Alexion, AstraZeneca Rare Disease, announced that the European Commission has approved Koselugo (selumetinib) for the treatment of symptomatic, inoperable plexiform neurofibromas (PN) in adult patients with neurofibromatosis type 1 (NF1). Koselugo is an oral, selective MEK inhibitor and is the first and only approved treatment option for adults with this rare condition in the European Union.

The approval follows a positive opinion from the Committee for Medicinal Products for Human Use (CHMP) and is supported by results from KOMET, the largest and only placebo-controlled global Phase III trial conducted in this patient population. The findings, presented at the 2025 American Society of Clinical Oncology (ASCO) Annual Meeting and published in The Lancet, showed that Koselugo achieved a statistically significant objective response rate (ORR) of 20 per cent compared to 5 per cent with placebo by cycle 16.

Neurofibromatosis type 1 (NF1) is a rare, progressive genetic disorder usually diagnosed in early childhood and often continuing into adulthood. Up to half of individuals with NF1 develop plexiform neurofibromas, which are non-malignant tumours that can affect the brain, spinal cord, and peripheral nerves. These tumours can grow over time, leading to pain, disfigurement, and functional impairments, severely impacting quality of life.

Professor Pierre Wolkenstein, MD, PhD, Head of the Department of Dermatology at Henri Mondor Hospital, APHP, Paris East University (UPEC), and National Coordinating Investigator of the KOMET trial in Europe, commented:

“The approval of Koselugo for adults with NF1 PN in Europe provides an important new treatment option that bridges the gap beyond childhood. As demonstrated in the KOMET Phase III trial, adults treated with Koselugo experienced significant tumour volume reductions with a safety profile consistent with that observed in paediatric patients. This approval validates the clinical benefits of Koselugo for newly diagnosed adults and those transitioning from paediatric to adult care.”

Marc Dunoyer, Chief Executive Officer, Alexion, said: “This European Commission approval marks an important milestone for the NF1 community, extending the life-changing potential of Koselugo to adults and ensuring continuity of care into adulthood. It underscores our commitment to advancing innovative therapies that address unmet needs in rare diseases, and we are dedicated to making Koselugo available to adult patients across Europe as quickly as possible.”

Koselugo has also been recently approved in Japan and other countries for the treatment of adult patients with symptomatic, inoperable PN associated with NF1, based on the same KOMET Phase III data. Additional regulatory reviews are currently underway in other regions.