Koselugo significantly reduces neurofibromas in ongoing phase 3 study

An oral therapeutic significantly reduced the number of tumors in adults with neurofibromatosis type 1 who have symptomatic, inoperable plexiform neurofibromas, according to topline results from a phase 3 study.

The safety and efficacy of Koselugo (selumetinib, AstraZeneca/Merck) an oral, selective mitogen-activated protein kinase/extracellular signal-regulated kinase inhibitor, were examined in KOMET, a global, randomized, double-blind placebo-controlled multicenter clinical trial, Merck said in a release.

The study enrolled 146 adults from 13 countries who had the rare condition. They were randomly assigned 1:1 to receive either 10 mg or 25 mg oral capsules of Koselugo or placebo.

The primary outcome of the study was confirmed objective response rate, defined as the ratio of enrollees with complete or partial (at least 20% tumor volume reduction) response in reduction of plexiform neurofibromas vs. placebo over a 3-year span, according to the study’s website. The safety profile of Koselugo was consistent with previously conducted research in children and adolescents, with no new emergent safety signals.

“With limited options to manage [neurofibromatosis type 1 (NF1)] plexiform neurofibromas in adults, many patients experience functional impairment and symptoms, which can substantially impact their lives,” Ignacio Blanco Guillermo, MD, PhD, principal investigator of the KOMET trial, stated in the release, “These clinically meaningful data show Koselugo has the potential to make a positive impact in patient care by reducing the size of plexiform neurofibromas.”

Diagnosis of NF1 typically occurs in early childhood. Disease progression often extends into adulthood, with no currently approved treatments for adults, per the release.

“Adults with NF1 are in critical need of treatment options to help manage symptomatic, inoperable plexiform neurofibromas,” Scot Ebbinghaus, MD, vice president of global clinical development at Merck Research Laboratories, said in the release. “These positive results from the KOMET trial demonstrate the potential to expand the use of Koselugo beyond pediatric patients to also treat adult patients living with this rare and challenging genetic condition.”