HQ Team
March 13, 2025: The U.S. Food and Drug Administration (FDA) has approved the expanded use of drug eculizumab (marketed as Soliris) for the treatment of pediatric myasthenia gravis (MG). Myasthenia gravis is a rare autoimmune disorder that causes muscle weakness and fatigue.
This is the first and only medicine for children 6 and older with MG.
Myasthenia gravis is a chronic autoimmune condition, which disrupts communication between nerves and muscles, leading to muscle weakness and fatigue. The condition occurs when the immune system mistakenly attacks receptors responsible for muscle activation, particularly in the eyes, face, throat, and limbs. Symptoms can range from drooping eyelids and double vision to difficulty swallowing, speaking, and breathing. In severe cases, MG can lead to life-threatening complications, such as myasthenic crisis, which requires immediate medical intervention.
While MG can affect individuals of any age, it is relatively rare in children. According to the Myasthenia Gravis Foundation of America, approximately 10-15% of MG cases occur in individuals under the age of 18. Pediatric MG often presents unique challenges, including delayed diagnosis and limited treatment options tailored specifically for children.
Eculizumab: A game-changer for pediatric MG
Eculizumab, a monoclonal antibody, works by inhibiting the complement system—a part of the immune system that contributes to the destruction of neuromuscular junctions in MG. Originally approved for adults with generalized MG, the drug has now been greenlit for pediatric use following promising clinical trial results. Studies have shown that eculizumab significantly reduces disease severity and improves muscle strength in patients with treatment-resistant MG.
Dr. Sharon Hesterlee, Chief Research Officer at the MDA, hailed the FDA’s decision as a milestone. “This approval is a testament to the progress being made in neuromuscular research. For children living with myasthenia gravis, eculizumab offers a chance to live fuller, more active lives,” she said.
Clinical trial
The FDA’s approval was based on data from a Phase 3 clinical trial involving pediatric patients in the age group of 12 to 17 with refractory generalized MG. Participants treated with eculizumab experienced a marked reduction in disease symptoms, including improved muscle strength and reduced fatigue, compared to those receiving a placebo. The drug’s safety profile was consistent with previous studies, with the most common side effects being headaches and upper respiratory infections.
The expanded use of eculizumab addresses a critical gap in pediatric MG treatment. Until now, children with MG have relied on off-label use of adult medications, corticosteroids, and immunosuppressants, which often come with significant side effects. Eculizumab offers a targeted, effective alternative with the potential to transform the lives of young patients.
Dr. John Kissel, a neurologist specializing in neuromuscular disorders, emphasized the importance of this development. “Children with MG face unique challenges, including the impact of the disease on their physical and emotional development. Eculizumab provides a much-needed option to manage symptoms and improve quality of life,” he said.
Soliris is given through an IV drip that takes about 35 minutes for adults and 1 to 4 hours for children. It is available only through a special safety program (REMS) as it can increase the risk for meningococcal infections. Patients must get a meningococcal vaccine at least two weeks before starting treatment.
Looking ahead
The approval of eculizumab for pediatric MG underscores the importance of continued research and innovation in rare diseases. Advocacy groups like the MDA are calling for increased awareness and early diagnosis of MG in children to ensure timely access to life-changing treatments.
For families affected by pediatric MG, this FDA approval represents a beacon of hope. As Dr. Hesterlee noted, “Every child deserves the chance to thrive, and this approval brings us one step closer to that goal.