Klygefa (gefurulimab) / AstraZeneca, Alexion Pharma - LARVOL DELTA

Klygefa (gefurulimab) recommended for approval in the EU by CHMP for the treatment of adults with generalised myasthenia gravis (gMG) (AstraZeneca Press Release) - "The Committee for Medicinal Products for Human Use (CHMP) of the European Medicines Agency (EMA) based its positive opinion on results from the pivotal PREVAIL Phase III trial...Klygefa is approved in Japan and other countries for certain adults with gMG. Regulatory submissions based on the PREVAIL results are under review in the US, China and additional countries."

China filing • CHMP • FDA filing • Japan approval • Myasthenia Gravis

Efficacy and Safety of Gefurulimab in Generalized Myasthenia Gravis: The PREVAIL Phase 3 Randomized Clinical Trial. (PubMed, JAMA Neurol) - P3 | "Gefurulimab demonstrated both early and sustained clinical benefit in AChR-Ab+ gMG and was well tolerated, supporting its potential as a convenient, once-weekly, self-administered treatment regimen. ClinicalTrials.gov Identifier: NCT05556096."

Clinical • Journal • P3 data • Back Pain • CNS Disorders • Infectious Disease • Meningococcal Infections • Musculoskeletal Pain • Myasthenia Gravis • Pain

Gefurulimab-The First Effective Nanobody in Myasthenia Gravis Therapy. (PubMed, JAMA Neurol) - No abstract available

Journal • CNS Disorders • Myasthenia Gravis

Gefurulimab: Regulatory decision for generalised myasthenia gravis (based on PREVAIL trial) in H2 2026 (AstraZeneca) - H1 & Q2 2026 Results

Approval • Myasthenia Gravis

Self-Administered Subcutaneous Gefurulimab for Generalized Myasthenia Gravis: Primary Results from the Phase 3 PREVAIL Study (CNSF 2026) - P3 | "Gefurulimab demonstrated rapid and sustained clinical benefit, supporting a once-weekly self-administered treatment regimen for patients with AChR-Ab+ gMG."

P3 data • CNS Disorders • Myasthenia Gravis

Effect of Subcutaneous Self-Administered Gefurulimab on Ocular Muscle Function in Myasthenia Gravis in the PREVAIL Trial (EAN 2026) - P3 | "Gefurulimab, self-administered once weekly via subcutaneous injection, showed early and sustained improvements in MG-ADL and QMG ocular subdomain scores, demonstrating benefits for patients with gMG experiencing ocular symptoms."

CNS Disorders • Infectious Disease • Meningococcal Infections • Myasthenia Gravis

Health-Related Quality of Life in Patients with Generalised Myasthenia Gravis Receiving Gefurulimab in the PREVAIL Trial (EAN 2026) - P3 | "In PREVAIL, patients with AChR-Ab+ gMG receiving gefurulimab had significant improvements in HRQoL compared with those receiving placebo, demonstrated by MG-specific and general HRQoL measures."

Clinical • HEOR • CNS Disorders • Myasthenia Gravis

Phase 1 Study Evaluating Gefurulimab Pharmacokinetics and Safety Following Delivery Via Autoinjector or Prefilled Syringe With Needle Safety Device in Healthy Adults. (PubMed, Clin Ther) - P1 | "SC administration of gefurulimab by AI and PFS-SD was well tolerated with comparable exposure, meeting bioequivalence criteria."

