Epeius Biotechnologies announces Phase I/II study results of Rexin-G and Reximmune-C for cancer immunotherapy

Epeius Biotechnologies Corporation (www.epeiusbiotech.com) today announces the clinical results of the study entitled "A Phase I/II Study of Intravenous Rexin-G and Reximmune-C for Cancer Immunotherapy: The GeneVieve Protocol" at the ASCO Annual Meeting on June 6, 2010. The presentation will be made by Dr. Jorge G. Ignacio, Chairman of the Cancer Institute and Bioethics Committee-Philippine General Hospital, and Principal Investigator of the study.

SUMMARY: Rexin-G and Reximmune-C are tumor-targeted retrovectors bearing a cytocidal anti-cyclin G1 construct and a controllable GM-CSF expression construct, respectively. The working hypothesis underlying this two-tier complementary approach to tumor eradication and cancer vaccination is that a personalized vaccination of a patient against his or her own specific cancer can be achieved by combining (1) a targeted vector bearing a tumoricidal payload, i.e. Rexin-G, with (2) a targeted vector bearing a potent immuno-stimulatory (GM-CSF) gene, i.e. Reximmune-C. In this model, Rexin-G is first administered to control tumor growth and expose neoantigens within the tumor microenvironment, followed by defined pulses of Reximmune-C, intended to recruit the patient's immune cells into these lesions, thereby prompting immunologic activation, recognition of tumor neoantigens, and induction of a beneficial antitumor immunity. The initial results of a Phase I/II dose escalation study showed that, in addition to the expected tumoricidal effects of Rexin-G, histopathologic examination of biopsied tumors from patients with a diversity of cancer types revealed targeted nanoparticle delivery, GM-CSF transgene expression, and localized immune responses within the lesions. Importantly, no circulating GM-CSF protein was detected and no dose limiting toxicity was observed throughout the treatment period. Moreover, there appears to be a significant survival benefit which suggests that this two-tier approach has considerable merit as a therapeutic vaccine.