Ewings Sarcoma Treatment, CLR 131, Granted Rare Pediatric Disease Designation

Cellectar Biosciences’ CLR 131 was granted a rare pediatric disease designation by the US Food and Drug Administration (FDA) this morning, August 13, 2018, for the treatment of Ewing’s sarcoma, a rare pediatric bone cancer.

“We are delighted to announce receipt of our third RPDD from the FDA, which underscores Cellectar’s commitment to rare pediatric cancers. There is a critical need to develop new therapies to fight deadly childhood cancers such as Ewing’s sarcoma, and CLR 131 has shown early promise in this arena,” said John Friend, MD, chief medical officer of Cellectar Biosciences, in a recent statement.

Plans for a phase 1 trial are currently underway to evaluate CLR 131 for the treatment of Ewing’s sarcoma, rhabdomyosarcoma, osteosarcoma, neuroblastoma, high-grade glioma, and lymphomas. An accelerated phase 1 trial designed to evaluate the safety, tolerability, pharmacokinetics, and pharmacodynamics of CLR 131 in pediatric patients with these cancer types has been granted clearance by the FDA.

The number of participants with dose limiting toxicities (DLT), which will be assessed by physical examination, vital signs, and laboratory values as measured in the timeframe of 85 days, will serve as the primary outcome measure for the trial. An additional outcome measure is identification of recommended phase 2 dose of CLR 131 in children and adolescents until a non-tolerated dose is defined, with a decision pertaining to dose escalation made upon review of data from a complete cohort.

The estimated enrollment for the trial is 30 patients and the estimated study completion date is December 2020.

“This designation, combined with our receipt of FDA Orphan Drug Designation for Ewing’s sarcoma last month, will help support our efforts to optimize the drug development path in this indication and, if successful, enable this new therapeutic candidate is made available to patients as rapidly as possible,” said Dr Friend.

Previously, CLR 131 was granted an orphan drug designation for the treatment of Ewing’s sarcoma, rhabdomyosarcoma, and neuroblastoma; it was also previously granted a rare pediatric disease designation for the treatment of neuroblastoma.