VUMC participates in depression study
The first large-scale, multi-center study of whether anti-depressants become less effective over time in moderately depressed individuals is being conducted at Vanderbilt University Medical Center and 19 other institutions across the country.
About 15 to 20 percent of people taking anti-depressant drugs have a good initial response, but will subsequently lose that good response after the third month, said Dr. Richard C. Shelton, associate professor of Psychiatry at Vanderbilt University Medical Center. Shelton is the principal investigator of the VUMC portion of the study, which is expected to enroll about 20 participants out of the total 400 participants.
The study will compare two different types of anti-depressants – fluoxetine (Prozac), one of a group of selective serotonin reuptake inhibitors (SSRIs) and venlafaxine (Effexor).
“This is more than just a simple horse race study, trying to see if one drug beats the other. It’s a differential effectiveness study to find out, first of all, if patients on each of these drugs are getting well at an equivalent rate, and then to see with those with an initial therapeutic response, how many relapse over time,” Shelton said.
Patients with moderate depression, who are found to need treatment, will be eligible for the study, Shelton said. The participants will be treated with either fluoxetine or venlafaxine. Those with a good initial response will continue with the study for 18 months. Those who don’t will receive other treatment.
Shelton said the outcome of the study may allow physicians to better tailor the treatment for depression to the patient. Investigators believe they will gain information during the study as to which drug works best for certain groups of people.
“My guess is that we’re going to find certain clinical predictors of response that will lead us into a deeper understanding of the kinds of people who will be appropriate for one kind of treatment or another,” Shelton said. “What that will then theoretically do, from a practical standpoint, is give us information about how to choose the appropriate treatment for the appropriate person. Those with sleep problems or those who are extremely anxious, for example, may do better with one drug or the other.”
About 17 million Americans are estimated to develop depression each year. But the incidence may be higher because people fail to seek help for depression and physicians are often reluctant to diagnose depression. Women have a significantly higher rate of depression than men. Depression is estimated to contribute to 50 percent of all suicides.
Wyeth Ayers, the pharmaceutical company that makes venlafaxine, is sponsoring the study with an independent grant. But the company has no control over the outcome.
“Wyeth is taking a courageous stance, which is: they believe their medication will stand up well but they’re not going to control the outcome. It could go either way,” Shelton said.
For more information, or to be evaluated for the study, call 343-9669.