Cellectar Biosciences Advances Iopofosine I 131 and Radioconjugate Pipeline at Biotech Showcase
Key Insights
Cellectar Biosciences plans to highlight its 2025 strategic initiatives at the Biotech Showcase during the JP Morgan Healthcare Conference.
The CLOVER-WaM study showed Iopofosine I 131 (search) achieved an 83.6% overall response rate in relapsed/refractory Waldenstrom's Macroglobulinemia (search).
Cellectar is advancing radiotherapeutic assets, including CLR 121225 and CLR 121125, into Phase 1/2a solid tumor studies.
Cellectar Biosciences, Inc. (NASDAQ: CLRB) is set to highlight its 2025 strategic initiatives at the Biotech Showcase, held during the 43rd Annual JP Morgan Healthcare Conference in San Francisco from January 13-15, 2025. James Caruso, president and CEO of Cellectar, will provide a corporate update, focusing on the advancement of Iopofosine I 131 (search) and the company's broader radioconjugate pipeline.
Iopofosine I 131: Targeting Waldenstrom's Macroglobulinemia
Iopofosine I 131 (search), a potential first-in-class cancer-targeting agent, is a radioconjugate monotherapy utilizing a phospholipid ether. Data from the Phase 2 CLOVER-WaM study (NCT02952508) demonstrated an impressive 83.6% overall response rate (ORR) and a 58.2% major response rate (MRR) (95% CI, 0.42 to 0.67) in patients with relapsed/refractory Waldenstrom's Macroglobulinemia (search) (WM). These results, presented at the American Society of Hematology Conference in December 2024, exceeded the study's primary endpoint of a 20% MRR.
"We remain committed to bringing iopofosine to WM patients, who have limited treatment options for this incurable disease," stated James Caruso. He added that ongoing communications with the FDA suggest a path forward for conditional U.S. market approval via the accelerated approval process, aligning with feedback from the European Medicines Agency (EMA) for conditional EU market authorization. The company is harmonizing recommendations from both agencies for a global approval strategy.
Cellectar anticipates that the confirmatory study will be a comparator, randomized controlled trial with 40-60 patients per arm, with full patient enrollment projected within 18 months of the first patient admitted. The company expects alignment with the FDA in the first half of 2025 and is assessing various approaches to bring iopofosine to patients, with a current cash runway extending into the fourth quarter of 2025.
Advancing Radiotherapeutic Pipeline
Beyond Iopofosine I 131 (search), Cellectar is focused on developing its radioconjugate Phospholipid Drug Conjugate™ (PDC) programs. CLR 121225, the company’s lead alpha-emitting actinium-225 radioconjugate, has shown activity and tolerability in preclinical models of pancreatic, colorectal, and breast cancer (search), demonstrating excellent biodistribution and tumor uptake. In pancreatic adenocarcinoma models, the lowest dose tested provided tumor stasis, while the highest dose resulted in tumor volume reduction. An Investigational New Drug (IND) application is planned for the first quarter of 2025.
CLR 121125, Cellectar’s lead Auger-emitting (iodine-125) PRC, has also demonstrated tolerability and activity in multiple animal models, including triple-negative breast cancer (search). The company's PDC platform facilitates targeted intracellular delivery, crucial for Auger emitters due to their short emission range. CLR121125 has received IND clearance, and a Phase 1b/2a dose-finding study in triple-negative breast cancer is planned. The company is currently evaluating the timing of study initiation for both CLR 121225 and CLR 121125.
Strategic Outlook
Cellectar's strategic initiatives for 2025 underscore its commitment to advancing targeted cancer therapies. The company's focus on radioconjugates and its PDC platform aims to deliver improved efficacy and safety for patients with limited treatment options. Cellectar's presentation at the Biotech Showcase will provide further insights into these strategic priorities and ongoing clinical programs.