Alexion reported new Phase III PREVAIL data showing statistically significant improvement with gefurulimab in generalized myasthenia gravis, alongside KOMET sub-study findings highlighting pain and symptom reductions with Koselugo in adults with NF1 plexiform neurofibromas.
Written By: Dr. Anuja Badgujar, BDS
Reviewed By: Pharmacally Editorial Team
Alexion Pharmaceuticals reported new data from the Phase III PREVAIL trial of gefurulimab in generalized myasthenia gravis (gMG) and a qualitative sub-study from the Phase III KOMET trial evaluating Koselugo (selumetinib) in adults with neurofibromatosis type 1 plexiform neurofibromas (NF1-PN). The findings were disclosed in advance of the American Academy of Neurology Annual Meeting 2026 taking place from April 18–22 in Chicago.
PREVAIL Phase III: Gefurulimab shows significant improvement in gMG
New results from the global PREVAIL Phase III trial (NCT05556096) showed that investigational dual-binding nanobody gefurulimab, administered once weekly by subcutaneous self-injection, achieved statistically significant and clinically meaningful improvement in the secondary endpoint of change in Myasthenia Gravis Composite score at Week 26 compared with placebo. The reported treatment difference was −3.1 (0.69), with P<0.0001.
The company said these findings expand on previously presented data and support the potential of gefurulimab as a self-administered treatment option for adults with anti-acetylcholine receptor antibody-positive gMG, with rapid and sustained improvements observed through 26 weeks.
KOMET sub-study: Koselugo linked to symptom and pain reductions in NF1-PN
A qualitative sub-study from participants enrolled in the Phase III KOMET trial (NCT04924608) reported that adults receiving Koselugo experienced noticeable reductions in pain, tingling, and plexiform neurofibroma size. Patients also reported improvements in sleep, fatigue, and body movement, with benefits sustained or further improved over time.
In addition, retrospective U.S. claims data spanning three years showed lasting reductions in prescription pain medication use among adults with NF1-PN treated with Koselugo. These findings provide supportive real-world evidence for symptom improvement and reduced pain burden in this population.
Christophe Hotermans, Senior Vice President, Head of Global Medical Affairs, Alexion stated that the new PREVAIL and KOMET data reflect continued progress across the rare neurology portfolio, with gefurulimab reinforcing C5 inhibition in gMG and additional evidence highlighting Koselugo’s clinical impact in adults with NF1-PN.
Reference
Alexion data at 2026 AAN Annual Meeting reflects industry-leading portfolio and commitment to enhancing care across rare diseases, 10 April 2026, Alexion data at 2026 AAN Annual Meeting reflects industry-leading portfolio and commitment to enhancing care across rare diseases
Safety and Efficacy of ALXN1720 in Adults with Generalized Myasthenia Gravis, ClinicalTrials.gov ID NCT05556096, https://clinicaltrials.gov/study/NCT05556096
Efficacy and Safety of Selumetinib in Adults with NF1 Who Have Symptomatic, Inoperable Plexiform Neurofibromas (KOMET), ClinicalTrials.gov ID NCT04924608, https://clinicaltrials.gov/study/NCT04924608
About the Writer
Dr. Anuja Badgujar, BDS is a dentist with expertise in US healthcare data and medical data annotation. With four years of experience handling US healthcare datasets, she brings strong domain knowledge and precision to her work. She is also deeply passionate about medical writing, with a focus on translating complex medical information into clear and structured content.