CHICAGO -- A 44-year-old architect endured impotence and gastrointestinal disorders as he tried for more than two years to find out which medicine could cure his depression. His own brain might provide the answer.
The Chicago resident, who has given up his search, is one of millions of people who might benefit from technology that allows scientists to peer inside patients' brains in hopes of cutting down the arduous process of evaluating antidepressants.
Scientists can use at least three methods -- positron emission topography (better known as PET), functional Magnetic Resonance Imaging (MRI), or electroencephalogram (EEG) -- to study the brain and its functions.
Aspect Medical Systems has developed a system based on the EEG, which records the firing of brain cells, blood flow and other activity, to gauge the effectiveness of antidepressants.
The Newton, Massachusetts, company's device, developed with the University of California at Los Angeles, is a disposable strip of electrodes that affixes to the forehead and feeds electronic signals into a monitor. It measures activity in the frontal lobe, where depression often manifests itself.
"You can see changes in the brain 48 hours after the patient takes the drug," said Andrew Leuchter, vice chairman at UCLA's Department of Psychiatry and Behavioral Sciences. Leuchter, who has an advisory role at Aspect, said the monitoring device could cut 80 percent off the time it normally takes to do human clinical trials.
"There are 25 common antidepressants on the market," added Phil Devlin, vice president of Aspect's neuroscience unit. "Without the technology, every person becomes their own clinical trial."
Last year global sales of antidepressants hit $19.5 billion, according to marketing research firm IMS Health. The lion's share came from seven drugs, including GlaxoSmithKline's Paxil, Pfizer's Zoloft and Wyeth's Effexor. Eli Lilly's Prozac and generic forms of it are also widely used.
It can take months, even years, for a doctor to prescribe the best-performing antidepressant because people react differently to different drugs. Most antidepressants take at least two weeks to alleviate symptoms, creating a sometimes agonizing delay in determining how well a particular drug works.
Aspect, which went public in 2000 and has been focusing on anesthesia, initially plans to sell its device to the pharmaceutical industry. The company says two unnamed drugmakers will soon begin using the technology to help evaluate their antidepressants. Later Aspect will aim for clinical use, in hopes that Americans who suffer from depression won't have to spend years, often unsuccessfully, to find an effective cure.
"Our goal is to make brain monitoring as common as heart monitoring," Devlin said.
The company, which has been losing money since mid-2000 but hopes to reach break-even in the second half of this year, would not disclose pricing or sales goals for its product.
Critics say brain imaging is still a crude and inexact science.
Moreover, each method of imaging has its disadvantages. One drawback of PET, for example, is that it uses radiation. And while functional MRI provides high spatial resolution, it is slow because it is based on blood flow. Aspect chose EEG-based technology because it can capture subtle changes in the brain over very short periods of time, Leuchter said.
But Dr. Helen Mayberg, a psychiatrist at Emory University in Atlanta, was skeptical about Aspect's device.
"Depression isn't like a stroke in that we know where it's coming from," Mayberg said. "There's no data to show that it's coming from the frontal lobe. There are changes in many other parts of the brain."
She uses PET images, which provide a more detailed picture of the brain, to study patients who are undergoing different types of therapy. Some parts of the brain responded to drug treatment, she has found, while others responded to talk therapy. But scientists still do not know enough about depression to determine whether a drug will work for a specific patient, she said.
"The bottom line is that one size doesn't fit all, and there's no magic bullet for the drug companies to ensure 100 percent market share," Mayberg said. "Not until we understand depression better."
Meanwhile, the Chicago architect, who did not want to be identified, said he would be willing to try Aspect's new device if his doctor thought it would help him find an effective drug.
"Sure, I'd give it a shot, as long as my insurance paid for it," he said. "But we all know how insurance companies are when it comes to (paying for) new technology."