Journal • P1 data • PK/PD data • CNS Disorders • Myasthenia Gravis

Efficacy and Safety of Gefurulimab in gMG: Primary Results From the Phase 3, PREVAIL Study (JSNE 2026) - No abstract available

Clinical • P3 data

Effect of Subcutaneous Self-Administered Gefurulimab on Ocular Muscle Function in gMG (JSNE 2026) - No abstract available

Safety and Efficacy of ALXN1720 in Adults With Generalized Myasthenia Gravis (clinicaltrials.gov) - P3 | N=261 | Active, not recruiting | Sponsor: Alexion Pharmaceuticals, Inc. | N=85 ➔ 261

Enrollment change • CNS Disorders • Myasthenia Gravis

Efficacy and Safety of Subcutaneous Self-administered Gefurulimab in Generalized Myasthenia Gravis: Primary Results From the Phase Three, Randomized, Double-blind, Placebo-controlled PREVAIL Study (AAN 2026) - P3 | "No notable differences in adverse events were observed between the 2 groups; no meningococcal infections were reported. Conclusions In PREVAIL, self-administered, once-weekly gefurulimab demonstrated rapid and sustained clinical benefit, supporting a convenient treatment regimen for patients with AChR-Ab+ gMG."

Clinical • CNS Disorders • Infectious Disease • Meningococcal Infections • Myasthenia Gravis

Alexion to showcase broad neurology pipeline at AAN 2026 with 20 presentations (Indian Pharma Post) - "A key oral presentation from the global PREVAIL Phase III study evaluates gefurulimab as a once-weekly, self-administered subcutaneous therapy in adults with AChR antibody-positive gMG. Results show a statistically significant and clinically meaningful improvement in Myasthenia Gravis Composite scores at Week 26 versus placebo, reinforcing the potential of at-home complement inhibition in a disease with significant treatment burden....Multiple presentations from the CHAMPION-NMOSD programme and real-world registries deepen understanding of disease biology and treatment impact in AQP4-Ab+ NMOSD. Key findings include transcriptomic insights, long-term efficacy data, and real-world outcomes supporting C5 inhibition therapies such as Ultomiris (ravulizumab)."

P3 data • Real-world • Myasthenia Gravis • Neuromyelitis Optica Spectrum Disorder

PK, PD, Safety, and Efficacy Study of Gefurulimab in Pediatric Patients With AChR+ Generalized Myasthenia Gravis (clinicaltrials.gov) - P3 | N=12 | Recruiting | Sponsor: Alexion Pharmaceuticals, Inc. | Trial completion date: Jul 2029 ➔ Jan 2029 | Trial primary completion date: Apr 2027 ➔ Dec 2026

Trial completion date • Trial primary completion date • CNS Disorders • Myasthenia Gravis • Pediatrics

New data on gefurulimab will highlight its potential to provide early and sustained disease control (AstraZeneca Press Release) - "Two additional posters at the MGFA Scientific Session will provide further insights into the delivery of gefurulimab via prefilled syringe (PFS) and auto injector (AI). Results from a Phase I parallel-group study in healthy adults will show that pharmacokinetic exposure following a single subcutaneous dose of gefurulimab administered via autoinjector (AI) was comparable to administration via prefilled syringe (PFS). Separately, results from a human factors validation study will demonstrate that gefurulimab AI and PFS user interfaces can be used safely and effectively with positive user experiences."

Clinical data • Myasthenia Gravis

An oral presentation at the MGFA Scientific Session will share topline results from the global PREVAIL Phase III trial evaluating gefurulimab, a dual-binding nanobody optimised for subcutaneous self-administration, in adult patients with AChR-Ab+ gMG. (AstraZeneca Press Release) - "The trial met its primary and all secondary endpoints, with gefurulimab demonstrating a statistically significant and clinically meaningful improvement from baseline in Myasthenia Gravis Activities of Daily Living (MG-ADL) total score at week 26 compared to placebo."

P3 data • Myasthenia Gravis

Alexion data presented at EAN 2025 highlights its leadership and commitment to improving patient outcomes in rare neurological diseases (AstraZeneca Press Release) - "A poster presentation will share baseline characteristics of participants enrolled in the PREVAIL Phase III trial evaluating the safety and efficacy of gefurulimab, an investigational novel, dual-binding nanobody, optimised for weekly subcutaneous administration, in adult patients with AChR-Ab+ gMG. A virtual poster will provide an overview of the ongoing Phase III global study evaluating the safety and efficacy of gefurulimab for paediatric patients with AChR-Ab+ gMG. Another virtual poster will showcase findings from a European, cross-sectional survey of physicians and anti-aquaporin-4 (AQP4) antibody positive (Ab+) neuromyelitis optica spectrum disorder (NMOSD) patients."

