SpringWorks Therapeutics Receives Positive CHMP Opinion for Mirdametinib for the Treatment of Adult and Pediatric Patients with NF1-PN

Company Overview - SpringWorks Therapeutics, Inc. is a commercial-stage biopharmaceutical company focused on severe rare diseases and cancer, with a commitment to improving the lives of patients [7] - The company has developed the first and only FDA-approved medicine for both adults and children with neurofibromatosis type 1 associated plexiform neurofibromas (NF1-PN) [7] Product Development - Mirdametinib, a MEK inhibitor, has received a positive opinion from the European Medicines Agency's Committee for Medicinal Products for Human Use (CHMP) for conditional marketing authorization in the EU for treating symptomatic, inoperable plexiform neurofibromas in patients aged 2 years and older with NF1 [1][2] - The European Commission is expected to make a final decision regarding mirdametinib's approval in the third quarter of 2025 [1] Clinical Trial Results - The positive opinion was based on the Marketing Authorization Application (MAA) validated by the EMA in August 2024, which included results from the Phase 2b ReNeu trial involving 114 patients [2][4] - The trial demonstrated a confirmed objective response rate (ORR) of 41% in adults and 52% in children, with significant reductions in target tumor volume [2][4] - Among patients with confirmed responses, 88% of adults and 90% of children had responses lasting at least 12 months [2] Patient Demographics and Disease Impact - Neurofibromatosis type 1 (NF1) affects approximately 3 in 10,000 people in the EU, translating to an estimated 135,000 individuals [2][5] - Patients with NF1 have a 30% to 50% lifetime risk of developing plexiform neurofibromas, which can lead to severe disfigurement, pain, and functional impairment [2][5] Safety Profile - Mirdametinib has shown a manageable safety and tolerability profile, with common adverse events in adults including rash, diarrhea, and nausea, while children experienced similar side effects along with additional issues like left ventricular dysfunction [2][6]