Actinium Pharmaceuticals (NYSE:ATNM) is a clinical-stage biopharmaceutical company specializing in the development of targeted radiation therapies for oncology. The company’s proprietary platform harnesses alpha- and beta-emitting radioisotopes conjugated to monoclonal antibodies, with the goal of selectively delivering radiation to cancer cells while sparing healthy tissue. Actinium’s most advanced candidates are designed to address acute myeloid leukemia (AML) and other hematologic malignancies that require conditioning prior to allogeneic stem cell transplantation or direct anti-leukemic activity.
The company’s lead asset, Iomab-B, combines the anti-CD45 antibody with the beta-emitter iodine-131 and is engineered to ablate bone marrow in patients with relapsed or refractory AML who are eligible for transplant. In parallel, Actinium is advancing Actimab-A, which pairs an anti-CD33 antibody with Actinium-225, an alpha-emitting isotope, and Actimab-M, which also utilizes Actinium-225 but targets CD33 in elderly or transplant-ineligible AML patients. These candidates aim to deliver potent cytotoxicity at the single-cell level and have shown promising signals of efficacy in early-stage clinical trials.
Originally founded in 1997 under the name Sulfotransfer Technologies, Inc., the company rebranded as Actinium Pharmaceuticals in 2010 to underscore its focus on actinium-based radiopharmaceuticals. Over its history, Actinium has forged strategic collaborations with academic medical centers, contract manufacturing organizations and patient advocacy groups to support clinical development, manufacturing scale-up and patient access. The company is headquartered in New York City and conducts multi-center trials across the United States.
Under the leadership of President and Chief Executive Officer Hervé Hoppenot, Actinium has built a team of experienced drug developers, medical oncologists and nuclear medicine specialists. The company’s management also includes veterans in regulatory affairs, clinical operations and chemistry, manufacturing and controls (CMC), reflecting its dual expertise in biologics and radiochemistry. Actinium remains focused on advancing its pipeline through pivotal studies and regulatory interactions while exploring potential collaborations to expand its oncology portfolio.
