also activated a receptor that BDNF binds to, known as TrkB. Neurons in the brain slices were protected from injuries related to a stroke, according to the 2014 study. A third report from 2016 said the drug may induce antioxidants that limit inflammation.
Xconomy asked Nagahara of UCSD to review Phoenix’s published data (he was previously not familiar with the company). Nagahara says the company’s drug is interesting, but there’s not enough data to call it scientifically compelling. He says he would like to see an additional animal study to better understand how the compound gets into and is distributed by the brain.
“The fact that this one does increase BDNF, it’s interesting and may have additional derivative effects,” Nagahara says, noting the potential anti-oxidant effects Phoenix published in 2016. “But I’m not exactly sure if that in itself would be impactful, considering that there are other drugs or things that can stimulate BDNF levels.”
Antidepressant drugs, such as serotonin reuptake inhibitors, have been known to elevate BDNF levels, Nagahara says. He added that the drug would appear more interesting if the company could show it can produce BDNF in a specific region of the brain. The receptors that BDNF binds to are found in multiple regions, elevating the risk of possible side effects. Nagahara and colleagues are pursuing research into a different method of inducing BDNF—delivering BDNF genes through a viral vector into part of the brain that may lead to additional production—in Tuszynski’s UCSD lab.
Phoenix’s Newman says he is open to additional studies, which is part of the reason the company is looking for partners.
With the abysmal clinical record of Alzheimer’s drug, neurologists advocate testing as many methods as possible for treating Alzheimer’s, which affects some 5.5 million people in the U.S., according to the Alzheimer’s Association.
“As a field, we shouldn’t be shy about pushing anything that is based on solid biology and might make sense,” says George Bloom, a professor of biology, cell biology and neuroscience at the University of Virginia. Bloom is studying the underlying reasons that a healthy neuron converts to one with signs of Alzheimer’s or Parkinson’s disease.
Roots in Oleander
The Phoenix drug is an extract of the oleander plant, a flowering shrub that grows around the world and was brought to Texas in the 1840s, according to Texas A&M. Phoenix creates the extract by applying carbon dioxide to it under certain pressure and temperature conditions—a process called supercritical CO2 for which the company has a patent.
There’s one caution to oleander and other similar plant extracts, known as cardiac glycosides: Too much can be toxic. Digoxin, one of the better known drugs developed from an extract of another cardiac glycoside, foxglove, is used to treat heart failure. But it can also cause irregular heartbeat and other side effects. The same is true for oleander.
Phoenix says it developed a safe dosing regimen during the Phase 1 cancer trial, though the same safety standards don’t necessarily apply to neurodegenerative disorders. In cancer, Newman says he wants to test the drug in combination with chemotherapy, but that would cost money that the company doesn’t have, which is a reason Phoenix is looking for a deal.
Phoenix has been getting advice from Fred Frank, a longtime biotech investment banker who was once the vice chairman of Lehman Brothers and is now the chairman of New York- and San Francisco-based Evolution Life Science Partners, says Addington, a former chemical manufacturing and oil and gas executive.
Phoenix says it has received interest from a potential suitor.
Newman says he’s open to any type of deal, but “would like to (stay involved), since this is kind of my baby. I certainly don’t want to see somebody buy it and put it on the shelf.”
Newman is also chief science officer and a shareholder of a Phoenix spinout that sells oleander-based cosmetics and has raised eyebrows in a news publication with claims of clinical proof and “age-defying” ingredients; he says it operates independently of Phoenix.
