Pediatric Phase 1/1b Study Of Entrectinib In Patients With Primary Brain Tumors, Neuroblastoma, And Ntrk, Ros1, Or Alk Fusions

AbstractThe STARTRK-NG (Studies of Tumor Alterations Responsive to Targeting Receptor Kinases - Next Generation) trial is a Phase 1/1b study of entrectinib in pediatric patients with cancer, including primary brain tumors, neuroblastoma, and other non-neuroblastoma, extracranial solid tumors harboring NTRK, ROS1, or ALK gene fusions (NCT02650401). Entrectinib is a potent oral, CNS-penetrant, inhibitor of the tyrosine kinases TRKA/B/C (encoded by the genes NTRK1/2/3, respectively), ROS1, and ALK with IC50s 10% incidence) treatment-related adverse events have been fatigue/asthenia, dysgeusia, paresthesia, nausea, myalgia, diarrhea, dizziness, arthralgia, vomiting, and constipation; importantly, there has been no evidence of cumulative toxicity. In addition, we have treated a 20-month-old boy presenting with infantile fibrosarcoma metastatic to the brain, which harbored an ETV6-NTRK3 fusion. Tumor restaging following 1 month of therapy showed a significant tumor regression of CNS metastases accompanied by significant clinical improvement. Together, these data provide compelling evidence to identify pediatric patients harboring NTRK, ROS1, or ALK fusions for enrollment in the STARTRK-NG trial.