Benzinga | Sep 22, 2021 08:33AM EDT

Cellectar Biosciences Announces Completion Of Part A Portion Of Safety And Tolerability Study Of Iopofosine I-131 In Combination With External Beam Radiation

Cellectar Biosciences, Inc. (NASDAQ:CLRB), a late-stage clinical biopharmaceutical company focused on the discovery and development of drugs for the treatment of cancer, today announced the completion of the part A portion of a safety and tolerability study of iopofosine I-131 (iopofosine) in combination with external beam radiation (EBRT) in relapsed or refractory head and neck cancer. This Investigator initiated study is being conducted by the University of Wisconsin as part of a prestigious Specialized Program of Research Excellence (SPORE) grant awarded by the National Cancer Institute.



The University of Wisconsin clinical trial under direction of principal investigator, Dr. Justine Yang Bruce is evaluating the potential for iopofosine in combination with EBRT to reduce the total dose (Grays) and number of fractions of external beam radiation while maintaining favorable tumor response rates.

The reduction in the amount or fractions (doses) of EBRT has the potential to diminish the (number and severity of) adverse events associated with EBRT. Patients with head and neck cancer typically receive approximately 60-70 Grays (Gy) of EBRT given as 2 -- 3 Gy daily doses over a 6 week timeframe. Patients can experience long-term tumor control following re-irradiation in this setting; however, this approach can cause severe injury to normal tissue structures, significant adverse events and diminished quality of life. Part B of the study will further assess the safety and potential benefits of iopofosine in combination with EBRT in a cohort of up to 24 patients.

"These preliminary study results support the potential promise of iopofosine. We are pleased that the early phase of the University of Wisconsin study has demonstrated good tumor uptake of iopofosine at the planned doses as well as safety of this unique treatment approach in Head & Neck cancer patients," said John Friend, CMO of Cellectar. "We remain cautiously optimistic that iopofosine in combination with external beam radiation may offer improved outcomes for patients in this highly challenging to treat disease."

Dr. Justine Yang Bruce stated "Iopofosine offers a novel investigational approach for patients with difficult to treat tumors such as head and neck cancer. The ability to potentially reduce the total external beam radiation doses is meaningful and we look forward to continue exploring iopofosine's potential as a combination treatment in this indication."

In addition to head and neck cancer, Cellectar is currently investigating iopofosine in a global, pivotal expansion cohort in relapsed or refractory Waldenstrom's macroglobenemia (WM) patients who have received at least two prior lines of therapy, including those who have failed or had a suboptimal response to Bruton tyrosine kinase inhibitors. The WM cohort will enroll up to 50 patients to evaluate the efficacy and safety of iopofosine for marketing approval. The company is also evaluating iopofosine in highly refractory multiple myeloma patients in its Phase 2 CLOVER-1 study and relapsed/refractory pediatric cancer patients with sarcomas or brain tumors in the Phase 1 CLOVER-2 study.