AstraZeneca Reports Positive Results for Experimental gMG Therapy

Rare Daily Staff

AstraZeneca announced that a Phase 3 study of its experimental therapy, gefurulimab, demonstrated a statistically significant and clinically meaningful improvement in functional activities of daily living in adults with the rare autoimmune condition generalized myasthenia gravis.

AstraZeneca acquired gefurulimab through its acquisition of Alexion.

Generalized myasthenia gravis (gMG) is a chronic neuromuscular disease that leads to loss of muscle function and severe weakness. People living with gMG may initially experience slurred speech, double vision, droopy eyelids, and muscle weakness. As the disease progresses, symptoms can become more severe, including extreme fatigue, difficulty swallowing, choking, and respiratory failure.

Gefurulimab works by binding to the C5 protein in the terminal complement cascade, a part of the body’s immune system. When activated in an uncontrolled manner, the complement cascade can over-respond, leading the body to attack its own healthy cells. Gefurulimab’s concurrent binding to serum albumin provides an extended half-life, enabling once-weekly dosing. Gefurulimab has been granted Orphan Drug Designation in the United States for the treatment of myasthenia gravis.

The phase 3 trial in adults with AChR antibody-positive gMG (AChR Ab+ gMG) showed that gefurulimab met its primary and all secondary endpoints. Data demonstrated a statistically significant and clinically meaningful improvement from baseline in Myasthenia Gravis Activities of Daily Living total score at week 26 compared to placebo.

Gefurulimab was well tolerated, and the safety profile was consistent with previous trials of C5 inhibitors in gMG, with no new safety signals observed. These data will be presented at an upcoming medical meeting.

“Rapidly fluctuating symptoms and the unpredictable disability associated with gMG can affect nearly every aspect of a patient’s life, making early intervention and sustained disease control a critical treatment goal,” said Kelly Gwathmey, Chief of the Neuromuscular Division at Virginia Commonwealth University in Richmond and principal investigator in the trial. “A once-weekly, self-administered C5 treatment option would offer patients greater convenience and independence in managing their condition, empowering them to have more control over their therapy.”