Phoenix Biotechnology, Inc., a San Antonio, Texas based biotechnology company, was incorporated in Texas in 2003 to develop promising agents with minimal or no side effects for targeted therapy of malignant tumor growth. Targeted therapy has recently become the focus in the medical community for the treatment of oncologic diseases. Pharmaceutical companies are seeking to develop drugs that target particular and discrete targets in tumor cells providing maximum efficacy yet without affecting healthy cells.
PBI-05204 is just such a drug. Following a tradition of investigating plant sources for medicinal drugs, Phoenix Biotechnology has developed a patented modified supercritical CO2 extract of Nerium oleander that has been found both in vitro and in vivo to bind to just such discrete cellular targets in solid tumors.
A recently completed USFDA Open Label Phase I Trial of PBI-05204 in Advanced Cancer Patients at M.D. Anderson Cancer Center has demonstrated that PBI-05204 does indeed bind to selected specific cellular tumor cell targets causing cellular downstream changes to certain signal transduction pathways, and not to healthy cells. The primary target, with downstream targets as well, is a particular subtype of the Na,K-ATPase enzyme known as alpha-3. Phoenix Biotechnology research has shown that PBI-05204 has a strong affinity for tumor cells that express a relative abundance of this particular subunit. As an example, colon cells undergo a change from malignant to a normal appearing phenotype, which we believe makes this type of malignancy a prime candidate for PBI-05204 therapy.
A summary of responses for the initial 20 patients was stable disease in 9/20 patients (45%) with various tumor types after first restaging (2 months). Out of these, minor response was seen in 3 patients-one each with colorectal (17% decrease), bladder (11% decrease), and fallopian tube cancer (10% decrease).
In the neurological disease and disorder field, including ischemic stroke, Alzheimer's, and Huntington's, research continues at Duke University on PBI-05204 and some of its further fractionated compounds absent cardiac glycosides. Initial promising results has led to further funding by Phoenix Biotechnology. These studies have provided evidence that the neuroprotective activity of PBI-05204 is mediated through oleandrin and/or other cardiac glycoside constituents, but that additional, non-cardiac glycoside components of PBI-05204 may also contribute to the observed neuroprotective activity. Finally, we show directly that both oleandrin and the protective activity of PBI-05204 are blood brain barrier penetrant in a novel model for in vivo neuroprotection. Together, these findings suggest clinical potential for PBI-05204 in the treatment of ischemic stroke and prevention of associated neuronal death.
The Company is focusing its research efforts to develop products that conform with the new paradigm for the socially responsible approach to the treatment of cancer as described by the National Cancer Institute.
The new paradigm seeks to develop therapeutic agents and treatment regimens that will enable physicians to eventually deal with cancer as a chronic condition rather than an acute condition and enable patients to live extended lives with a high or improved quality of life.