Approval based on KOMET Phase III trial results which showed 20% objective response rate in tumour size reduction
MISSISSAUGA, ON, March 9, 2026 /CNW/ - Alexion, AstraZeneca Rare Disease's Koselugo (selumetinib), an oral, selective MEK inhibitor, has been approved in Canada for the treatment of adult patients with neurofibromatosis type 1 (NF1) who have symptomatic, inoperable plexiform neurofibromas (PN).1
The approval by Health Canada was based on positive results from KOMET, the largest and only placebo-controlled global Phase III trial in this patient population. Data were presented at the 2025 American Society of Clinical Oncology (ASCO) Annual Meeting and published in The Lancet.2
NF1 is a rare, progressive, genetic condition usually diagnosed in early childhood, but often progressing into adulthood, that can impact every organ system.3,4 Up to 50% of people living with NF1 may develop a type of non-malignant tumour called PN that may affect the brain, spinal cord and nerves.4,5 PN may appear later in a person's life and can grow and become large, leading to pain, disfigurement and muscle weakness, among other debilitating symptoms.4,5
Ryan Thomas, MD, Family Physician, Scarborough Academic Family Health Centre, and Clinical Associate at the Elisabeth Raab Neurofibromatosis Clinic, University Health Network, Toronto, said: "Adults in Canada living with NF1 who have symptomatic, inoperable PN now have a meaningful treatment option beyond childhood. The approval of selumetinib addresses a significant care gap and offers new hope in this space."
Sarah Lapointe, MD, Associate Professor, Department of Neuroscience at Université de Montréal, and Neuro-Oncologist, Centre Hospitalier de l'Université de Montréal (CHUM), said: "Clinicians caring for adults with NF1 have long faced the limits of supportive care for plexiform neurofibromas, which can cause severe pain, reduced mobility and major functional impact. As the first systemic therapy with proven ability to slow PN growth, selumetinib represents a transformative innovation for patients. This approval offers real hope for improved symptom control and better quality of life for adults in Canada who have historically had very limited therapeutic options."
Desirée Sher, Executive Director, Tumour Foundation of BC, said: "Health Canada's approval of selumetinib for adults represents an important step forward, offering an effective treatment option to individuals living with symptomatic, inoperable plexiform neurofibromas. We welcome this milestone and the hope it brings for adults in the NF1 community who have waited many years to see meaningful progress in the management of their condition."
Gabrielle Labonté, General Manager, Association de la neurofibromatose du Québec, said: "The approval of selumetinib for adults living with NF1 represents a major advancement for the Quebec community and addresses a critical unmet need among adults affected by this condition. This treatment, already used in children, has long generated significant impact within the community, and its approval for adults has been eagerly anticipated. This milestone marks an important advance in care and has the potential to contribute to an enhanced quality of life for adults living with NF1."
Karen Heim, Vice President and General Manager, Alexion Canada, said: "Alexion is committed to bringing innovative medicines to patients with unmet need. With this approval, both children and adults living with NF1 PN now have a treatment option available to them in Canada. Koselugo was recently listed on the common drug list under the National Strategy for Drugs for Rare Disease, which is a testament to its impact on those living with this rare disease."
In the primary analysis of the trial, Koselugo showed a statistically significant objective response rate (ORR) of 20% (n=14/71, 95% CI: 11.2, 30.9) compared to 5% with placebo (n=4/74, 95% CI: 1.5, 13.3; p=0.01) by cycle 16. After 12 cycles, patients on placebo were switched to Koselugo and patients on Koselugo remained on treatment for an additional 12 cycles.2
The safety profile of Koselugo in the KOMET Phase III trial was consistent with its known profile and established use in paediatric patients.2
Koselugo has been recently approved in the US, EU, Japan and other countries for the treatment of adult patients with NF1 who have symptomatic, inoperable PN based on data from the KOMET Phase III trial, and additional regulatory reviews are ongoing.
For important safety information, please consult the Koselugo Product Monograph.
