Actinium completes Actimab-A Phase I/II study on Acute Myeloid Leukemia

Actinium Pharmaceuticals, Inc. a biotechnology company focused on developing innovative, alpha particle radiotherapy targeted cancer treatments addressing major unmet medical needs, today announced that it has successfully treated the first cohort of patients in a Phase I/II study of Actimab-A™ in Acute Myeloid Leukemia (AML) clinical trial. Patients were treated at Memorial Sloan Kettering Cancer Center in New York City.

Patients enrolled in the first cohort in this ongoing trial were treated at a dose level of 0.5 microCi/kg of Actimab-A™, with two consecutive doses given a week apart. Actimab-A™ treatment consists of the isotope Actinium 225 attached to the anti-CD33 monoclonal antibody lintuzumab (HuM195). 

"As we continue to achieve our stated milestones, completion of the first cohort brought us another step closer to the Phase II portion of the trial," said Dr. Dragan Cicic, the CEO of Actinium Pharmaceuticals. "We are looking forward to accelerated accrual and timely completion of the current trial and moving into Phase II as planned."

This Phase I/II Actimab-A multi-center multi-dose study builds on the previous Phase I/II single center Bismab-A study (which used the less potent bismuth-213 isotope), and an earlier Actimab-A™ phase I single ascending dose study. The Bismab-A study demonstrated efficacy of API's alpha particle-linked to HuM195 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 are 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.