Health Canada Approves Koselugo for Adult Neurofibromatosis Type 1 Patients with Plexiform Neurofibromas
Key Insights
Health Canada has approved Koselugo (selumetinib) for adult patients with neurofibromatosis type 1 (search) who have symptomatic, inoperable plexiform neurofibromas (search), addressing a significant unmet medical need.
The approval was based on the KOMET Phase III trial, which demonstrated a statistically significant 20% objective response rate compared to 5% with placebo.
This marks the first treatment option for Canadian adults with this rare genetic condition, as Koselugo was previously only available for pediatric patients.
Health Canada has approved Koselugo (selumetinib) for the treatment of adult patients with neurofibromatosis type 1 (search) (NF1) who have symptomatic, inoperable plexiform neurofibromas (search) (PN), marking a significant milestone for patients with this rare genetic condition. The approval by Alexion, AstraZeneca Rare Disease, addresses a critical unmet medical need for Canadian adults living with NF1.
Clinical Trial Results Drive Approval
The regulatory approval was based on positive results from KOMET, described as the largest and only placebo-controlled global Phase III trial in this patient population. The study enrolled 145 adults from 13 countries across North America, South America, Europe, Asia and Australia, with participants' baseline characteristics reflective of the global adult NF1 patient population.
In the primary analysis, Koselugo demonstrated 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. The primary endpoint was confirmed objective response rate by cycle 16, defined as the percentage of patients with confirmed complete response (disappearance of PNs) or partial response (at least 20% reduction in tumour volume).
Addressing a Significant Care Gap
"Adults in Canada living with NF1 who have symptomatic, inoperable PN now have a meaningful treatment option beyond childhood," said Dr. Ryan Thomas, Family Physician at Scarborough Academic Family Health Centre and Clinical Associate at the Elisabeth Raab Neurofibromatosis Clinic, University Health Network, Toronto. "The approval of selumetinib addresses a significant care gap and offers new hope in this space."
The approval represents a major advancement for the patient community, as Gabrielle Labonté, General Manager of Association de la neurofibromatose du Québec, noted: "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."
Understanding NF1 and Plexiform Neurofibromas
NF1 is a rare, progressive, genetic condition caused by a spontaneous or inherited mutation in the NF1 gene, usually diagnosed in early childhood but often progressing into adulthood. The condition can impact every organ system and affects up to 50% of patients who may develop plexiform neurofibromas (search) on the nerve sheaths.
These PN can cause significant clinical issues including disfigurement, motor dysfunction, pain, airway dysfunction, visual impairment and bladder or bowel dysfunction. The tumours 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.
Mechanism of Action and Safety Profile
Koselugo is a kinase inhibitor that blocks specific enzymes (MEK1 (search) and MEK2 (search)) involved in stimulating cell growth. In NF1, these enzymes are overactive, causing tumour cells to grow in an unregulated way, creating plexiform neurofibromas (search). By blocking these enzymes, Koselugo slows down the growth of tumour cells and therefore PN growth.
The safety profile of Koselugo in the KOMET Phase III trial was consistent with its known profile and established use in pediatric patients. The drug has been granted Orphan Drug Designation in the US, EU, Japan and other countries for the treatment of NF1.
Global Regulatory Status and Market Access
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, with additional regulatory reviews ongoing. The drug was previously approved in these regions for certain pediatric patients with the same condition.
"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," said Karen Heim, Vice President and General Manager, Alexion Canada. "With this approval, both children and adults living with NF1 PN now have a treatment option available to them in Canada."