Cellectar says EMA confirms eligibility to file for CMA for iopofosine I 131

Cellectar Biosciences (CLRB) announced that after a scientific advice procedure, the Scientific Advice Working Party of the European Medicines Agency advised that filing for a Conditional Marketing Authorization for iopofosine I 131 as a treatment for post-Bruton Tyrosine Kinase inhibitor refractory patients with Waldenstrom macroglobulinemia could be acceptable for a CMA. If approved, iopofosine I 131 could be commercially available in the 30 countries represented by the EMA in 2027. Iopofosine I 131 is Cellectar’s potential first-in-class, novel cancer targeting agent utilizing the company’s proprietary phospholipid ether as a radioconjugate monotherapy, for the treatment of WM for post-Bruton Tyrosine Kinase inhibitor refractory patients. Iopofosine I 131 has been granted PRIME designation from the EMA for the treatment of patients with WM who received at least two prior lines of therapy. WM is a B-cell malignancy characterized by bone marrow infiltration with clonal lymphoplasmacytic cells that produce a monoclonal immunoglobulin M that remains incurable with available treatments. The Company’s decision to file for CMA in Europe follows SAWP’s advice on the patient population for which iopofosine I 131 is acceptable for a CMA, particularly a discussion on a post-BTKi patient population, consistent with the majority of the patients enrolled in the CLOVER WaM Phase 2 study. Cellectar’s briefing document to the SAWP included iopofosine I 131’s safety database, CLOVER WaM clinical study results, subset analyses, and manufacturing information. It is not within the remit of the SAWP to determine whether the data shows the sufficiency of safety and efficacy for a CMA; however, the SAWP advised that iopofosine I 131 met the eligibility requirements for a CMA submission for the proposed patient population. As in the U.S., there remains a significant unmet medical need for the treatment of WM in Europe, where the condition affects an estimated 35,000 to 45,000 patients. The CLOVER WaM study results demonstrated an overall response rate of 83.6% and a major response rate of 58.2%. These data were presented as a podium presentation during the 66th Annual American Society of Hematology Conference in December 2024 by Sikander Ailawadhi, M.D., Professor of Medicine, Mayo Clinic. The U.S. NDA will be submitted once the confirmatory trial is underway and will be supported by data from the Phase 2b CLOVER WaM clinical trial that demonstrated a statistically significant major response rate compared to a null hypothesis of 20% and meaningful duration of response. The data set now includes the FDA-requested 12-month follow-up results on all patients from the trial and new subset analysis of data from patients immediately following BTKi treatment failures regardless of line of therapy. The Company plans to share these new data at an upcoming medical or scientific conference. The U.S. FDA has granted iopofosine I 131 Breakthrough Therapy, Fast Track and Orphan Drug Designations for the treatment of r/r WM.