Actinium Pharmaceuticals, Inc. (ATNM)

Actinium Pharmaceuticals, Inc. is a clinical-stage biopharmaceutical company developing targeted radiotherapies, referred to as Antibody Radiation Conjugates (ARCs), designed to improve survival outcomes for patients with relapsed or refractory cancers who have exhausted existing treatment options, with a particular focus on relapsed or refractory acute myeloid leukemia (r/r AML) and its treatment pathway involving bone marrow transplant (BMT). The company's technology platform, protected by over 230 issued and pending patents worldwide, underpins its two lead product candidates: Iomab-B, an ARC combining the anti-CD45 antibody apamistamab with the radioisotope iodine-131, being developed as a targeted conditioning and disease-control agent to enable BMT access for AML patients previously considered unfit for transplant; and Actimab-A, an ARC combining the anti-CD33 antibody lintuzumab with the alpha-emitting radioisotope actinium-225, being developed as a therapeutic agent for AML patients, including in combination with chemotherapy and other targeted agents, through a collaboration with the National Cancer Institute. Iomab-B successfully met its primary endpoint in the Phase 3 SIERRA trial, showing statistically significant improvements in durable complete remission and overall survival, and the company is pursuing FDA approval (BLA) in the U.S. as well as, through commercial partner Immedica Pharma AB, marketing authorization in Europe, the Middle East and North Africa (EUMENA), with potential expansion into Canada, Latin America, and Asia-Pacific.

The company is also advancing Iomab-ACT, a next-generation conditioning regimen intended to improve outcomes for patients undergoing CAR-T and other cell and gene therapies, supported by an NIH-funded trial with Memorial Sloan Kettering Cancer Center and a new trial with UT Southwestern. Beyond its lead programs, Actinium maintains a pipeline of preclinical solid tumor programs targeting validated and novel cancer antigens, supported by research collaborations with companies such as Astellas Pharma, AVEO Oncology/LG Chem, and EpicentRx. The company's target markets include large quaternary care hospitals and top transplant and cancer centers, which concentrate the majority of BMT procedures and r/r AML patient care; its addressable markets span the U.S. and EU5 r/r AML population (estimated at over 85,000 patients), a broader blood cancer BMT-eligible population exceeding 165,000 patients annually in the U.S., and the rapidly growing CAR-T and gene therapy conditioning market, projected to reach approximately 93,000 patients in the U.S. by 2030.

Actinium's strategy centers on building a specialty, hospital-focused radiotherapeutics company, leveraging concentrated points of care at major transplant and cancer centers to commercialize Iomab-B and Actimab-A with a relatively small, efficient commercial and supply chain organization, while continuing to expand its ARC pipeline into other blood cancers and solid tumors.