Novel temporary implant can offer a durable treatment for male urethral stricture by converting a complex open reconstructive surgery into a simple procedure.
Unmet Need
Urethral stricture disease causes fibrotic narrowing of the urethra leading to incomplete voiding, frequent and painful urination, and high rates of urinary tract infection. Graft-based reconstruction (substitution urethroplasty) is the curative gold standard for urethral stricture due to its high efficacy (85-90%). Unfortunately, few urologists can offer this durable therapy due to its technical complexity. Minimally invasive endoscopic interventions to incise or dilate the stricture are simple, and commonly performed by general urologists (GU). While minimally invasive, these procedures are also minimally effective with a high failure rate (50-90% stricture recurrence). In spite of this, endoscopic procedures are commonly repeated, leading to progression rather than resolution of the condition. Approximately 1% of the 21 million males on Medicare seek treatment for urethral strictures annually. Urologists estimate that 1 in 5 men will develop a stricture in their lifetime, with more than 600K stricture treatments performed annually in the US. This is expected to increase with the improved longevity of our aging population. Urologists and patients alike are dissatisfied with the limited solutions for treating urethral stricture disease.
Technology Overview
This invention is a novel medical device capable of performing endoscopic urethral reconstruction (EUR). An opportunity exists to combine the efficacy of open substitution urethroplasty with the simplicity of minimally invasive access through EUR. Building on prior innovative EUR attempts in the 1990s, this device allows for simple, efficient, and secured placement of a tissue or a skin graft at the urethral stricture site to promote patency. The device procedure involves the following steps: 1. Stricture incision to prepare an engraftment site. 2. graft harvest and fixation to the delivery device. 3. Endoscopic device delivery and deployment. 4. follow-up device retrieval after engraftment. Key innovations in this technology include mitigation of tissue ischemia and graft/device migration, atraumatic graft delivery, active graft release, and office-based atraumatic device removal.
The procedure begins with a graft harvest (buccal mucosa or other suitable tissue) and stricture incision with a custom graft-bed preparation tool. The harvested graft is loaded onto the device and atraumatically delivered to the target site. Once positioned, the temporary implant is deployed and the delivery tool is retrieved from the urethra. Urine can be voided either through the device or an indwelling catheter. After a 7-10 day recovery period, the patient returns for device removal (no anesthesia is required). The graft is released, and the implant is retrieved from the graft site. The result is improved urethral caliber with durable resolution of urethral stricture symptoms.
Stage of Development
The research team successfully demonstrated device immobility and graft adherence in a naive large-animal model. Currently, experiments are underway to validate the technology and demonstrate safety and increased urethral patency in a stricture-induced large-animal model. Extensive benchtop testing and validation have been performed to characterize mechanical performance and bond strengths. Simulated use-case tests involving residents and fellow physicians are being performed to assess usability and human factors. As the device approaches design freeze, the team intends to develop a small-batch manufacturing plan within the next 6-9 months.
The research team has successfully demonstrated device immobility and engraftment in a naive large-animal model. Extensive benchtop testing and validation have been done to characterize mechanical performance and device integrity. Further testing is underway to demonstrate safety and efficacy in a stricture-induced large-animal model. Simulated use-case tests by urologists are underway to assess usability and human factors. As the device approaches design freeze, a small-batch manufacturing plan will be developed over the next 6-9 months.
Target Market and Commercialization Pathway:
Urethral stricture disease can affect men of all ages, but the number and incidence increase with age. While the American Urology Association (AUA) guidelines state that no good data exists to determine prevalence (how many men have USD), studies indicate that nearly 1% of the 21 million males on Medicare seek treatment for urethral strictures annually. Some stakeholders estimate that 1 in 5 men will develop a urethral stricture in their lifetime. Approximately 52% of strictures are in the bulbar urethra - the most common site. A conservative estimate of 50% recurrence was applied for market projections, based on published failure rates following urethrotomy (58-92%). Thus the anticipated beachhead market of recurrent bulbar strictures in the United States totals ~153K.
No predicate device exists for our patent-pending technology, indicating a De Novo pathway. Following publications, we anticipate that the procedure would be added to the AUA urethral stricture guidelines, and move to a first-line treatment with mounting efficacy data. Cutting short the cycle of repeat management is both clinically effective and cost-effective; thus, swift integration in managed care systems is anticipated. As a temporary implant, the disposable product can be priced to enable profitable reimbursement through bundling. Eventually, a new CPT code for minimally invasive reconstruction would be needed. This approach is within the scope of other urological surgeries recently converted from open to minimally invasive. The current focus is the U.S. market, with follow-on markets in China and segments of the European market (based on expected reimbursement pathways).
Publication
- Elakkad, Chanya Godzich, et al. "Tools for transurethral deployment and fixation of graft for the management and treatment of urethral strictures." U.S. Patent No. 11,432,951. 6 Sep. 2022.
- Elakkad, Chanya Godzich, et al. "Transurethral deployment and fixation implant tool for the management and treatment of urethral strictures." Chinese Patent No. CN110139628B 26 May. 2023.
- Maruvada*, Teja, et al. "PD22-07 ANALYSIS OF PROGRESSIVE LUMENAL EXPANSION ON URETHRAL MICROPERFUSION USING LASER DOPPLER FLOWMETRY IN NEW ZEALAND WHITE MALE RABBITS." The Journal of Urology 201.Supplement 4 (2019): e390-e390.
- Maruvada, Teja, et al. "MP60-20 DEVELOPMENT OF A LARGE ANIMAL URETHRAL STRICTURE MODEL IN CANINES." The Journal of Urology 203.Supplement 4 (2020): e898-e898.