Notes
NF1
NF1 is a rare, progressive, genetic condition that is caused by a spontaneous or inherited mutation in the NF1 gene.3,4 NF1 is associated with a variety of symptoms, including soft lumps on and under the skin (cutaneous neurofibromas) and, in up to 50% of patients, tumours called plexiform neurofibromas (PN) may develop on the nerve sheaths.4,5 These PN can cause clinical issues such as disfigurement, motor dysfunction, pain, airway dysfunction, visual impairment and bladder or bowel dysfunction.4,5
KOMET
KOMET is a global Phase III randomized, double-blind, placebo-controlled, multicentre trial designed to evaluate the efficacy and safety of Koselugo in adults with NF1 who have symptomatic, inoperable PN. The trial enrolled 145 adults from 13 countries across North America, South America, Europe, Asia and Australia, with participants' baseline characteristics, including gender and distribution of PN, reflective of the global adult NF1 patient population. Patients were enrolled and randomized to receive Koselugo or placebo (1:1) for 12 28-day cycles. Participants were required to have diagnosis of NF1, at least one symptomatic, inoperable PN measurable by volumetric MRI analysis, chronic PN pain score documented during screening, adequate organ and marrow function and stable chronic PN pain medication use at enrolment.2,6
The primary endpoint is confirmed objective response rate (ORR) by cycle 16 as assessed by ICR. ORR is defined as the percentage of patients with confirmed complete response (disappearance of PNs) or partial response (at least 20% reduction in tumour volume). Secondary endpoints include improved PN-related pain and health-related quality of life (HRQoL) at cycle 12.2,6
After 12 cycles, patients on placebo were switched to Koselugo and patients on Koselugo remained on treatment for an additional 12 cycles. Patients who had the opportunity to complete 24 cycles of treatment have the option to participate in a long-term extension period and continue to receive Koselugo.2,6
Koselugo
Koselugo (selumetinib) is a kinase inhibitor that blocks specific enzymes (MEK1 and MEK2), which are involved in stimulating cells to grow. In NF1, these enzymes are overactive, causing tumour cells to grow in an unregulated way creating so-called plexiform neurofibromas (PN). By blocking these enzymes, Koselugo slows down the growth of tumour cells and, therefore, the PN growth.
Koselugo is approved in the US, EU, Japan, China and other countries for the treatment of certain paediatric patients with NF1 who have symptomatic, inoperable PN.
Koselugo is approved in the US, EU, Japan and other countries for the treatment of adult patients with NF1 who have symptomatic, inoperable PN, and additional regulatory reviews are ongoing.
Koselugo has been granted Orphan Drug Designation in the US, EU, Japan and other countries for the treatment of NF1.
Alexion
Alexion, AstraZeneca Rare Disease, is focused on serving patients and families affected by rare diseases and devastating conditions through the discovery, development and delivery of life-changing medicines. A pioneering leader in rare disease for more than three decades, Alexion was the first to translate the complex biology of the complement system into transformative medicines, and today it continues to build a diversified pipeline across disease areas with significant unmet need, using an array of innovative modalities. As part of AstraZeneca, Alexion is continually expanding its global geographic footprint to serve more rare disease patients around the world. It is headquartered in Boston, US.
AstraZeneca
AstraZeneca (LSE/STO/NYSE: AZN) is a global, science-led biopharmaceutical company that focuses on the discovery, development, and commercialization of prescription medicines in Oncology, Rare Diseases, and BioPharmaceuticals, including Cardiovascular, Renal & Metabolism, and Respiratory & Immunology. Based in Cambridge, UK, AstraZeneca's innovative medicines are sold in more than 125 countries and used by millions of patients worldwide. Please visit astrazeneca.com and follow the Company on Social Media @AstraZeneca.
References
- Koselugo (selumetinib) Health Canada approved product monograph; March 2026.
- Chen, AP, et al. KOMET: a phase 3, multicentre, international, randomized, placebo-controlled study to assess the efficacy and safety of selumetinib in adults with neurofibromatosis type 1 and symptomatic, inoperable plexiform neurofibromas. The Lancet. 2025;405(10496):2217-2230.
- Tamura R. Current understanding of neurofibromatosis type 1, 2, and schwannomatosis. Int J Mol Sci. 2021;22(11):5850.
- Hirbe AC, et al. Neurofibromatosis type 1: a multidisciplinary approach to care. Lancet Neurol. 2014;13:834-843.
- Bergqvist C, et al. Neurofibromatosis 1 French national guidelines based on an extensive literature review since 1966. Orphanet J Rare Dis. 2020;15(1):37.
- ClinicalTrials.gov. Efficacy and safety of selumetinib in adults with NF1 who have symptomatic, inoperable plexiform neurofibromas (KOMET). NCT Identifier: NCT04924608. Available here. Accessed March 2026.
SOURCE AstraZeneca
