- Phase 2 clinical trial is currently active at 16 clinical trial sites in the United States, surpassing the 10 clinical trial sites that were planned for the trial

- Actinium affirms guidance for interim analysis by year-end 2017 and top line data in the first half of 2018

NEW YORK, Oct. 04, 2017 (GLOBE NEWSWIRE) -- Actinium Pharmaceuticals, Inc. (NYSE American:ATNM) ("Actinium" or "the Company"), a biopharmaceutical company developing innovative targeted therapies for cancers lacking effective treatment options, provided an update on its Actimab-A drug candidate in acute myeloid leukemia (“AML”). The Phase 2 trial is currently enrolling patients with AML age 60 and older who are unfit for standard induction chemotherapy. The Phase 2 clinical trial is now active at 16 clinical trials sites and Actinium has reiterated its previously announced guidance for the trial including a planned interim analysis by the end of 2017 and top line data in the first half of 2018. AML is one of the most common forms of leukemia. Approximately 21,000 patients are diagnosed with AML each year with the median ago of diagnosis being 68 years of age. Patients with AML over the age 60 who are ineligible for standard induction chemotherapy have limited treatment options and have a poor prognosis. Actinium’s Actimab-A targets CD33, a marker expressed in approximately 80-90 percent of patients with AML, via a monoclonal antibody that has been linked to actinium-225 (“Ac-225”), an alpha emitting radioisotope.

Dr. Mark Berger, Actinium’s Chief Medical Officer said, “We at Actinium have great confidence in our alpha-particle technology based drug candidate, Actimab-A, and in its ability to benefit patients. This Phase 2 trial in patients age 60 and older will evaluate the ability of Actimab-A to achieve remissions in these poor prognosis patients. The opening of additional sites will help us achieve our goal of an interim analysis by the end of 2017 and topline data in the first half of 2018. The results from the interim readout at year-end are expected to provide valuable insights into the best ways to use Actimab-A and how to differentiate it from other agents. We expect these insights to inform our development strategy going forward.”

Actinium’s Actimab-A phase 2 trial is currently open for recruitment at the following centers: 

Sandesh Seth, Actinium’s Chairman and Chief Executive Officer said, “CD33 is a validated target in AML and in our experience a resurgent area of interest amongst the medical community post the recent reapproval of Mylotarg. Importantly, the CD33 space that continues to garner much interest as evidenced by recent drug approvals, strategic transactions and a robust development pipeline represented by several major pharmaceutical and biotechnology companies. We believe that Actimab-A has the potential to be best in the CD33 class given the combination of its potency as a single agent, its relatively simple administration via two injections, and its relative benign safety profile. We look forward to updating by year-end on the significant progress we are making with the Actimab-A trial.”

About Actimab-A

Actimab-A, Actinium's most advanced alpha-particle therapy product candidate, is currently in a 53-patient, multicenter Phase 2 trial for patients newly diagnosed with AML age 60 and above that are ineligible for standard induction chemotherapy. Actimab-A is being developed as a first-line therapy and is a 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 for newly diagnosed AML in patients 60 and above by the U.S. Food and Drug Administration.

About Actinium Pharmaceuticals, Inc.

Actinium Pharmaceuticals, Inc. is a biopharmaceutical company developing innovative targeted therapies for patients with cancers lacking effective treatment options. Actinium's proprietary platform utilizes monoclonal antibodies to deliver radioisotopes directly to cells of interest in order to kill those cells safely and effectively. The Company's lead product candidate Iomab-B is designed to be used, upon approval, in preparing patients for a hematopoietic stem cell transplant, commonly referred to as bone marrow transplant (“BMT”). BMT is often the only potential cure for patients with blood-borne cancers but current standard preparation for a transplant requires chemotherapy and/or total body irradiation that result in significant toxicities. Iomab-B aims to enable a faster and less toxic preparation of patients seeking BMT, potentially leading to increased transplant success and survival rates. The Company is currently conducting a single pivotal 150-patient, multicenter Phase 3 clinical study of Iomab-B in patients with relapsed or refractory acute myeloid leukemia (“AML”) age 55 and older. The Company's second product candidate, Actimab-A, is currently in a multicenter open-label, 53-patient Phase 2 trial for patients newly diagnosed with AML age 60 and over. Actimab-A is being developed to induce remissions in elderly patients with AML who lack effective treatment options and often cannot tolerate the toxicities of standard frontline therapies. In addition, Actinium is developing Actimab-M, which is being studied in patients with relapsed or refractory multiple myeloma in a Phase 1 clinical trial. Actinium is also utilizing its alpha-particle technology platform to generate new drug candidates based on antibodies linked to the element Actinium-225 that are directed at various cancers that are blood-borne or form solid tumors. More information available at www.actiniumpharma.com and Twitter feed @ActiniumPharma, www.twitter.com/actiniumpharma.

Forward-Looking Statements for Actinium Pharmaceuticals, Inc. 
This news release contains "forward-looking statements" as defined in the Private Securities Litigation Reform Act of 1995. These statements are based on management's current expectations and involve risks and uncertainties, which may cause actual results to differ materially from those set forth in the statements. The forward-looking statements may include statements regarding product development, product potential, or financial performance. No forward-looking statement can be guaranteed and actual results may differ materially from those projected. Actinium Pharmaceuticals undertakes no obligation to publicly update any forward-looking statement, whether as a result of new information, future events, or otherwise.

Contact:

Actinium Pharmaceuticals, Inc.
Steve O'Loughlin
Vice President, Finance and Corporate Development
soloughlin@actiniumpharma.com

Investor Relations
Marek Ciszewski, J.D.
949.574.3860
ATNM@liolios.com

Released October 4, 2017