meaning that in the 10 years after marketing authorization similar products with a comparable indication cannot be placed on the market, except in limited circumstances. This period of marketing exclusivity is extended by two years for medicines that also have complied with an agreed pediatric investigation plan. The EMA also provides a form of scientific advice specifically for orphan medicines, called protocol assistance. This allows sponsors to receive answers to questions on the types of studies needed to demonstrate the medicine's quality and benefits and risks. In addition, all designated orphan medicines are assessed for marketing authorization centrally in the EU. This allows companies to make a single application to the EMA, resulting in a single opinion and a single decision from the EC, valid in all EU member states.