Long-term safety and efficacy of selumetinib in children with neurofibromatosis type 1 on a phase 1/2 trial for inoperable plexiform neurofibromas.

Background: Selumetinib shrank inoperable symptomatic plexiform neurofibromas (PN) in children with neurofibromatosis type 1 (NF1) and provided clinical benefit for many in our previously published phase 1/2 clinical trials (SPRINT, NCT01362803). At the data cutoff (DCO) of the prior publications, 65% of participants were still receiving treatment. This report presents up to 5 years of additional safety and efficacy data from these studies.