Clinical data • Myasthenia Gravis • Neuromyelitis Optica Spectrum Disorder

The Role of Complement in the Pathogenesis and Treatment of Myasthenia Gravis. (PubMed, Cells) - "This has led to the development of the first C5 inhibitors approved for myasthenia gravis with AchR antibodies: eculizumab, ravulizumab, and zilucoplan. Other clinical trials are currently in progress, investigating the potential therapeutic role of other targets, including the Factor B inhibition or hepatic synthesis of the C5 protein. Other proposed potential targets that have not yet been clinically tested are also discussed in this review article."

Journal • Review • CNS Disorders • Immunology • Myasthenia Gravis

A novel dual-target gene therapy strategy design with balanced gene expressions (ASGCT 2025) - " A series of dual-target constructs expressing Gefurulimab and sCD59 were constructed (Fig.1a)... By employing the insulator framework, we identified a vector construct capable of balancing the expression of dual-target genes. Both target gene exhibited relatively high expression levels. Such a vector design can be utilized for gene therapy of multi-target diseases, such as dry AMD."

Gene therapy • Dry Age-related Macular Degeneration • Gene Therapies • Ophthalmology

PK Study of Gefurulimab SC in Healthy Chinese Adult Participants (clinicaltrials.gov) - P1 | N=8 | Completed | Sponsor: Alexion Pharmaceuticals, Inc. | Recruiting ➔ Completed

Trial completion

PK, PD, Safety, and Efficacy Study of Gefurulimab in Pediatric Patients With AChR+ Generalized Myasthenia Gravis (clinicaltrials.gov) - P3 | N=12 | Recruiting | Sponsor: Alexion Pharmaceuticals, Inc. | Trial primary completion date: Jul 2027 ➔ Apr 2027

Trial primary completion date • CNS Disorders • Myasthenia Gravis • Pediatrics

The Phase 3 PREVAIL Study Assessing the Efficacy and Safety of Subcutaneous Gefurulimab in Adults with Generalized Myasthenia Gravis: Trial in Progress (AAN 2025) - P3 | "This study examines the potential of the C5 inhibitor gefurulimab as a new treatment for patients with AChR-Ab+ gMG that can conveniently be self-administered at home through once-weekly SC injection. Results from PREVAIL will inform the clinical development program of gefurulimab."

Clinical • P3 data • CNS Disorders • Myasthenia Gravis

Safety and Efficacy of ALXN1720 in Adults With Generalized Myasthenia Gravis (clinicaltrials.gov) - P3 | N=260 | Active, not recruiting | Sponsor: Alexion Pharmaceuticals, Inc. | Recruiting ➔ Active, not recruiting

Enrollment closed • CNS Disorders • Myasthenia Gravis

PK, PD, Safety, and Efficacy Study of Gefurulimab in Pediatric Patients With AChR+ Generalized Myasthenia Gravis (clinicaltrials.gov) - P3 | N=12 | Recruiting | Sponsor: Alexion Pharmaceuticals, Inc. | Trial completion date: Oct 2029 ➔ Jun 2029

Trial completion date • CNS Disorders • Myasthenia Gravis • Pediatrics

PK, PD, Safety, and Efficacy Study of Gefurulimab in Pediatric Patients With AChR+ Generalized Myasthenia Gravis (clinicaltrials.gov) - P3 | N=12 | Recruiting | Sponsor: Alexion Pharmaceuticals, Inc. | Not yet recruiting ➔ Recruiting | Initiation date: Mar 2025 ➔ Nov 2024 | Trial primary completion date: Apr 2027 ➔ Jul 2027

Enrollment open • Trial initiation date • Trial primary completion date • CNS Disorders • Myasthenia Gravis • Pediatrics