New Research Study Points to Potential of Oleandrin as Therapeutic Strategy for Treatment of HTLV-1, Which Affects Between 10 Million to 15 Million Worldwide

Dr. Robert A. Newman, President/Chief Science Officer Phoenix Biotechnology, Inc. (Photo: Business Wire)

Dr. Robert A. Newman, President/Chief Science Officer Phoenix Biotechnology, Inc. (Photo: Business Wire)

SAN ANTONIO--()--A new research study recently published as an “In Press” article in the Journal of Antivirals & Antiretrovirals ( [Volume 11, Issue 3, 2019] concludes that “phytomedical compounds, such as the cardenolide oleandrin, may one day represent a cost-effective therapeutic strategy to help combat enveloped virus infections (such as HTLV-1) in developing countries with limited access to modern antivirals.”

The study is the latest in a string of published research papers which speak to various potential uses of oleandrin, an extract from the common Nerium oleander plant, in disease treatments. Oleandrin is the key bioactive component of PBI-05204, a drug developed by Phoenix Biotechnology, Inc. (, of San Antonio, TX.

According to Robert A. Newman, PhD, President and Chief Science Officer of Phoenix Biotech, PBI-05204 is the only botanical drug that contains oleandrin which has gone through both Phase I and Phase II clinical trials and is currently under development.

The article is entitled “The Botanical Glycoside Oleandrin Inhibits Human T-cell Leukemia Virus Type-1 (HTLV-1) Infectivity and Env-Dependent Virological Synapse Formation.” Authors include Tetiana Hutchison, Lacin Yapindi, Aditi Malu and Robert Harrod (all with the Laboratory of Molecular Virology, Department of Biological Sciences in the Dedman College Center for Drug Discovery, Design & Delivery at Southern Methodist University), Robert A. Newman (previously with the Department of Experimental Therapeutics, University of Texas M.D. Anderson Cancer Center) and K. Jagannadha Sastry (Departments of Immunology and Veterinary Sciences, University of Texas M.D. Anderson Cancer Center). It is an open access article, freely available online.

HTLV-1 is a retroviral infection that affects T cells (a type of white blood cell). There is no cure or treatment for HTLV-1 and it is considered a lifelong condition. Some 10 million to 15 million people worldwide are infected with HTLV-1. Areas of the world that are endemic to the HTLV-1 virus are the Caribbean, southern Japan, equatorial Africa, Middle East, South America and Melanesia. Women are twice as likely to be infected as men.

Initial symptoms are subtle and include gait problems, unexplained falls, low back pain, constipation, urinary urgency/incontinence and numbness of pain in the lower limbs. While some patients are still ambulatory after one or two decades of disease, others may be confined to a wheelchair months after onset of the disease. Some persons infected with HTLV-1 develop a progressive neurologic disease named HTLV-1 associated with myelopathy/tropical spastic paraparesis. Approximately 2-5 percent of HTLV-1 carriers will develop ATL (acute T-cell lymphoma) and some will suffer from joint disease, inflammation of the eye, pneumonitis and thyroid problems.

The authors note that “…oleander extracts, including oleandrin…have been shown to have anti-proliferative, anti-inflammatory and anti-tumorgenic effects.” Further, they note, “a N. oleander-derived drug, PBI-05204, has completed both Phase I and initial Phase II clinical trials to test its efficacy and safety in patients with advanced solid cancers…PBI-05204 inhibited pancreatic tumor growth…and oleandrin inhibited tumor growth in a murine xenograft model of malignant glioma.”

“Moreover,” the researchers wrote, “oleandrin exhibited neuroprotective and protected neuronal tissues from damage, due to glucose and oxygen deprivation, dependent on the induction of brain-derived neurotrophic factor (BDNF), in brain slices and in vivo models of ischemic stroke.”

“It is an intriguing notion,” they stated, “that the ability of oleandrin to cross the blood-brain-barrier and inhibit HTLV-1 infectivity and the expression of viral antigens could have potential therapeutic implications for the treatment of HTLV-1 associated neuro-inflammatory disease…”

A number of previous studies have shown oleandrin’s ability to cross the blood-brain-barrier when the drug is administered orally. Collaborative work with Duke University found that PBI-05204 was effective orally against stoke mediated ischemic injury. The research found an increase in production of the critically important brain growth factor known as brain derived neuronal factor (BDNF) required for maintenance of healthy neurons as well as recovery from a decrease in oxygen and glucose commonly associated with stroke. In addition, the facile increase in BDNF due to administration of PBI-05204 also produced an important increase in antioxidant activity within brain tissue.

About Phoenix Biotechnology

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 and other life threatening diseases. 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 selectively discrete components of malignant cells providing maximum efficacy yet without affecting healthy cells.

PBI-05204 is just such a drug. Phoenix Biotechnology, Inc. 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 a discrete cellular target in solid tumors.

While the prevention and treatment of human malignant disease remains PBI's primary focus, novel, patented extracts of Nerium oleander continue to reveal promising avenues of research showing activity against certain viral and neurodegenerative diseases.


Sarah Duncan (210-828-4373 or


Release Summary

New Research Study Points to Phoenix Biotech's Oleandrin for Potential to Treat HTLV-1 virus which affects 10 million-15 million worldwide


Sarah Duncan (210-828-4373 or