Pune, India | November 21, 2025
In a landmark decision, the U.S. Food and Drug Administration approved Koselugo (selumetinib) for adult patients with neurofibromatosis type 1 (NF1) who develop symptomatic, inoperable plexiform neurofibromas (PN). This new approval expands its previous pediatric indication, representing a major advancement for adults facing limited therapeutic options.
The FDA based this approval on results from the KOMET trial. A global, randomized, double-blind, placebo-controlled Phase III study including 145 adult NF1 patients with inoperable PN. After 16 treatment cycles, the confirmed overall response rate reached 20% in the selumetinib group. That compared with only 5% in the placebo group, demonstrating a clear and measurable clinical benefit.
Importantly, 86% of patients who responded maintained tumor reduction for at least six months, indicating durable treatment effects. Patients received oral dosing twice daily, adjusted based on body surface area, ensuring personalized therapy for each individual.
Neurofibromatosis type 1 is a rare genetic disorder often diagnosed during childhood, which can persist into adulthood and frequently leads to plexiform neurofibromas. These benign nerve-sheath tumors may cause pain, disfigurement, and functional impairment when large or inoperable, significantly affecting patients’ daily lives. Up to 50% of individuals with NF1 develop PN, highlighting an urgent need for effective therapies.
Experts hailed the FDA’s decision as a breakthrough, emphasizing that Koselugo finally provides adults with a long-awaited treatment option. The therapy addresses symptoms of progressive, debilitating PN and improves quality of life, while bridging an important treatment gap between pediatric and adult patients.
Industry leaders also welcomed the approval because it complements the current pediatric formulation. It also ensures continuity of care across all ages. Consequently, children transitioning into adulthood can continue treatment without interruption, which may lead to more predictable long-term outcomes.
Patient advocacy organizations praised the decision, noting that adults previously had very few therapeutic options. Many individuals lived with worsening symptoms and restricted mobility, so Koselugo now offers hope for meaningful symptom management and improved daily function.
Although its safety profile matches previous findings, physicians must monitor certain risks, including cardiovascular dysfunction, ocular toxicity, gastrointestinal effects, elevated creatine phosphokinase, bleeding, and potential embryo-fetal toxicity. Providers are encouraged to conduct regular cardiovascular and ophthalmic monitoring. It is especially for patients with preexisting conditions, allowing early detection of complications and safer ongoing therapy.
With the FDA approval, Koselugo now provides treatment for NF1-related PN in both pediatric and adult populations within the U.S. That giving patients previously left without options a critical therapy. This milestone reflects growing attention to rare diseases and underscores the need to improve care for underserved populations.
Internationally, the European Medicines Agency also recommended expanding Koselugo’s adult indication, which the European Commission subsequently approved. These steps highlight increasing recognition of the therapy’s value for adult NF1 patients, establishing global momentum for access to this treatment.
In conclusion, the FDA’s approval of Koselugo for adults with symptomatic, inoperable plexiform neurofibromas represents a significant medical breakthrough. The therapy provides an effective and safe treatment for adults while aligning with pediatric care, ultimately offering hope for improved quality of life and enhanced long-term disease management.
