SpringWorks gets an early second approval

SpringWorks’ attractiveness as an acquisition target has just increased, with FDA approval for the group’s second product, mirdametinib, coming over two weeks early. As hoped, the MEK inhibitor (now branded Gomekli) has got the green light in adults and children with symptomatic plexiform neurofibromas caused by the genetic condition neurofibromatosis type 1. This puts SpringWorks ahead of its NF1-PN rival, AstraZeneca, whose Koselugo is limited to children, who account for only around a quarter of the 40,000 US patients. Despite this Koselugu sold $631m in 2024. Evercore ISI’s Cory Kasimov reckons Gomekli could become a $1bn drug, helped by a better safety profile and a dispersible tablet, versus Koselugo’s harder-to-swallow capsule formation. Still, Koselugo’s use could soon expand, with Astra revealing last year that its phase 3 Komet study in adults met its primary endpoint, showing an ORR improvement versus placebo; data are being saved for a medical meeting. SpringWorks hasn’t disclosed the price for Gomekli, but Kasimov estimates that this will come in around $15,000 per month, in line with Koselugo. Gomekli should be available within two weeks. Merck KGaA this week confirmed its interest in buying SpringWorks; the latest approval was expected, but could embolden SpringWorks in seeking a higher price.

Cross-trial comparison of MEK inhibitors for NF1-PN

Note: CPK=creatine phosphokinase; NF1-PN=neurofibromatosis type 1-associated plexiform neurofibromas. Source: OncologyPipeline & product labels.