Gefurulimab Improves Daily Functional Abilities in Generalized Myasthenia Gravis

Topline data were announced from a phase 3 trial evaluating gefurulimab in adults with anti-acetylcholine receptor (AChR) antibody-positive generalized myasthenia gravis.

Generalized myasthenia gravis (gMG) is a rare autoimmune disease characterized by symptoms such as slurred speech, double vision, muscle weakness, droopy eyelids and lack of balance. Gefurulimab is a dual-binding nanobody designed to bind to the C5 protein in the terminal complement cascade and prevent the overactivation of the body’s immune system. 

The randomized, double-blind, placebo-controlled PREVAIL trial (ClinicalTrials.gov Identifier: NCT05556096) evaluated the safety and efficacy of gefurulimab in 260 adults with gMG (Myasthenia Gravis Foundation of America clinical classification class II to IV) and a positive serological test for autoantibodies against AChR. 

Study participants were randomly assigned 1:1 to receive subcutaneous gefurulimab or placebo once weekly for 26 weeks. The primary endpoint was the change from baseline in Myasthenia Gravis-Activities of Daily Living (MG-ADL) total score at week 26. 

According to the Company, findings showed the study met its primary endpoint, demonstrating a statistically significant and clinically meaningful improvement from baseline in MG-ADL total score at week 26 compared with placebo; all secondary endpoints were also met. The safety profile of gefurulimab was consistent with previously reported studies of C5 inhibitors in gMG. No new safety signals were identified.

“Building on Alexion’s pioneering leadership in gMG, these positive results from the PREVAIL phase 3 trial demonstrate the potential for gefurulimab to offer rapid and sustained disease control for this patient community,” Marc Dunoyer, Chief Executive Officer, Alexion, AstraZeneca Rare Disease. “These data, reflecting patient participation across 20 countries, reinforce the established safety profile and efficacy of C5 inhibition and show the potential for gefurulimab as a first line biologic, with the convenience of a self-administered option.”

Participants who completed the initial randomized treatment period were allowed to continue into an open-label extension period. 

Full trial results will be presented at a future medical meeting. 

This article originally appeared on MPR