Company: AZN
Filing Date: 2025-07-24
Form Type: 6-K
Source: 0001654954-25-008413
Chunk: 2

Company: ASTRAZENECA PLC
Filing Date: 2025-07-24
Form: 6-K
Chunk 2
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5

gMG can occur at any age, but it most commonly begins for women before the age of 40 and for men after the age of 60. 6 Initial symptoms may include slurred speech, double vision, droopy eyelids and lack of balance; these can often lead to more severe symptoms as the disease progresses such as, impaired swallowing, choking, extreme fatigue and respiratory failure. 2,3

Gefurulimab

Gefurulimab, an investigational complement C5 inhibitor, is a novel dual-binding nanobody optimised for subcutaneous self-administration in development as a treatment for AChR-Ab+ gMG. The investigational medication 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 over-responds, 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 US for the treatment of myasthenia gravis.

PREVAIL (ALXN1720-MG-301)

PREVAIL (ALXN1720-MG-301) is a global, Phase III, randomised, double-blind, placebo-controlled, parallel, multicentre study evaluating the safety and efficacy of gefurulimab in adults with generalised myasthenia gravis (gMG). The trial enrolled 260 patients from 20 countries across North America, Europe, Asia and the Pacific region. Participants were required to have a confirmed myasthenia gravis diagnosis at least three months prior to the screening visit with a positive serological test for autoantibodies against AChR and Myasthenia Gravis Foundation of America Clinical Classification Class II to IV at screening. 7

Patients were randomised 1:1 to receive gefurulimab or placebo for a total of 26 weeks in the randomised controlled treatment period. Patients received a single weight-based loading dose on Day 1, followed by regular weight-based maintenance dosing beginning on Day 8 and once every week thereafter. The primary endpoint of the change from baseline in the Myasthenia Gravis Activities of Daily Living (MG-ADL) total score, a patient-reported scale that assesses patients' abilities to perform daily activities, was assessed at