FDA Approves Selumetinib in Pediatric Neurofibromatosis Type 1

Based on a relative bioavailability study in healthy adults and exposure matching between the pediatric patient populations in the phase 2 SPRINT Stratum I study and the SPRINKLE study, selumetinib is now approved for this pediatric NF1-PN population.

The FDA has approved selumetinib (Koselugo) granules and capsules for the treatment of pediatric patients who are 1 or older with neurofibromatosis type 1 (NF1) and symptomatic, inoperable plexiform neurofibromas (NF1-PNs), according to a release from the FDA.1

Previously, in April 2020, selumetinib capsules were approved for the treatment of pediatric patients 2 years of age and older with NF1-PNs.2

The approval was based on adequate bridging between the oral granule and approved capsule formulations in a relative bioavailability study in healthy adults (Study 89) and exposure matching between the pediatric patient populations in the SPRINT phase 2 Stratum 1 study (NCT01362803) and the SPRINKLE study (NCT05309668).

Notably, the similar exposure between formulations supported the extrapolation of efficacy from pediatric patients 2 years and older to patients 1 year and older.

The recommended dose of selumetinib, based on body surface area, is 25 mg/m2 orally twice daily until disease progression or unacceptable toxicity.

The prescribing information for selumetinib warns about cardiomyopathy, ocular toxicity, gastrointestinal toxicity, and skin toxicity, among other things.

References

1. FDA approves selumetinib for pediatric patients 1 year of age and older with neurofibromatosis type 1 with symptomatic, inoperable plexiform neurofibromas. FDA. September 10, 2025. Accessed September 10, 2025. https://tinyurl.com/5n7mrkzk
2. FDA approves selumetinib for neurofibromatosis type 1 with symptomatic, inoperable plexiform neurofibromas. FDA. April 10, 2020. Accessed September 10, 2025. https://tinyurl.com/5cars48a