NEWARK, NJ, USA I June 12, 2012 I Actinium Pharmaceuticals, Inc., a biotechnology company focused on developing innovative, alpha particle radiotherapy targeted cancer treatments addressing major unmet medical needs, today announced that the first patients have been treated in a Phase 1/2 study of Actimab-A™ in Acute Myeloid Leukemia (AML) clinical trial. Patients were treated at Memorial Sloan Kettering Cancer Center in New York.

Actimab-A™ treatment consists of the isotope Actinium 225 attached to the anti-CD33 monoclonal antibody lintuzumab (HuM195).

This Phase 1/2 multi-center study will build on the previous Phase 1/2 Bismab-A study with a less potent bismuth-213 (Bi-213) isotope and an earlier Actimab-A™ phase 1 study (where only one dose was administered). The Phase 2 portion of the Bismab-A study demonstrated efficacy of API’s alpha particle platform by producing a number of complete responses in difficult-to-treat relapsed, secondary and poor cytogenetics patients with no standard of care options available. The goal of the current study is to confirm efficacy and safety of Actimab-A, produced by an improved method of manufacture, and to study the effect of multiple doses of treatment. The population for this study will be patients with newly diagnosed AML who are over the age of 60 years, an age in which many chemotherapy regimens are not tolerated. In other published third party studies in AML, newly diagnosed patients had better responses than relapsed patients.

Dr. Joseph G. Jurcic of Memorial Sloan-Kettering Cancer Center is the Principal Investigator on the trial.

About Actinium 225

Actinium-225 decays by giving off high-energy alpha particles, which kill cancer cells. When actinium decays, it produces a series of daughter atoms, each of which gives off its own alpha particle, increasing the chances that the cancer cell will be destroyed. The technology was first demonstrated by Dr. David Scheinberg at Memorial Sloan-Kettering Cancer Center.

About Lintuzumab (HuM195)

Lintuzumab is a monoclonal antibody that targets CD33, found on myeloid leukemia cells. It is the humanized version of M195, the antibody initially developed by Dr. David Scheinberg of Memorial Sloan-Kettering Cancer Center.

Acute Myeloid Leukemia is the most difficult to treat form of leukemia. The majority of patients do not qualify for the commonly used chemotherapy regimen and their median survival following diagnosis is about 2 months without treatment.

About Actinium Pharmaceuticals

Actinium Pharmaceuticals, Inc. is a Newark, New Jersey based biopharmaceutical company that develops innovative alpha particle immunotherapeutics based on its proprietary platform for the therapeutic utilization of alpha particle emitting actinium-225 and bismuth-213 radiopharmaceuticals in association with monoclonal antibodies.

SOURCE: Actinium Pharmaceuticals