Benzinga | Nov 16, 2021 08:31AM EST

Cellectar Biosciences Says Co's Iopofosine I-131 Exhibits Signals Of Efficacy In Phase 1 Study For Pediatric Brain And Solid Tumors

Cellectar Biosciences, Inc. (NASDAQ:CLRB), a late-stage clinical biopharmaceutical company focused on the discovery, development and commercialization of targeted drugs for the treatment of cancer, today announced that patients in a Phase 1 study of iopofosine I-131 ("iopofosine") in children and adolescents with relapsed and refractory high grade gliomas (HGGs) and soft tissue sarcomas, exhibited positive changes in various tumor parameters. The Phase 1 study is an international, open-label, dose escalation, safety study of iopofosine in children and adolescents with relapsed or refractory cancers, specifically HGGs, high risk neuroblastoma and select soft tissue sarcomas.



The independent data monitoring committee (DMC) had previously determined that doses up to 60 mCi/m2 were safe and tolerable and to initiate the 75 mCi/m2 dosing cohort. The DMC advised, based upon the initial data, to enrich the 60 mCi/m2 dose level for patients over the age of 10 with HGG and Ewing sarcoma. The initial response and tumor uptake were confirmed by further therapeutic responses, evidenced by changes in tumor parameters. This includes patients with relapsed HGGs experiencing over 5 months of progression free survival (PFS).

"Initial responses to iopofosine I-131 in relapsed pediatric brain tumors are most encouraging. Current treatment paradigms typically result in only 2-3 months1 of PFS and while there is no comparator in this study, iopofosine data to date have demonstrated nearly double the PFS versus historical data," said Laurence Reilly interim chief medical officer of Cellectar. "Based upon these data we will continue to enroll patients with high grade gliomas and soft tissue sarcomas, and we look forward to engaging with the FDA in order to outline a potential registrational pathway."

Pediatric HGGs are a collection of aggressive brain and central nervous system tumor subtypes including diffuse intrinsic pontine gliomas, glioblastomas, astrocytomas and ependymomas. Children with these tumors have a poor prognosis and 5-year survival of less than 30%.