Koselugo approved in Japan for paediatric patients with plexiform neurofibromas in neurofibromatosis type 1
Koselugo (selumetinib) has been approved in Japan for the treatment of paediatric patients three years of age and older with plexiform neurofibromas (PNs) in neurofibromatosis type 1 (NF1) with clinical symptoms, such as pain and disfigurement, and PNs which cannot be completely removed by surgery without risk of substantial morbidity.
The approval by the Japanese Ministry of Health, Labour and Welfare (MHLW) is based on positive results from the SPRINT Stratum 1 Phase II trial sponsored by the National Institutes of Health’s National Cancer Institute (NCI) Cancer Therapy Evaluation Program (CTEP). The trial showed Koselugo, an oral treatment option, reduced the size of inoperable tumours in children. Additionally, a Phase I trial in Japanese paediatric NF1 patients with symptomatic and inoperable PNs was also evaluated as a basis for the approval, with the trial showing tumour reduction.
NF1 is a debilitating genetic condition affecting one in 3,000 individuals worldwide, most commonly diagnosed in children under 10. In 30-50% of patients, tumours develop on the nerve sheaths (plexiform neurofibromas) and can cause clinical issues such as disfigurement, motor dysfunction, pain, airway dysfunction, visual impairment and bladder or bowel dysfunction.
Professor Yoshihiro Nishida, MD, PhD, Department of Rehabilitation Medicine at Nagoya University, Nagoya, Japan, and Japan Phase I trial investigator said: “People living with plexiform neurofibromas caused by neurofibromatosis type 1 often face painful physical, emotional and social burdens. This approval marks a major step forward in addressing the debilitating impact these plexiform neurofibromas have on paediatric patients living with neurofibromatosis type 1 in Japan. Koselugo provides a suitable intervention to treat symptomatic plexiform neurofibromas, which may improve long-term patient activities of daily living and quality of life.”
Marc Dunoyer, Chief Executive Officer, Alexion, said: “As the first medicine approved in Japan for paediatric patients with symptomatic, inoperable plexiform neurofibromas in neurofibromatosis type 1, Koselugo offers new hope for patients and families affected by this incurable genetic disease, whose only previous treatment option was repeated surgery. This approval is a testament to our longstanding commitment to rare disease research and we are energised by the opportunity to further accelerate innovation and care for the neurofibromatosis type 1 community.”
The SPRINT Stratum 1 Phase II trial showed Koselugo demonstrated an objective response rate (ORR) of 66% (33 of 50 patients, confirmed partial responses) in paediatric patients with PNs in NF1 when treated with Koselugo as twice-daily oral monotherapy. ORR is defined as the percentage of patients with confirmed complete (disappearance of PNs) or partial response (at least 20% reduction in tumour volume). The most common adverse reactions in the SPRINT trial were vomiting, blood creatine phosphokinase increase, diarrhoea and nausea.
Results from the SPRINT Stratum 1 Phase II trial were published online in The New England Journal of Medicine.2
In addition to Japan, Koselugo is also approved in the US and EU for the treatment of paediatric patients with NF1 and symptomatic, inoperable PNs. Further regulatory submissions are underway.