FDA Grants Rare Pediatric Disease Designation to 177Lu-omburtamab-DTPA for Medulloblastoma

177Lu-omburtamab-DTPA was granted a rare pediatric disease designation (RPDD) by the FDA for patients with medulloblastoma, according to a press release from developer Y-mAbs Therapeutics, Inc.

The monoclonal B7-H3 antibody that has been radiolabeled with lutetium-177 is currently under investigation as part of a multicenter phase 1/2 study (NCT04167618) in pediatric patients with recurrent or refractory medulloblastoma, as well as in a multicenter phase 1 study (NCT04315246) in adult patients with B7-H3–positive central nervous system tumors or leptomeningeal metastases. Investigators stated that both indications may work to address unmet needs within both patient populations.

“The RPDD makes us eligible for a Priority Review Voucher (“PRV”) upon potential approval of the biologics license application for this rare pediatric cancer. Among our leading compounds under development, four now have RPDDs, and this designation for 177Lu-omburtamab-DTPA further increase our chances of ultimately receiving multiple PRVs,” Thomas Gad, founder, chairman, and president of Y-mAbs Therapeutics, said in a press release.

The pediatric study, which has an estimated enrollment of 40 patients, utilized a 3+3 sequential group design in part 1, which was a dose-escalation phase. Patients were administered a dosimetry dose that was followed with the maximum of 2 5-week cycles of treatment with intracerebroventricular omburtamab. In part 2 of the study, patients included in the cohort expansion received a maximum of 5 5-week cycles and intracerebroventricular omburtamab based on the recommended dose from part 1. The end of treatment will occur within 5 weeks of the last cycle, wherein patients will enter the follow up period. Patients will be followed for up to 2 years following the last dose of treatment.

Moreover, the adult study has an estimated enrollment of 63 patients. In the dose-escalation portion of the study, a 3+3 sequential group design was utilized, wherein patients were treated with a dosimetry dose followed by a maximum of 5 5-week cycles of treatment. In the cohort-expansion portion, patients were given the recommended dose from part 1 until experiencing leptomeningeal metastatic progression, unacceptable toxicity, or up to a maximum of 5 cycles. Notably, the number of cycles were determined based on the final cycle, after which patients entered the follow up period. Patients were followed for up to 1 year following the first dose for part 1 and 2 years after the first dose for part 2.

Omburtamab has been exclusively license to Memorial Sloan Kettering Cancer Center, leading to a licensing arrangement in which the institution has institutional financial interests in the therapy.

Reference

Y-mAbs’ 177Lu-omburtamab-DTPA for the Treatment of Patients with Medulloblastoma Granted Rare Pediatric Disease Designation by FDA. News release. Y-mAbs Therapeutics. October 7, 2021. Accessed October 11, 2021. https://bit.ly/30fGIQ6