The FDA has granted orphan drug designation to Alexion’s Soliris® (eculizumab) for the treatment of patients with myasthenia gravis (MG), a rare, debilitating neurologic disorder caused by uncontrolled complement activation.

“Patients with MG develop debilitating muscle weakness, impairing their ability to walk, speak clearly, swallow and, in some cases, to breathe normally, which could lead to a life-threatening myasthenic crisis,” said Martin Mackay, Ph.D., executive vice president and Global Head of R&D at Alexion. “By specifically inhibiting the terminal complement pathway, which is believed to play a pivotal role in the pathophysiology of MG, we believe that eculizumab has the potential to help patients living with this devastating rare disorder.”