AstraZeneca: Alexion advances pioneering leadership in gMG care with data at 2026 AANEM Annual Meeting and MGFA Scientific Session

Alexion, AstraZeneca Rare Disease, will advance its ambition to transform outcomes for people living with generalised myasthenia gravis (gMG) across 15 presentations at the American Association of Neuromuscular & Electrodiagnostic Medicine (AANEM) Annual Meeting and the Myasthenia Gravis Foundation of America (MGFA) Scientific Session in Orlando, Florida, 29 September to 2 October 2026.

Key presentations include new 52-week data from the PREVAIL Phase III trial evaluating the long-term efficacy and safety of novel dual-binding nanobody gefurulimab, a subcutaneous self-administered C5 inhibitor, in adults with anti-acetylcholine receptor (AChR) antibody-positive (Ab+) gMG. Additionally, new analyses from the PREVAIL trial through week 26 will demonstrate the impact of gefurulimab on clinical outcomes and also evaluate quality of life (QoL) endpoints. An oral presentation will share new pre-clinical data evaluating the potential of a novel functional biomarker for monitoring disease progression and treatment response in MG.

Christophe Hotermans, Senior Vice President, Head of Global Medical Affairs, Alexion, said: "Alexion's robust data at the AANEM and MGFA Scientific Session reinforce how we continue to pioneer new possibilities to advance gMG care and deliver on our commitment to this community. Open-label extension data from the pivotal PREVAIL Phase III trial will demonstrate how gefurulimab impacts functional improvements through 52 weeks in adults with gMG, building on results previously shared through 26 weeks. Together with new analyses from the PREVAIL trial showing reduced risks of gMG-related hospitalisations and rescue therapy use, these data further demonstrate the potential for gefurulimab to be a convenient self-administered treatment option that can deliver rapid and sustained disease control for people living with this unpredictable rare disease."

Long-term data and additional analyses from the PREVAIL Phase III trial strengthen evidence supporting gefurulimab as a meaningful treatment option in gMG

Results from the open-label extension (OLE) of the PREVAIL Phase III trial will highlight sustained disease control up to 52 weeks as measured by change from baseline in Myasthenia Gravis Activities of Daily Living (MG-ADL), Quantitative Myasthenia Gravis (QMG) and Myasthenia Gravis Composite (MGC) total scores. Results demonstrate that patients receiving gefurulimab maintained clinical improvements through the OLE (Least squares mean: 95% CI: MG-ADL, −5.3 (−5.8, −4.8); QMG, −5.3 (−6.0, −4.6); MGC, −9.4 (−10.3, −8.5). In patients who switched to gefurulimab from placebo at week 26, improvements were seen at the first assessments after treatment initiation and sustained through week 52 (Least squares mean: 95% CI: MG-ADL, −4.9 (−5.4, −4.4); QMG, −4.6 (−5.4, −3.9); MGC, −8.3 (−9.2, −7.3). Gefurulimab was well-tolerated and no meningococcal infections were reported.

Separately, a post-hoc analysis of PREVAIL long-term data will show that patients receiving gefurulimab achieved an early onset response to therapy and minimal symptom expression, sustained through 52 weeks with patients seeing response rates as early as week one.

Additionally, an oral presentation will highlight new data showing reduced risks of gMG-related hospitalisations and rescue therapy use with gefurulimab at week 26 compared to placebo in the PREVAIL Phase III trial.

Preclinical analyses using an in vivo model support the potential of an integrated platform to evaluate disease progression and treatment response in MG

An oral presentation will highlight a preclinical translational biomarker platform that combines in vivo nerve-evoked muscle function assessments with neuromuscular junction (NMJ) morphology analysis in a rodent model of MG. The findings will suggest that the platform could support the characterisation of NMJ injury, evaluation of disease progression and assessment of treatment response. In this model, C5 inhibition was associated with partial recovery of NMJ structure and muscle function, supporting further investigation of the platform and its potential utility in preclinical MG research and future translatability to the clinic.

Clinical data supports potential clinical relevance and adoption of ME&MG^TM symptom tracking application to enhance patient care

An oral presentation in collaboration with Ad Scientiam will share data from the ME&MG^TM open study showing that the ME&MG^TM application's digital biomarkers reflect gMG severity, as classified by MGFA groups, supporting its potential in clinical practice.*

Alexion presentations during the 2026 AANEM Annual Meeting and MGFA Scientific Session

*Ad Scientiam research study supported by Alexion

Notes

Alexion
Alexion, AstraZeneca Rare Disease, is focused on serving patients and families affected by rare diseases and devastating conditions through the discovery, development and delivery of life-changing medicines. A pioneering leader in rare disease for more than three decades, Alexion was the first to translate the complex biology of the complement system into transformative medicines, and today it continues to build a diversified pipeline across disease areas with significant unmet need, using an array of innovative modalities. As part of AstraZeneca, Alexion is continually expanding its global geographic footprint to serve more rare disease patients around the world. It is headquartered in Boston, US.

AstraZeneca
AstraZeneca (LSE/STO/NYSE: AZN) is a global, science-led biopharmaceutical company that focuses on the discovery, development, and commercialisation of prescription medicines in Oncology, Rare Disease, and BioPharmaceuticals, including Cardiovascular, Renal & Metabolism, and Respiratory & Immunology. Based in Cambridge, UK, AstraZeneca's innovative medicines are sold in more than 125 countries and used by millions of patients worldwide. Please visit astrazeneca.com and follow the Company on Social Media @AstraZeneca.

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