New Injectable Bulking Agent for Stress Urinary Incontinence

May 08, 2023 at 05:42 pm by kbarrettalley


By Jane Ehrhardt

 

“We’ve had a lot of enthusiasm from women about this product over the last three years,” says Brent Parnell, MD, a urogynecologist with OB-GYN South. For the 15 million American women experiencing stress urinary incontinence (SUI), this newest injectable bulking agent could relieve them of embarrassing leakage every time they cough, laugh, run, sneeze, or jump, and without surgery.

Called Bulkamid, the water-based filler is injected via a cystoscope through the urethra under the skin of the bladder neck to bulk-up the space between the skin and the muscle. “That provides a little bit of an obstruction at the bladder neck to protect women from leaking,” Parnell says.

Injectables have been used for decades, but the success of the fillers has not been stellar. Initially, these injectable fillers were based on bovine collagen. However, allergies to the compound were common. Its effectiveness also tended to fade fairly quickly. Women were leaking again as soon as six to 12 months later. “It was rarely used because of these early failures, and went off the market,” Parnell says.

The next fillers were made out of calcium products. The calcium created a pseudo-stone that surrounded the urethra. “They did last better, but they had a lot of unfortunate side effects,” Parnell says, listing irritated voiding, symptoms similar to bladder infections, and discomfort. “So it was used sparingly.”

Bulkamid, however, has been popularized in Europe for the last 10 years, where it was developed by Contura, and is currently marketed in 25 countries. Approved by the FDA in January 2020 for SUI, the smooth, polyacrylamide hydrogel filler is 97.5 percent water. “When placed in the body, it remains a gel-like product that’s very soft and not noticeable,” Parnell says. “It feels like toy slime. It’s clear with a really squishy, soft, sort of tacky feel, and it maintains that consistency in the body.”

However, multiple injections may be needed. Parnell has done repeat injections as early as one or two months after the initial one. “When you inject patients a second time, you still see where the previous gel was injected, but it’s still soft,” Parnell says. “We simply go under the previous injections and fill in that space a little more. The bladder neck compresses, and they’re back to their daily life.”

The maximum number of injections documented so far is three, with most women who needed more filler requiring only one additional injection. “I’m not aware of any maximum number of repeat injections,” Parnell says. Should the hydrogel not work at all, then nothing prevents the women from switching to a surgical option.

For women with SUI who want to have more babies, Bulkamid offers potential for relief now, since surgical intervention has not been possible. “That’s because the support procedure is on the vagina, so when the baby passes through the vagina, it can tear up what has been done or potentially cause injury to the surrounding organs,” Parnell says. But with Bulkamid injections, the worst that can happen from a vaginal birth is needing to be reinjected.

“It has been a really phenomenal product,” Parnell says, showing 90 percent of the women satisfied with outcome. “That’s the highest rate we’ve ever had with one of these fillers. The past ones were around 60 percent.” Seven years After receiving the Bulkamid treatment, 67 percent of women in a 2021 study still reported feeling cured or improved.

That retrospective study published in Neurourology and Urodynamics included 1,500 women who had undergone Bulkamid injections since 2005. Just over 32 percent completed the seven years of follow-up. Of those, 2.3 percent reported a worsening of their incontinence, while 11 percent reported no change. Twenty percent had received a subsequent other incontinence procedure.

“It’s been revolutionary, especially for really active women who don’t want to stop what they’re doing to recover from a surgery,” Parnell says. “Patients go home the same day with no restrictions to resume their normal activities that day or the next, including work and exercise.

“Bulkamid has offered that in-between option we’ve needed for so long between the less effective conservative management and the more effective surgical management. It’s been a real game-changer.”

Parnell has done 150 Bulkamid procedures. Only three have moved on to surgery. “Every time I do one, I’m more convinced that it’s a low risk/high reward procedure,” he says. “If patients are willing to accept that it may not be permanent, there’s really no downside to trying it.”

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