Technology to Assess Neurons Gives New Life to San Diego’s Afraxis

that it is really collaborative,” Stengone said in a telephone call. “We have formed a joint governance committee to oversee everything, and we’re working on downstream [drug discovery] milestones.”

The new Afraxis technology significantly advances neuroscientists’ ability to rapidly analyze dendritic spines—the pinhead-like protrusions along the neuron’s cell body, Stengone said. The technology also has comes at a time when researchers have begun to correlate the size and density of dendritic spines with strong synaptic activity—which in turn is strongly associated with learning, memory, and cognition.

The new Afraxis system, named the Enhanced Spine Platform, can analyze about 250,000 dendritic spines per month. That is both fast and accurate enough to be used in drug discovery, Stengone said. The technique wasn’t practical before now, he explained, because it would take an academic lab using conventional technology six to nine months to analyze 3,000 to 5,000 dendritic spines. That was a method that took too long and did not generate enough data to ensure accuracy.

“What we’ve been able to do is change the paradigm for dendritic spine analysis and characterization,” Stengone said. In developing drugs for CNS disorders, scientists must often rely on behavioral measures to assess whether or not a prospective drug is effective.

He said the potential value of technology that relies on more objective measurements became apparent after a group of German scientists published a 2009 study of two promising drugs (known as gamma-secretase inhibitors) for treating Alzheimer’s disease.

At the time, Eli Lilly was developing the gamma-secretase inhibitor semagacestat to reduce the buildup of harmful amyloid plaques in Alzheimer’s patients. But the German group’s study revealed a potential adverse side effect—the drugs also dramatically reduced the density of dendritic spines in the neurons of mice.

Lilly terminated its semagacestat program nearly a year later—after preliminary findings from two late-stage clinical trials involving more than 2,600 patients showed that the drug appeared to accelerate patients’ cognitive decline as well as their ability to perform daily activities.

“It was very compelling data,” Stengone said. Taken together, the German study and the adverse results of Lilly’s semagacestat program indicated that a drug could cause abnormalities in dendritic spine size and density—and that, in turn, could result in negative cognitive effects.

Since then, Stengone said additional studies have suggested that dendritic spine abnormalities underlie many CNS disorders, including autism, schizophrenia, and Alzheimer’s.

At Afraxis, Stengone and others concluded that the company’s technology could become a valuable litmus test for Big Pharmas as they select specific compounds from a portfolio of CNS drug candidates as the ones that would be most likely to succeed in clinical trials.

“We think we offer value that wasn’t there before in terms of de-risked value,” Stengone said. “We’ll be growing the bottom line quite significantly going forward.”

Author: Bruce V. Bigelow

In Memoriam: Our dear friend Bruce V. Bigelow passed away on June 29, 2018. He was the editor of Xconomy San Diego from 2008 to 2018. Read more about his life and work here. Bruce Bigelow joined Xconomy from the business desk of the San Diego Union-Tribune. He was a member of the team of reporters who were awarded the 2006 Pulitzer Prize in National Reporting for uncovering bribes paid to San Diego Republican Rep. Randy “Duke” Cunningham in exchange for special legislation earmarks. He also shared a 2006 award for enterprise reporting from the Society of Business Editors and Writers for “In Harm’s Way,” an article about the extraordinary casualty rate among employees working in Iraq for San Diego’s Titan Corp. He has written extensively about the 2002 corporate accounting scandal at software goliath Peregrine Systems. He also was a Gerald Loeb Award finalist and National Headline Award winner for “The Toymaker,” a 14-part chronicle of a San Diego start-up company. He takes special satisfaction, though, that the series was included in the library for nonfiction narrative journalism at the Nieman Foundation for Journalism at Harvard University. Bigelow graduated from U.C. Berkeley in 1977 with a degree in English Literature and from the Columbia University Graduate School of Journalism in 1979. Before joining the Union-Tribune in 1990, he worked for the Associated Press in Los Angeles and The Kansas City Times.