FDA approves mirdametinib for patients 2 years, older with neurofibromatosis type 1

FDA approves mirdametinib for patients 2 years, older with neurofibromatosis type 1 | Image Credit: © Calin - © Calin - stock.adobe.com.

The FDA has approved mirdametinib (Gomekli; SpringWorks Therapeutics, Inc.), a kinase inhibitor, for adult and pediatric patients aged 2 years and older with neurofibromatosis type 1 (NF1) who have symptomatic plexiform neurofibromas (PN) not amenable to complete resection, according to a press release from SpringWorks Therapeutics.¹

The approval was based on efficacy and safety data from the ReNeu trial (NCT03962543), a multicenter, single-arm study that evaluated mirdametinib in 114 patients (58 adults, 56 pediatric patients) with symptomatic, inoperable NF1-associated PN causing significant morbidity.

The primary efficacy endpoint was the confirmed overall response rate (ORR), defined as the percentage of patients achieving either a complete response (disappearance of the target PN) or a partial response (≥20% reduction in PN volume), as determined by blinded independent central review via volumetric MRI analysis. The confirmed ORR was 41% in adult patients (95% CI: 29, 55) and 52% in pediatric patients (95% CI: 38, 65).

The most common adverse reactions (>25%) in adults included rash, diarrhea, nausea, musculoskeletal pain, vomiting, and fatigue. In pediatric patients, the most commonly reported adverse events (>25%) were rash, diarrhea, musculoskeletal pain, abdominal pain, vomiting, headache, paronychia, left ventricular dysfunction, and nausea. Grade 3 or 4 laboratory abnormalities occurring in more than 2% of patients included increased creatine phosphokinase in adults and both decreased neutrophil count and increased creatine phosphokinase in pediatric patients.

Mirdametinib carries risks of left ventricular dysfunction and ocular toxicities, including retinal vein occlusion, retinal pigment epithelial detachment, and blurred vision. Dose modifications, including treatment interruption, reduction, or discontinuation, should be considered based on severity.

The recommended dose of mirdametinib is based on body surface area. Full prescribing information will be available at Drugs@FDA.^1,2

References:

1. FDA approves mirdametinib for adult and pediatric patients with neurofibromatosis type 1 who have symptomatic plexiform neurofibromas not amenable to complete resection. FDA. Press release. February 11, 2025. Accessed February 11, 2025. https://www.fda.gov/drugs/resources-information-approved-drugs/fda-approves-mirdametinib-adult-and-pediatric-patients-neurofibromatosis-type-1-who-have-symptomatic

2. Drugs@FDA: FDA-Approved Drugs. Accessed February 11, 2025. https://www.accessdata.fda.gov/scripts/cder/daf/index.cfm