On September 10, 2025, the Food and Drug Administration approved selumetinib (KOSELUGO, AstraZeneca Pharmaceuticals LP) granules and capsules for pediatric patients 1 year of age and older with neurofibromatosis type 1 (NF1) who have symptomatic, inoperable plexiform neurofibromas (PN). FDA previously approved selumetinib capsules for pediatric patients 2 years of age and older with NF1 who have symptomatic, inoperable PN.

Full prescribing information for KOSELUGO will be posted on Drugs@FDA.

The approval was based on adequate bridging between the oral granule and approved capsule formulations in a relative bioavailability (BA) study in healthy adults (Study 89) and exposure matching between the pediatric patient populations in the SPRINT Phase II Stratum I study (capsule formulation, ≥ 2 years of age) and the SPRINKLE study (oral granule formulation, ≥ 1 year of age). Similar exposure between the formulations supports extrapolation of efficacy from pediatric patients ≥ 2 years of age to ≥ 1 year of age.

The selumetinib prescribing information includes warnings and precautions for cardiomyopathy, ocular toxicity, gastrointestinal toxicity, skin toxicity, increased creatine phosphokinase, increased levels of vitamin E and increased bleeding risk (KOSELUGO capsules), and embryo-fetal toxicity. The incidences of warnings and precautions were updated to include data from a larger number of pediatric patients; no new safety signals were identified.

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

Selumetinib received breakthrough therapy and orphan drug designations. FDA expedited programs are described in the Guidance for Industry: Expedited Programs for Serious Conditions-Drugs and Biologics.

Healthcare professionals should report all serious adverse events suspected to be associated with the use of any medicine and device to FDA’s MedWatch Reporting System or by calling 1-800-FDA-1088.

For assistance with single-patient INDs for investigational oncology products, healthcare professionals may contact OCE’s Project Facilitateat240-402-0004 or email OncProjectFacilitate@fda.hhs.gov.

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