SpringWorks' innovative oral MEK inhibitor, which was introduced from Pfizer (PFE.US), has been approved by the FDA.

On February 11, SpringWorks Therapeutics announced that the U.S. FDA has approved its MEK inhibitor Gomekli (mirdametinib) for the treatment of symptomatic plexiform neurofibromatosis (PN) in adults and children aged 2 years and older with neurofibromatosis type 1 (NF1) who have PN that cannot be completely removed. This is the first and only approved drug for the treatment of NF1-PN in adults and children.

The approval was based on the results of the Phase IIb ReNeu trial, which enrolled 114 patients with NF1-PN aged 2 years and older (58 adults and 56 pediatric patients). The data showed that Gomekli met the primary endpoint of objective response rate (ORR), with an ORR of 41% (24/58) in adult patients and 52% (29/56) in pediatric patients. Tumor volumes were significantly reduced and durable in treated patients; the median best percentage change in target PN volume was -41% in adult patients and -42% in pediatric patients.

Relief was durable in 88% of adult patients and 90% of pediatric patients for at least 12 months; in addition, 50% of adult patients and 48% of pediatric patients had relief for at least 24 months. Pain and quality of life also improved significantly from baseline, as assessed by multiple patient-reported outcome tools in both groups.