AstraZeneca’s Gefurulimab Shows Efficacy but Falls Short of Leading gMG Therapies

AstraZeneca’s gefurrulimab achieved its primary endpoint in the Phase III PREVAIL trial (NCT05556096) for generalised myasthenia gravis (gMG), showing a 1.6-point improvement in MG-ADL scores versus placebo. Benefits appeared within a week and persisted through 26 weeks. However, the drug’s efficacy was below that of competitors, including UCB’s Rystiggo (2.6-point reduction), Regeneron’s cemdisiran, and AstraZeneca’s own Soliris (2.3 points) and Ultomiris (2.09 points).

Gefurulimab, a subcutaneous C5 inhibitor, also reduced QMG scores by 2.1 points by week 36 and showed a favourable safety profile, with mostly mild adverse events like headaches and injection-site reactions. If approved, it would mark AstraZeneca’s third gMG therapy, joining Soliris and Ultomiris in a $6.1 billion market. Despite modest efficacy, its self-administered dosing could help sustain AstraZeneca’s presence as market competition intensifies.

03-11-2025