Cellectar Biosciences Presents Efficacy Data for Iopofosine I 131 in Waldenström Macroglobulinemia

FLORHAM PARK, N.J., Oct. 15, 2026 /CourierPR/ -- Cellectar Biosciences, a late-stage clinical biopharmaceutical company, has presented compelling efficacy data from a subset analysis of its Phase 2b CLOVER WaM clinical trial at the International Workshop for Waldenström Macroglobulinemia (IWWM), which took place from October 14 to October 16, 2026, in Palm Springs, California.

The analysis focused on a subgroup of 24 patients who had received Bruton Tyrosine Kinase inhibitor (BTKi) treatment immediately prior to receiving iopofosine I 131. These patients achieved an overall response rate (ORR) of 87.5%, a major response rate (MRR) of 79.2%, and a clinical benefit rate (CBR) of 100%. The median duration of response (DOR) was 16.0 months, and the treatment-free survival (TFS) was 19.1 months. Importantly, treatment-emergent adverse events (TEAEs) occurred in less than 10% of patients, with the only Grade 3 or higher TEAE being cytopenias.

The company is advancing plans to dose the first patients in the confirmatory Phase 3 randomized clinical trial in a post-first line, post-BTKi population. The registration-directed trial is expected to evaluate progression-free survival (PFS) as the primary endpoint, consistent with regulatory guidance. Cellectar is also preparing to submit a New Drug Application for accelerated approval with the U.S. Food and Drug Administration (FDA) in the first half of 2027, supported by the strength and maturity of the CLOVER WaM dataset.

In addition to iopofosine I 131, Cellectar Biosciences is developing CLR 121125 (CLR 125), an iodine-125 Auger-emitting program targeted for solid tumors, such as triple negative breast (TNBC), lung, and colorectal cancer. The company is also working on CLR 121225 (CLR 225), an actinium-225 based program targeting solid tumors in indications with significant unmet need, such as pancreatic cancer.

Cellectar Biosciences, Inc. (NASDAQ: CLRB) is focused on the discovery and development of drugs for the treatment of cancer, independently and through research and development collaborations. The company's core objective is to leverage its proprietary Phospholipid Drug Conjugate™ (PDC) delivery platform to develop the next-generation of cancer cell-targeting treatments, delivering improved efficacy and better safety as a result of fewer off-target effects.