Pain management researchers in the School of Medicine are recruiting people who’ve had shingles to test the effectiveness of an investigational drug designed to reduce the severe pain that can last for months or years after a bout with the disorder.
Shingles is an inflammation of nerves that can affect any part of the body, commonly in the chest, face, arms or legs. Also known as herpes zoster, shingles is caused by the same virus that causes chicken pox.
Shingles strikes an estimated 800,000 people each year in the United States. About 20 percent to 30 percent of people older than 60 get shingles, and half of those who develop the painful rash continue to have pain, called post-herpetic neuralgia, after the rash disappears.
“The pain that lingers after the rash goes away is thought to occur as a result of alterations in the function of both the peripheral and central nervous systems,” said anesthesiologist Rahul Rastogi, M.D., who is principal investigator of the St. Louis study and sees patients at the University’s Pain Management Center. “Once those changes occur, people may experience pain even when there is no painful stimulus, or have pain that is evoked by exposure to a stimulus that normally would not cause a pain response.”
The investigators hope to counter those changes in pain sensation by treating post-herpetic neuralgia patients with the investigational medication.
Study volunteers will be eligible to receive the investigational drug REN-1654, which belongs to a class of chemical compounds known as benzamides — compounds that include antipsychotics and antidepressants.
REN-1654 is thought to have promise as a treatment for post-herpetic neuralgia because it has been shown to interfere with communication between nerve cell receptors that may carry pain messages.
To be eligible for the study, volunteers must be 55 or older and have a history of shingles, followed by persistent pain for 2-18 months after the onset of the rash.
People with cataracts, glaucoma and a history of herpes infection in the eye are not eligible.
Those who qualify will be randomly assigned to receive a daily dose of either the study medication or a placebo for 3-6 weeks.
Participants will receive free study-related physical exams, laboratory tests and investigational study medication.
They will be compensated for time and travel.
Participation in the study is expected to last for about 10 weeks and will involve five visits to the Pain Management Center in the Center for Advanced Medicine.
For more information, call study coordinator Patty Suntrup at 747-1709.