The U.S. Food and Drug Administration has granted orphan drug designation for Alexion Pharmaceuticals' Soliris (eculizumab) to treat patients with Myasthenia Gravis (MG), a rare, debilitating neurologic disorder caused by uncontrolled complement activation. In patients with MG, uncontrolled complement activation due to antibodies directed at the neuromuscular junction can ultimately lead to profound and debilitating weakness of various muscle groups throughout the body.

Alexion said it is enrolling patients in a multinational, placebo-controlled registration trial of Soliris in patients with refractory generalized MG. More information on this trial is available at under the identifier NCT01997229.

Soliris is a complement inhibitor and was first approved in 2007 to treat patients with paroxysmal nocturnal hemoglobinuria (PNH). The drug was also approved in 2011 to treat patients with atypical hemolytic uremic syndrome (aHUS).

Soliris wasgranted orphan drug designation in January 2014 to prevent delayed graft function in renal transplant patients. DGF is an early and serious complication of organ transplantation that is characterized by the failure of a transplanted organ to function normally immediately following transplantation.

The FDA, through its Office of Orphan Products Development), grants orphan status to drugs and biologic products that are intended for the safe and effective treatment, diagnosis, or prevention of rare diseases or disorders that affect fewer than 200,000 people in the United States. Orphan drug designation provides a drug developer with certain benefits and incentives, including a period of marketing exclusivity if regulatory approval is ultimately received for the designated indication.