Actinium Pharmaceuticals: A Better Approach to Targeted Cancer Treatment

Actinium Pharmaceuticals: A Better Approach to Targeted Cancer Treatment

Actinium Pharmaceuticals is a privately held biotech company that is developing innovative targeted cancer treatments based on its proprietary radio-immunotherapy technology platform. The Company’s lead product candidates in clinical development include Actimab-A and Iomab-B for the treatment of blood-based cancers.

Actinium Pharmaceuticals

Actinium’s drug candidates have demonstrated proof of concept data in over 300 patients treated in several Phase 1 and 2 clinical trials and works with prestigious universities and organizations for the clinical and technological advancement of its targeted anti-cancer pipeline, including Memorial Sloan Kettering Cancer Center, Johns Hopkins Medicine, Fred Hutchinson Cancer Center, University of Pennsylvania Health Center and MD Anderson Cancer Center.

As a private company, Actinium has raised over $60 million (M) in funding through several rounds of financing to advance its radio-immunotherapy pipeline that delivers radiation in a targeted manner to cancer cells to minimize side effects and damage to normal cells that is often associated with chemotherapy drugs and radiation therapy for the disease.

The Company’s initial seed funding was provided by a Dutch company (Organon) that is now part of global big pharma Merck (MRK). Actinium plans to conduct a $20M private placement sometime after Labor Day and will then consider alternative strategies to obtain a public stock listing such as a reverse merger into a public-traded shell company in order to access a much greater pool of capital to advance its radio-immunotherapy pipeline through potential commercialization.

Actinium utilizes an approach that is emerging in the field of cancer treatment whereby a cancer-targeted monoclonal antibody is linked to a cytotoxic agent that results in targeted killing of cancer cells while sparing normal healthy cells in the body. Below is a summary of competitors in the space of targeted, linked cancer therapeutics.

1.) alpha particle radiation emitters: Actinium and Algeta (ALGZF)…Algeta’s lead product candidate is ALPHARADIN (radium-223 chloride) which is partnered with Bayer (BAYRY) and is currently pending expected regulatory approval filings in the US and EU during 2H12 for the treatment of advanced prostate cancer that has spread to the bone. ALPHARADIN is a bone-targeting anti-cancer agent since radium mimics the action of calcium in the body thereby resulting in rapid and targeted uptake in new bone for the treatment of advanced cancers that have spread to bone.

2.) beta particle radiation emitters: Spectrum Pharmaceutics (SPPI), Immunomedics (IMMU), Novelos Therapeutics (NVLT) and GlaxoSmithKline (GSK)…alpha particles are 100X more powerful and do not travel as far once in the body compared to beta particles thereby offering the potential for much greater cancer-killing power in addition to less side effects on health cells away from the cancer site. Currently, Actinium’s Iomab-B is based on iodine which is a beta emitter, but the Company plans to transition this over to alpha-based radiation as with Actimab-A.

3.) toxin-linked approaches: Immunogen (IMGN), Seattle Genetics (SGEN), Peregrine Pharma (PPHM) and Pfizer (PFE)…toxin-based approaches depend upon uptake (internalization) by cancer cells in order to exert their cytotoxic (cancer cell killing) effects so this is a limitation of the approach since many cancers will not uptake the toxin-linked antibody combination.

Below is a summary of Actinium’s two lead product candidates:

1.) Iomab-B (CD45 targeted monoclonal antibody that is currently based on radioactive iodine which emits 90% beta and 10% gamma radiation w/ plans to convert the compound over to actinium-based alpha radiation) (licensed from Fred Hutchinson Cancer Center) is currently pending evaluation in a planned pivotal clinical trial for the treatment of blood-based cancer acute myeloid leukemia (AML) in relapsed or refractory patients over the age of 50. Iomab-B has been evaluated in over 250 patients as part of Phase 1 and 2 clinical trials as a last-resort treatment, demonstrating the ability to prepare patients for bone marrow transplant (Hematopoietic Stem Cell Transplantation or HCST) in an effort to reconstitute the patient’s bone marrow with normally functioning cells.

2.) Actimab-A (CD33 targeted monoclonal antibody licensed from Abbott Biotherapeutics, formerly PDL, linked to actinium 225 which emits the much stronger alpha radiation) is a second-generation product candidate in development for newly-diagnosed AML (in patients over age 60) which is currently being evaluated in a Phase I / II clinical trial that has demonstrated improvements in clinical outcomes and manufacturing advantages compared to the first-generation product (Bismab-A). The Company expects to complete the Phase 1 portion of the trial in about nine months (i.e. by early 2013) and conclude the Phase 2 portion by the end of 2013.

The Company also plans to apply its APIT (Alpha Particle Immunotherapy) platform to additional product candidates beyond Iomab-B that will include monoclonal antibody expansion (e.g. Actimab-B as a next-generation product for bone marrow conditioning regimen prior to HCST) and other indications such as anti-angiogenesis therapies to counter the new blood vessel formation associated with cancer growth and spread (metastasis) and the development of bio-betters (i.e. improved versions of biological agents that are already approved).

Actinium’s promising pipeline of targeted radio-immunotherapy cancer treatments improves upon competing targeted approaches utilizing lower powered beta-emitting radiation or cytotoxic agents. In addition, the Company is targeting large potential markets with blockbuster potential (i.e. over $1 billion in annual sales) and is poised to begin pivotal clinical trials for lead product candidate Iomab-B while continuing to progress Actimab-A through a Phase I / II clinical trial that is slated for completion by the end of next year as a public listing for the company is expected to occur later this fall and will likely generate substantial interest from biotech investors as the targeted cancer immunotherapy space is currently a hot area of development within the industry.

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