Ureteric diseases range from benign to malignant. Targeted drug delivery to the ureter is difficult because of the narrow, tubular nature of the ureter and constant urine flow within.
Current methods comprising endoscopic full-thickness incision of the ureteric wall and placement of an indwelling stent for up to 6 weeks, is not always successful, is associated with recurrent obstruction and hence may require repeated interventions.
The technology is compatible for use with any commercially available ureteral stents. This technology aims to address particularly the problems of benign strictures and malignant disease (carcinoma) of the ureter.
The worldwide market is estimated at 2.8 million stents needed/year; in the US alone, 120,000 stents are implanted per year.
The technology comprises of a layer of anti-proliferative drug incorporated into a polymer, and a second layer of hydrogel which swells as it absorbs urine. The swollen hydrogel directly contacts with the ureteric lining along the length of the stent and enhances the localized delivery of drug into the targeted ureteric tissues.
In vitro drug release studies have demonstrated that the drug, with tunable dosage release rates, can be delivered over a sustained period of 1 month or more (which is the common indwelling stenting duration) and the coated section can swell up to approximately 4.5 – 5 mm in diameter (the common ureteric diameter in adults). The drugs eluted are able to inhibit bladder stroma fibroblasts in vitro.
Currently, in vivo studies with the coated stent are in progress to collect pharmacokinetic, radiological and histological data.
Successful insertion/removal of coated stent in a pig model has been demonstrated.
The team is also working to improve the swelling characteristics of the stent and compare efficacy of different drugs in a uretric injury model.
Current IP Position: Patent Pending (PCT/SG2016/050119 filed on 15 March 2016)
Upon successful in vivo demonstration of drug eluting ureteral stent’s safety and efficacy, the technology is ideally placed to be further developed through first-in-man trials.
Seeking IP licensing to SME/MNC operating in Stents/Stent Coating OR Collaborative technology development with industry partners.
Dr Chong Tsung Wen / SingHealth