Cellectar targets Q3 2026 EU filing for iopofosine I 131 in Waldenstrom's
The submission rests on the CLOVER-WaM Phase 2 study, whose primary completion date has slipped six times since 2020 and now lands on the eve of the planned filing.
Executive Summary
- Cellectar Biosciences intends to file for conditional marketing approval in Europe for its lead radiotherapeutic in Waldenstrom's macroglobulinemia, a rare blood cancer, based on final data from its pivotal-track Phase 2 study.
- The company has secured EMA scientific-advice feedback supportive of a conditional filing and holds Fast Track and PRIME designations, positioning this as a first regulatory submission for the drug in any market.
- The trial's own completion date has moved repeatedly over the study's life and now falls just before the filing window opens, leaving little room between when the data locks and when the filing is due.
- No other industry-sponsored trial targets this same mechanism in this disease, so there is no direct comparator readout to benchmark the filing against.
The filing plan
Cellectar disclosed the plan in a January 9, 2026 announcement ahead of the J.P. Morgan Healthcare Conference, saying the European Medicines Agency's Scientific Advice Working Party had given feedback supporting a conditional marketing authorization filing for iopofosine I 131 in Waldenstrom's macroglobulinemia. James Caruso, the company's president and CEO, said the company is "focused on receiving a conditional marketing approval in 2027 from the EMA impacting approximately thirty countries, which collectively possess a larger WM population than the U.S.". The filing would rest on final results and a WM subset analysis from the Phase 2 CLOVER-WaM study, which the company also plans to present in 2026. CellectarCellectar Biosciences to Highlight Strategic Initiatives for 2026 at Upcoming Biotech Showcase ...Jan 9, 2026
The trial behind the filing
CLOVER-WaM is registered as NCT02952508, a Phase 2 study of iopofosine I 131 across several B-cell malignancies with an expansion cohort in Waldenstrom's macroglobulinemia. The trial targets 120 patients, is Active, not recruiting, and has run since July 2017. No results have posted to ClinicalTrials.gov to date. NCT02952508Study of Iopofosine I-131 (CLR 131) in Select B-Cell Malignancies (CLOVER-1) With Expansion in WaldenstromNCT02952508
A six-year completion slip
The study's primary completion date has moved six times: from July 2020 to September 2022 in February 2021, to June 2023 in August 2022, to November 2024 in August 2023, to December 2024 in September 2024, to December 2025 in March 2025, and most recently to June 22, 2026 in March 2026. Enrollment target rose from 80 to 120 patients over the same period. That sequence puts the primary completion date inside the same quarter the company has guided for its EMA submission, leaving a narrow gap between when final data would lock and when the filing is due. NCT02952508Study of Iopofosine I-131 (CLR 131) in Select B-Cell Malignancies (CLOVER-1) With Expansion in WaldenstromNCT02952508
Regulatory pathway to date
Iopofosine I 131 holds Fast Track designation from the FDA for relapsed or refractory Waldenstrom's macroglobulinemia, granted in 2021, and PRIME designation from the EMA for the same indication in CLOVER-WaM, granted in 2023. The company has separately said it confirmed a traditional accelerated approval pathway with the FDA for the same drug in WM. No FDA approval has been recorded for iopofosine I 131. CellectarCellectar Biosciences to Highlight Strategic Initiatives for 2026 at Upcoming Biotech Showcase ...Jan 9, 2026
The competitive field
No other industry-sponsored trial targets tumor cell membrane lipid rafts, the mechanism iopofosine I 131 exploits, in Waldenstrom's macroglobulinemia. The nearest active competitor identified in the broader Waldenstrom's landscape is a Phase 1 study of an unrelated small molecule from Lomond Therapeutics, which does not share iopofosine's target or delivery mechanism. Named agents active in the wider B-cell malignancy space, including bispecific antibodies such as teclistamab and mosunetuzumab and antibody-drug conjugates such as belantamab mafodotin, work through different mechanisms in different lines of therapy and are not direct comparators to a radiotherapeutic targeting lipid rafts.
This analysis was produced using AI-assisted reporting systems, AppliedXL data, and official public records. These systems undergo editorial review, quality checks, and regular audits by human experts. Errors may still occur, as with any automated system. Always consult the linked primary sources. Read our AI Editorial Policy.