Clinical evaluation of a compliant, degradable ureteral stent to reduce patient pain and improve tolerability

PROJECT SUMMARY Kidney stones represent a significant health concern both domestically and worldwide, with incidence rates increasing over the past three decades due to the combination of dietary habits and sedentary lifestyle. Ureteral stents are an important tool to support kidney stone management, but for the past 50 years have not advanced beyond the traditional nondegradable single- or double-curl design requiring a secondary procedure for removal. Pain and discomfort is prevalent, reported for up to 80% of patients, as are other patient inconveniences, such as urinary incontinence. Advances such as lubricious coatings and higher compliance materials have not significantly addressed these concerns and unfortunately, it is established that these traditional stents are a direct cause of pain and discomfort while (1) the stent is in place, and (2) as a result of the secondary stent removal procedure. Due to pain, nearly 4 in 10 patients use opioid medications, a far higher rate than that of non-stented patients. These disadvantages demonstrate a need for new stent concepts. ADVA-Tec, Inc. has developed Uriprene®, a degradable ureteral stent designed to temporarily support drainage from the kidney to the bladder as a part of kidney stone management. Uriprene is a composite tubular structure that provides drainage like other ureteral stents, but softens after implantation and ultimately degrades into compliant pieces that void naturally with urination. An 8-patient pilot clinical study, as well as several pre-clinical evaluations, has confirmed the safety of Uriprene, and preliminary evaluations support the ability of Uriprene to address stent pain and discomfort while in place; Uriprene also eliminates the need for a secondary removal procedure, another significant contributor to pain and discomfort. The objective of this SBIR proposal is to demonstrate the safety, efficacy, incontinence rates, and pain response of Uriprene through a single arm multi-site study. This will be achieved through objective outcome measures such as laboratory and radiographic assessments, including recorded usage of pain medications, as well as through subjective measures such as patient-scored pain through a validated questionnaire. This study will follow 87 patients through the 30-day stent degradation and self-elimination window, and up to 90 days post- surgery as necessary. Stent performance will be statistically evaluated against published historical controls that represent the standard of care. Prior communication with FDA confirms our regulatory path, and successful completion of this study will provide the necessary support to submit the Uriprene degradable stent for regulatory clearance, thereby translating this important device advance to market.