On July 1, 2024 SpringWorks Therapeutics, Inc. (Nasdaq: SWTX), a commercial-stage biopharmaceutical company focused on severe rare diseases and cancer, reported that the Company has completed the submission of a New Drug Application (NDA) to the U.S. Food and Drug Administration (FDA) for mirdametinib, an investigational MEK inhibitor, for the treatment of pediatric and adult patients with neurofibromatosis type 1- associated plexiform neurofibromas (NF1-PN) (Press release, SpringWorks Therapeutics, JUL 1, 2024, View Source [SID1234644625]).
Schedule your 30 min Free 1stOncology Demo!
Discover why more than 1,500 members use 1stOncology™ to excel in:
Early/Late Stage Pipeline Development - Target Scouting - Clinical Biomarkers - Indication Selection & Expansion - BD&L Contacts - Conference Reports - Combinatorial Drug Settings - Companion Diagnostics - Drug Repositioning - First-in-class Analysis - Competitive Analysis - Deals & Licensing
Schedule Your 30 min Free Demo!
"We are pleased to be one step closer towards our goal of bringing mirdametinib to patients with NF1-PN in the U.S. and believe that our ReNeu data support the potential for mirdametinib to be a differentiated and best-in-class therapy for both children and adults living with this devastating disease," said Saqib Islam, Chief Executive Officer of SpringWorks. "We look forward to working closely with the FDA throughout the review process and also plan to file for regulatory approval in the European Union later this year."
The NDA submission includes data from the pivotal Phase 2b ReNeu trial, which evaluated mirdametinib in patients ≥ 2 years of age with NF1-associated PN causing significant morbidity. Results were presented in an oral presentation at the 2024 American Society of Clinical Oncology (ASCO) (Free ASCO Whitepaper) Annual Meeting and demonstrated that mirdametinib treatment resulted in significant objective response rates confirmed by blinded independent central review, deep and durable responses, improvement in pain and health-related quality of life as well as a manageable safety profile across both the adult and pediatric cohorts.1
The FDA and the European Commission have granted Orphan Drug designation for mirdametinib for the treatment of NF1. The FDA has also granted Fast Track designation for the treatment of patients ≥ 2 years of age with NF1-PN that are progressing or causing significant morbidity and Rare Pediatric Disease designation for the treatment of NF1.
In the second half of 2024, SpringWorks also plans to file a Marketing Authorization Application (MAA) with the European Medicines Agency (EMA) for mirdametinib for the treatment of children and adults with NF1-PN.
About the ReNeu Trial
ReNeu (NCT03962543) is an ongoing, multi-center, open-label Phase 2b trial evaluating the efficacy, safety, and tolerability of mirdametinib in patients ≥ 2 years of age with an inoperable NF1-associated PN causing significant morbidity. The study enrolled 114 patients to receive mirdametinib at a dose of 2 mg/m2 twice daily (maximum dose of 4 mg twice daily) without regard to food. Mirdametinib was administered orally in a 3-week on, 1-week off dosing schedule as either a capsule or dispersible tablet. The primary endpoint is confirmed objective response rate defined as ≥ 20% reduction in target tumor volume during the 24 cycle treatment phase, as measured by MRI and assessed by blinded independent central review. Secondary endpoints include safety and tolerability, duration of response, and changes from baseline in patient reported outcomes to Cycle 13. The treatment phase of the trial is complete and results were presented at the 2024 American Society of Clinical Oncology (ASCO) (Free ASCO Whitepaper) Annual Meeting. Patients who completed the treatment phase were eligible to continue receiving treatment in the optional long-term follow up portion of the study, which is ongoing.
About NF1-PN
Neurofibromatosis type 1 (NF1) is a rare genetic disorder that arises from mutations in the NF1 gene, which encodes for neurofibromin, a key suppressor of the MAPK pathway.2,3 NF1 is the most common form of neurofibromatosis, with an estimated global birth incidence of approximately 1 in 2,500 individuals, and approximately 100,000 patients living with NF1 in the United States.4,5 The clinical course of NF1 is heterogeneous and manifests in a variety of symptoms across numerous organ systems, including abnormal pigmentation, skeletal deformities, tumor growth and neurological complications, such as cognitive impairment.6 Patients with NF1 have an 8 to 15-year mean reduction in their life expectancy compared to the general population.3
NF1 patients have approximately a 30-50% lifetime risk of developing plexiform neurofibromas, or PN, which are tumors that grow in an infiltrative pattern along the peripheral nerve sheath and that can cause severe disfigurement, pain and functional impairment; in rare cases, NF1-PN may be fatal.7,8 NF1-PNs are most often diagnosed in the first two decades of life.7 These tumors can be aggressive and are associated with clinically significant morbidities; typically, they grow more rapidly during childhood.9,10
Surgical removal of these tumors is challenging due to the infiltrative tumor growth pattern along nerves and can lead to permanent nerve damage and disfigurement.11 MEK inhibitors have emerged as a validated class of treatment for NF1-PN.12
About Mirdametinib
Mirdametinib is a potent, oral, CNS-penetrant, allosteric small molecule MEK inhibitor in development as a monotherapy treatment for neurofibromatosis type 1-associated plexiform neurofibromas (NF1-PN) and low-grade glioma (LGG), and as a combination therapy for the treatment of several subsets of biomarker-defined metastatic solid tumors. Mirdametinib is an investigational drug for which safety and efficacy have not been established.
Mirdametinib is designed to inhibit MEK1 and MEK2, which occupy pivotal positions in the MAPK pathway. The MAPK pathway is a key signaling network that regulates cell growth and survival and plays a central role in multiple cancers and rare diseases when genetically altered.
The FDA and the European Commission have granted Orphan Drug designation for mirdametinib for the treatment of NF1. The FDA has also granted Fast Track designation for the treatment of patients ≥ 2 years of age with NF1-PN that are progressing or causing significant morbidity and Rare Pediatric Disease designation for the treatment of NF1.