Indwelling urinary catheters (IUCs) are one of the most commonly used medical devices, with up to a quarter of all hospital patients being catheterized at any given time. In a meta-analysis of 37 studies, 30% of long-term catheterized patients were found to suffer from complications associated with catheterization. Catheter-associated urinary tract infections (CAUTIs) are the most common  of any hospital acquired infection, occurring in over 1 million cases in the United States annually.  In addition, non-infectious complications associated with IUCs are up to 4 times as common as infectious complications.

Latex and silicone-coated latex materials used for conventional IUCs create a perfect nidus for biofilm growth. These rubbers attract organic material to the catheter surface, and initiate biofilm formation within minutes. Biofilm is the primary cause of reoccurring infection and is directly linked to encrustation/calcification/occlusion of catheters. The tacky, rubber catheter surface also causes microtrauma to the urothelial tissue lining the bladder walls and urinary tract, inducing inflammation. As inflammatory factors are secreted in response to catheter placement, pathogenic microbes can use these factors as “scaffolding” to strengthen the biofilm, causing pathogens within biofilms to be approximately 1,000 times more resistant to antibiotics than non-biofilm pathogens.

For the past 20 years, zwitterion chemistry has been identified as one of the most powerful technologies to resist the deposition of organic materials on synthetic surfaces. The technology has been intensively studied during this period, resulting in more than 600 peer-reviewed publications on the properties, clinical benefits and potential applications of zwitterions in the medical field. Emulating the chemistry of the phospholipid bilayer that encompasses every cell in the body, zwitterionic polymers bind to water electrostatically to create an extremely thin hydration layer on the surface of materials. This unique property enables zwitterions to resist biofilm adherence, inflammation/the foreign-body response, and blood coagulation on device surfaces. However, due to the complexity and high cost of the deposition process onto large surfaces, utilization and demonstration of zwitterionic coatings have been previously constrained to academic settings with highly specialized equipment on small samples. Recently, multidisciplinary research among material scientists, chemists, microbiologists, and biomedical engineers at the University of California, Los Angeles has led to the development of a scalable manufacturing process that enables the broad-based use of zwitterionic chemistry on implanted medical devices, such as Foley catheters.

The aim of the studies are to investigate the clinical improvement of zwitterion-treated catheters compared to non-treated, standard of care latex and silver-coated catheters. Two randomized clinical studies are being conducted on long-term catheterized patients that measures biofilm adherence and encrustation on explanted catheters, as well as UTIs, patient quality of life, and complications rates in catheterized patients enrolled in the study.

As of April 3, 2024, there is an observed reduction in biofilm by 60% in the zwitterion-treated catheter group compared with the non-treated and silver-coated catheter groups across 96 patients. In the second, randomized crossover study, there is a 74% and 70% reduction in encrustation and UTIs, respectively, when patients are using the zwitterion-treated catheters versus the standard of care catheter in 50 enrolled patients. Additionally, 13 out of 13 patients who have completed the study have selected the zwitterion-treated catheter as their preferred catheter.

Previous catheter studies have focused single aspects of catheter complications. We believe that the combination of these two real-world studies demonstrate a comprehensive analysis of catheter-related complications, which includes patient input.

Due to the shear volume of catheter-related complications, these early encouraging results demonstrate a large clinical impact that zwitterion technology can have on the chronic-catheter population, a population that have the vast majority of catheter-related complications.