Roanoke Times
Copyright (c) 1995, Landmark Communications, Inc.
DATE: SATURDAY, July 30, 1994 TAG: 9408010041
SECTION: VIRGINIA PAGE: C-1 EDITION: METRO
SOURCE: By MELISSA CURTIS STAFF WRITER
DATELINE: LENGTH: Medium
``Infants and people with advanced diseases, like AIDS and kidney failure, don't respond to vaccines like healthy people do. And as you get older, your response to vaccines keeps dropping off,'' said Dr. Thomas Evans, chief of the infectious disease section at the Veterans Affairs Medical Center in Salem.
But Evans thinks he might be able to change that.
For three years Evans has been researching DHEAS, a hormone found in the body. He has found that older animals given DHEAS respond better to vaccines.
``When given the hormone, the immune system becomes more like the immune system of a younger animal,'' he said. ``In a number of studies, the hormone markedly boosted [the animals'] response to the vaccine.''
Now Evans is testing how humans respond to vaccines when given DHEAS.
Evans gives patients four doses of the hormone before and after receiving a tetanus shot, a vaccination he said all individuals should have every 10 years.
Half of the patients will receive the hormone and half will receive a placebo, a sugar pill that has no effect. Evans said he then can compare the patients' responses to the vaccine with and without the hormone to see who responded best to the vaccine.
Patients are checked daily, and a month later Evans runs three blood tests to examine the results. Evans said he will not know which patients received the hormone and which did not until after the study is over.
``If you don't do it that way, you might be influenced or biased to think the hormone works when it might not,'' he said.
He already has tested 45 patients. Evans said he is aiming to test 35 more.
Volunteers must be 65 years or older, cannot have had a tetanus vaccine in the past 10 years and cannot have prostate cancer. Participants are paid $40. Individuals interested should call 982-2463, extension 1461.
And if the hormone does make vaccines work better?
Evans said he will look at other vaccines, including vaccinations for hepatitis, influenza and pneumonia, to see if the hormone improves patients' responses to those as well. He also will run studies in order to determine the optimal dose of DHEAS patients should take.
If the hormone improves the effectiveness of vaccines, Evans predicts a potential use of DHEAS by the HIV population and infants, other groups that have lowered responses to vaccinations.
Evans said a lot more research on DHEAS needs to be done before the hormone can be submitted to the Food and Drug Administration for approval to be marketed. Only Paradigm, the company that has the patent use rights to DHEAS, can do that.
But Evans' study is a step in that direction.
``This is one of the major studies to decide if [the hormone] is going to work,'' he said. ``If we can make vaccines work better, it will help prevent disease.''
by CNB