Myasthenia Gravis Treatment Gets First FDA Approval Since 1950s
For more than 60 years, steroids and acetylcholinesterase inhibitors have been widely used as therapeutic options for patients with myasthenia gravis (MG), mostly because alternative means of immunotherapy have always been associated with serious adverse events (AEs).
Last night, Alexion Pharmaceuticals, Inc. announced that the U.S. Food and Drug Administration (FDA) has approved Soliris (eculizumab) as a new treatment for adult patients with generalized myasthenia gravis (gMG) who are anti-acetylcholine receptor (AchR) antibody-positive. The drug exhibited clinical benefit for these patients who had previously failed immunosuppressive treatment and continued to suffer from significant unresolved disease symptoms.
gMG is a debilitating, chronic and progressive autoimmune neuromuscular disease that can occur at any age. In patients with the condition, antibodies block, alter, or destroy the acetylcholine receptors at the neuromuscular junction. Symptoms most commonly revolve around weakness in an array of muscles, causing difficulties in seeing, walking, talking, swallowing, and breathing.
Soliris is a complement inhibitor. The complement cascade, when activated in an uncontrolled manner, plays a pivotal role in gMG, as well as serious ultra-rare disorders like paroxysmal nocturnal hemoglobinuria (PHN) and typical hemolytic uremic syndrome (aHUS)—the other indications that Soliris is approved for.
“Today’s approval is a significant milestone for Alexion and, more importantly, for the subset of patients with anti-AchR antibody-positive gMG who continue to suffer from significant unresolved disease symptoms despite existing treatment options,” said John Orloff, M.D., Executive Vice President and Head of Research & Development at Alexion in a press release. “We are proud that we could apply our deep understanding of complement biology to develop Soliris for the treatment of patients with this debilitating neuromuscular disorder.”
In March, the FDA accepted Alexion’s supplemental Biologics License Application (sBLA) to extend the indication of the drug based on data from the recently published Phase 3 REGAIN study (MG-301) and its long-term open-label extension study (MG-302). That same data led to the European Commission’s (EC) approval of Soliris in August and the FDA’s approval yesterday.
Last year, Rare Disease Report sat down with the lead investigator of the REGAIN study, James Howard Jr, MD of the Department of Neurology at the University of North Carolina School of Medicine, to discuss the pivotal trial.
“This is a landmark day for the members of the U.S. myasthenia gravis community, who have not seen a therapy approved for generalized myasthenia gravis in more than 60 years,” said Nancy Law, Chief Executive Officer of the Myasthenia Gravis Foundation of America (MGFA). “It is particularly significant that this approval of Soliris will provide a new option for those with gMG and especially for those who do not respond adequately to or cannot tolerate standard treatment options.”
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