The US Food and Drug Administration (FDA) has approved SpringWorks Therapeutics’ Gomekli (mirdametinib) to treat neurofibromatosis type 1 (NF1), a rare genetic disorder affecting approximately 100,000 people in the US.
The drug has been specifically authorised to treat adult and paediatric patients aged two years and older who have symptomatic plexiform neurofibromas (PN) that cannot be removed surgically.
NF1 causes a variety of symptoms across multiple organ systems, including abnormal pigmentation, skeletal deformities, tumour growth and neurological complications.
Around 40,000 NF1 patients in the US have PNs, which are tumours that grow along the peripheral nerve sheath and can cause severe disfigurement, pain and functional impairment. PNs can also develop into malignant peripheral nerve sheath tumours, an aggressive and potentially fatal disease.
SpringWorks’ Gomekli is an oral small molecule MEK inhibitor and the first and only FDA-approved therapy for both adults and children with NF1-PN.
The FDA’s decision on the drug was supported by results from the phased 2b ReNeu trial, which demonstrated an objective response rate of 41% and 52% in adult and paediatric NF1-PN patients, respectively.
Tumour volume reductions were deep and durable, SpringWorks said, with 50% of adults and 48% of children in response for at least 24 months, and patients in both cohorts also experienced early and sustained improvements in pain and quality of life.
SpringWorks’ chief executive officer, Saqib Islam, said: “The NF1-PN patient community has a great need for more treatment options. With [this] approval, we are honoured to serve both adults and children with NF1-PN and provide them with a therapy that has the potential to shrink their tumours and offer meaningful symptomatic relief.”
Alongside the approval, the FDA has awarded SpringWorks a priority review voucher (PRV), which the company can redeem to have any drug reviewed under the regulator’s priority review pathway.
Under the PRV programme, which was created to encourage the development of new drug and biological products for the prevention and treatment of certain rare paediatric diseases, SpringWorks may also sell or transfer the voucher to another company.