Selumetinib for children with neurofibromatosis type 1 and plexiform neurofibromas that can't be removed by surgery, and impact on how the condition affects caregivers: a plain language summary.

What Is This Summary About?: Neurofibromatosis type 1 (also called NF1) is a rare genetic condition. It causes a range of symptoms that develop from childhood onwards and worsen over time. Some children with NF1 develop non-cancerous nerve tumors called plexiform neurofibromas. Plexiform neurofibromas can grow large and compress nearby tissues. This can cause severe pain, reduced movement, vision and hearing loss, and other medical problems. Some children can have plexiform neurofibromas removed surgically. Most children have tumors that cannot be removed by surgery (known as inoperable tumors). Children with inoperable plexiform neurofibromas can receive a medicine called selumetinib. This plain language summary includes important findings from two selumetinib studies in children with NF1 and inoperable plexiform neurofibromas: The SPRINT selumetinib studies are part of a clinical study program that looked at how well selumetinib works in treating children with symptomatic, inoperable plexiform neurofibromas. The SPRINT studies program included the first studies of this medicine done in children, called phase 1 and phase 2 studies. For the phase 2 study, some children had severe symptoms and some children did not. The group of children with severe symptoms is called group 1, and their results are included in this summary. The researchers monitored the participating children for up to 5 years in a long-term study to better understand how the treatment works over time. The NF1 caregivers experience study is a related study where caregivers shared their experiences of caring for children with NF1and plexiform neurofibromas.

What Were The Results?: A total of 74 children took part in the SPRINT phase 1 and phase 2 (group 1) study. Their ages ranged from 3 to 18.5 years, and their average age was 10.3 years. After more than 4 years of treatment, around 70% of the children (52 out of 74) had smaller tumors. For most children, the responses lasted beyond 1 year. There was a significant and lasting reduction in the intensity of the children';s tumor pain, noticeable as early as 2 months after starting the treatment. After 12 months, children reported their pain dropped from an average score of 2.2 to 0.6 and stayed low at 0.58 over 4 years. There was also an improvement in how much their pain affected the children's ability to do daily tasks. Some children had side effects related to selumetinib, although these were generally manageable. Results from the NF1 caregivers experience study showed caregivers of children with plexiform neurofibromas face significant impacts in physical, psychological, economic, and social aspects. These effects often result in a loss of productivity and difficulties with daily activity.

What Do The Results Of The Study Mean?: Children with NF1 who have symptomatic, inoperable plexiform neurofibromas can benefit from selumetinib treatment. Selumetinib is generally well-tolerated, but it is important to monitor side effects during treatment. Caring for a child with NF1 and symptomatic, inoperable plexiform neurofibromas has a significant impact on family members and others providing daily care. This highlights the importance of improving treatment and quality of life for both children with the condition and their caregivers.