Selumetinib
Selumetinib is a targeted cancer medication that inhibits MEK1/2 kinases, which are key components of the RAS-RAF-MEK-ERK signaling pathway involved in cell growth and proliferation. It is primarily used to treat inoperable plexiform neurofibromas in pediatric patients with neurofibromatosis type 1 (NF1). By blocking this pathway, selumetinib helps reduce tumor size and associated symptoms in these patients.
Selumetinib is a MEK inhibitor used to treat inoperable plexiform neurofibromas in children with NF1 by blocking cell growth signaling pathways.
Key facts at a glance
- ATC
- L01EE04
- RxNorm
- 2289380
- Generic
- Selumetinib
- Class
- atc-l01
- Brands
- Koselugo
- Availability
- rx
- Lactation
- unknown
- Routes
- oral
- Forms
- capsule
- Regions
- US, EU, CN, JP
- Monitoring
- —
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Do not use this information to diagnose yourself or to replace a physician's advice. Always consult a qualified healthcare provider before starting, stopping, or changing any medication. If you believe you are experiencing a medical emergency, call your local emergency number immediately.
Treatment of symptomatic, inoperable plexiform neurofibromas in pediatric patients with neurofibromatosis type 1 (NF1). It is specifically indicated for patients with NF1 who have plexiform neurofibromas that cause significant morbidity and cannot be surgically removed.
Selumetinib is a selective MEK1/2 inhibitor that blocks the mitogen-activated protein kinase (MAPK) pathway. By inhibiting MEK1 and MEK2 kinases, it prevents phosphorylation and activation of ERK, disrupting the RAS-RAF-MEK-ERK cascade that drives abnormal cell growth in NF1-associated tumors.
Common side effects include skin rash, diarrhea, nausea, vomiting, and elevated creatine phosphokinase levels. Patients should be monitored for cardiac events and ocular toxicity. Selumetinib is typically taken orally twice daily and should be swallowed whole with water. Treatment should be conducted by physicians experienced in managing NF1 and its complications.
Official drug label
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This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed July 26, 2026. · Read our editorial policy