UBC researchers seek trial participants for new pain-relieving medication
A mention of scrotal pain may give some grownups the giggles, but for the men who experience it, it's no laughing matter.
Dr. Ryan Flannigan, assistant professor and director of the male infertility and sexual medicine research program in the UBC department of urologic sciences and a senior scientist at the Vancouver Prostate Centre, treats men with this chronic condition.
"I've probably seen 75 to 100 men with chronic scrotal pain in the last six months," he says, adding that many cases go undiagnosed.
Dr. Ryan Flannigan
Treatment options for chronic scrotal pain include anti-inflammatory drugs, antidepressants, neuromodulators such as Gabapentin and, when there is no reversible cause such as hernia or infection, even surgery. When physiotherapy and medications fail, patients can also be treated with steroids or anesthetics, such as lidocaine, which is injected directly into the nerve-containing spermatic cord.
"Sometimes that can provide relief, but only for a short time," Flannigan says. "Lidocaine's effects last about one-and-a-half to two hours."
In an effort to find a treatment that will provide longer-lasting pain relief, Flannigan and other researchers from UBC, including Dr. Martin Gleave, head of the department of urologic sciences and executive director of the Vancouver Prostate Centre, researchers John Jackson and Veronika Schmitt from the faculty of pharmaceutical sciences, are launching a trial in July 2019. They're going to test the use of a polymer paste that will deliver medication more slowly. This paste is being developed by Sustained Therapeutics, a UBC spinoff company.
Chronic scrotal pain is defined as intermittent or constant, unilateral or bilateral pain experienced in the scrotal area that lasts for three months or longer and significantly interferes with daily activities. Teenagers to men in their 60s experience chronic scrotal pain, but it most commonly affects those in their twenties and thirties, peaking in the mid- to late-thirties.
Common causes include a previous infection, inflammation in the tube at the back of the testicles that stores and carries sperm, nerves that have been irritated or pinched during hernia repair, a blow to the testicle area and vasectomy. The cause is unknown in at least 44 per cent of cases.
Men with the condition often rate their pain level as three to five out of 10-with 10 being the worst-with flares to nine or 10.
"In many cases, it's very debilitating," Flannigan says. "People have to avoid certain activities such as walking, running and cycling. Even sitting or wearing form-fitting clothing can trigger pain, as well as intercourse and ejaculation. Some people are missing work and occasionally people are on disability because of it."
Upwards of 4.5 per cent of men report experiencing chronic scrotal pain but only half a per cent of them seek medical treatment.
"There's a lot of really good evidence that men are much less likely to seek medical care than women because of masculinity, identity and roles in our society, especially in younger adults," Flannigan says. "Those without a partner are at higher risk. Usually men's partners hold them accountable and encourage them to be assessed by a health care provider."
The first phase of the study will examine the safety and tolerability of an injectable lidocaine paste in men with spermatic cord block and define a recommended dose for further studies.
"These patients don't have many good options so it's exciting to think that this might improve their quality of life and relieve some of their chronic pain," says Flannigan.
With dozens of patients from the Yukon, Northwest Territories, Alberta and the Interior as well as the Lower Mainland seeking relief from protracted pain, Flannigan expects high interest in the clinical trial. Men keen to get involved can learn more by contacting the clinical trials unit at the Vancouver Prostate Centre
