Actimab-A: Phase 2

Candidate & Indication Development Stage
R & D Preclinical Phase 1 Phase 2 Phase 3
Actimab-A (f.d.) CD33 AML
Newly diagnosed patients
with AML over age 60
R & D Phase complete
Preclinical Phase complete
Phase 1 Phase complete
Phase 2 Phase in progress
Phase 3 Phase not started

Actimab-A targets CD33, expressed on a majority of AML cells via the antibody lintuzumab and delivers powerful actinium-225, which kills the AML cells. Actinium-225 is one of the most potent cytotoxic isotopes known to man but its energy only travels four (4) cell diameters sparing many healthy cells.

Actimab-A, Actinium's most advanced alpha particle immunotherapy (APIT) product candidate, is currently in a 53-patient, multicenter Phase 2 trial for patients newly diagnosed with AML age 60 and above. Actimab-A is being developed as a first-line monotherapy that is administered via two 15-minute injections that are given 7 days apart. Actimab-A targets CD33, a protein abundantly expressed on the surface of AML cells via the monoclonal antibody, HuM195, which carries the potent cytotoxic radioisotope actinium-225 to the AML cancer cells. Actinium-225 gives off high-energy alpha particles as it decays, which kill cancer cells and as actinium-225 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.

Actimab-A is a second-generation therapy from the Company's HuM195-Alpha program, which was developed at Memorial Sloan Kettering Cancer Center and has now been studied in almost 90 patients in four clinical trials. Actimab-A has been granted Orphan Drug Designation from both the U.S. Food and Drug Administration and the European Medicines Agency for newly diagnosed AML in patients age 60 and above.