Mirdametinib Shows Durable Response in NF1-Associated Plexiform Neurofibromas
Key Clinical Takeaways
- Mirdametinib demonstrated confirmed objective response rates of 47% in adults and 55% in children with NF1-associated plexiform neurofibromas, with many responders achieving deep responses (>50% volume reduction).
- Best median tumor volume change was –41% in adults and –43% in children; median duration of response remains unreached, indicating sustained benefit with extended treatment.
- The long-term safety profile was consistent and manageable: common TRAEs included dermatitis acneiform, diarrhea, nausea, vomiting (adults) and diarrhea, dermatitis acneiform, paronychia (children); grade ≥3 TRAEs occurred in 17% of adults and 25% of children, with discontinuation due to TRAEs in 22% of adults and 9% of children.
Angela Hirbe, MD, PhD, Washington University, St. Louis, Missouri, discusses long-term follow-up results from the phase 2b ReNeu trial showing that mirdametinib demonstrates durable and deep volumetric responses in adult and pediatric patients with neurofibromatosis type 1 (NF1)-associated plexiform neurofibromas not amenable to complete resection.
Confirmed objective response rate was 47% in adult patients and 55% in pediatric patients, with many responders achieving >50% tumor volume reductions and median duration of response not reached. The safety profile remained manageable with no new signals during long-term follow-up.
These findings were presented at the 2025 Society for Neuro-Oncology (SNO) Annual Meeting in Honolulu, Hawaii.
Source:
Hirbe A, Moertel C, Shuhaiber H, et al. Update from the long-term follow-up (LTFU) phase of ReNeu: A pivotal phase 2b trial of mirdametinib in children and adults with neurofibromatosis type 1 (NF1)-associated symptomatic plexiform neurofibroma (PN). Presented at the SNO Annual Meeting. November 19 - 23, 2025; Honolulu, Hawaii. Abstract CTNI-06.
