On September 11, 2025 Cellectar Biosciences, Inc. (Nasdaq: CLRB, "Cellectar"), a late-stage clinical biopharmaceutical company focused on the discovery and development of drugs for the treatment of cancer, and ITM Isotope Technologies Munich SE (ITM), a leading radiopharmaceutical biotech company, reported a supply agreement for Actinium-225 (Ac-225). The agreement will support the clinical development of Cellectar’s actinium-labeled phospholipid ether (PLE) radiopharmaceutical candidates, including its Phase 1-ready compound, CLR 121225, for the treatment of solid tumors.
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CLR 121225 (225Ac-CLR 121225), a novel actinium-labeled PLE, is under investigation for the treatment of solid tumors, including pancreatic cancer. Cellectar’s proprietary PLE delivery platform allows for the design and development of novel radiopharmaceuticals that can selectively target and eradicate cancer cells. ITM is leveraging its two decades of medical isotope manufacturing to scale supplies of Ac-225 to ensure rapid, reliable isotope delivery.
"Our lead alpha-emitting program, CLR 121225, has demonstrated excellent anti-tumor effects in preclinical studies, especially in pancreatic cancer," said James Caruso, chief executive officer of Cellectar. "Our agreement with ITM supports our strategic approach to ensure continuous, high-quality supply of Actinium-225 we need to advance our pipeline candidates and to fully explore the potential benefits of this targeted alpha therapy for cancer patients."
Ac-225 is an important isotope for the development of next-generation radiopharmaceuticals, serving as a powerful alpha-emitting isotope used in targeted cancer therapies. The scarcity of high-quality Ac-225 has slowed the advancement of research and development of Ac-225 based programs. To overcome this challenge and support the timely advancement of its pipeline, Cellectar has constructed a network of Ac-225 suppliers ensuring access to a sufficient supply.
"This agreement reflects our strategic commitment to advancing global access to radiopharmaceuticals," said Dr. Andrew Cavey, chief executive officer of ITM. "We value our partnership with Cellectar and our shared belief in the potential of innovative radiopharmaceutical therapies to significantly improve outcomes for patients with cancer. With more than two decades of leadership in the field, a fully vertically integrated model, and our joint venture, Actineer, ITM is uniquely positioned to meet the growing global demand for this critical isotope."
Under the terms of the agreement, ITM will supply Cellectar with the required quantities to facilitate the clinical development of its therapeutic medical grade radioisotope, Ac-225, produced by Actineer Inc., the joint venture between ITM and Canadian Nuclear Laboratories. Reliable, scalable production sites are crucial to meet the growing demand for Ac-225, given limited supply and manufacturing complexities surrounding the isotope.
(Press release, ITM Isotopen Technologien Munchen, SEP 11, 2025, View Source [SID1234661162])