Cellectar Biosciences to Present Three Posters Highlighting Durable Clinical Activity of Iopofosine I 131 in Waldenström Macroglobulinemia at the American Society of Hematology Annual Meeting and Exposition

Updated CLOVER WaM Phase 2b analyses show durable responses in heavily pretreated patients and suggest greater benefit when used earlier in treatment paradigm

Company to present Phase 3 trial-in-progress design as site activation advances, first patient dosing remains on track for 1Q 2027 and FDA filing for accelerated approval remains targeted for 1H27

FLORHAM PARK, N.J., Nov. 04, 2026 (GLOBE NEWSWIRE) -- Cellectar Biosciences, Inc. (NASDAQ: CLRB), a late-stage clinical biopharmaceutical company focused on the discovery and development of cancer therapies, today announced that three posters highlighting compelling data and clinical progress for its lead radiopharmaceutical candidate, iopofosine I 131 in Waldenström macroglobulinemia (WM), will be presented at the upcoming American Society of Hematology (ASH) Annual Meeting and Exposition taking place December 12 – 15 in New Orleans, Louisiana.

The presentations will summarize updated 12-month follow-up data from the Phase 2b CLOVER WaM clinical trial, including new analyses exhibiting a significantly longer duration of response in patients who received iopofosine I 131 after only two prior lines of therapy compared with more heavily pretreated patients. These findings strengthen the clinical rationale for iopofosine I 131 in relapsed or refractory WM and support its potential evaluation in earlier treatment settings, where substantial unmet need remains. The company will also present, for the first time, the detailed design of its Phase 3 confirmatory study in WM patients previously treated with a Bruton tyrosine kinase inhibitor (BTKi). Site activation and other start-up activities are underway for the company’s global Phase 3 confirmatory study, with first patient dosing anticipated in the first quarter of 2027.

“The new data being presented at ASH further strengthen the clinical profile of iopofosine I 131, underscoring its potential to deliver durable responses and address a significant unmet need in relapsed or refractory Waldenström macroglobulinemia,” said Jarrod Longcor, chief operating officer of Cellectar Biosciences. “These updated CLOVER WaM results demonstrate durable responses in heavily pretreated patients, while new analyses suggest the potential for even greater durability of benefit when iopofosine I 131 is used in earlier lines of therapy. These findings reinforce our confidence in its clinical potential as we advance our registrational strategy. In parallel, we are targeting the first half of 2027 for an FDA submission seeking accelerated approval. These planned milestones define a clear path forward as we work to bring iopofosine I 131 to patients with limited treatment options.”

About Cellectar Biosciences, Inc. Cellectar Biosciences is a late-stage clinical biopharmaceutical company focused on the discovery and development of proprietary 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.

The company’s product pipeline includes iopofosine I 131, which is a PDC designed to provide targeted delivery of iodine-131 (radioisotope). Iopofosine I 131 has been tested in Phase 2b trials as a treatment for relapsed or refractory Waldenström Macroglobulinemia (WM), in relapsed or refractory multiple myeloma (MM) and central nervous system (CNS) lymphoma. The CLOVER-2 Phase 1b study is evaluating iopofosine I 131 in pediatric patients with high-grade gliomas, for which Cellectar is eligible to receive a Pediatric Review Voucher from the FDA upon approval. The FDA has granted iopofosine I 131 Breakthrough, six Orphan Drug, four Rare Pediatric Drug and two Fast Track Designations for various cancer indications, and the EMA has granted iopofosine I 131 PRIority MEdicines (PRIME) designation.

Cellectar is also 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, and is currently being evaluated in a Phase 1b study for TNBC, which will determine the recommended dose for the subsequent Phase 2 trial. CLR 125 has been well tolerated in vivo and has demonstrated strong preclinical data showing reduction or inhibition of solid tumor growth.

In addition to these assets, the Cellectar team is developing CLR 121225 (CLR 225), an actinium-225 based program targeting solid tumors in indications with significant unmet need, such as pancreatic cancer, as well as proprietary preclinical PDC chemotherapeutic programs and multiple partnered PDC assets.

For more information, please visit https://www.cellectar.com/or join the conversation by liking and following us on the company’s social media channels: X, LinkedIn, and Facebook.

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