Pivotal trial of a biodegradable stent for patients with refractory benign esophageal stricture

Comprehensive review of materials, applications, and future innovations in biodegradable esophageal stents

Esophageal stricture (ES) results from benign and malignant conditions, such as uncontrolled gastroesophageal reflux disease (GERD) and esophageal neoplasms. Upper gastrointestinal endoscopy is the preferred diagnostic approach for ES and its underlying causes. Stent insertion using an endoscope is a prevalent method for alleviating or treating ES. Nevertheless, the widely used self-expandable metal stents (SEMS) and self-expandable plastic stents (SEPS) can result in complications such as migration and restenosis. Furthermore, they necessitate secondary extraction in cases of benign esophageal stricture (BES), rendering them unsatisfactory for clinical requirements. Over the past 3 decades, significant attention has been devoted to biodegradable materials, including synthetic polyester polymers and magnesium-based alloys, owing to their exceptional biocompatibility and biodegradability while addressing the challenges associated with recurring procedures after BES resolves. Novel esophageal stents have been developed and are undergoing experimental and clinical trials. Drug-eluting stents (DES) with drug-loading and drug-releasing capabilities are currently a research focal point, offering more efficient and precise ES treatments. Functional innovations have been investigated to optimize stent performance, including unidirectional drug-release and anti-migration features. Emerging manufacturing technologies such as three-dimensional (3D) printing and new biodegradable materials such as hydrogels have also contributed to the innovation of esophageal stents. The ultimate objective of the research and development of these materials is their clinical application in the treatment of ES and other benign conditions and the palliative treatment of malignant esophageal stricture (MES). This review aimed to offer a comprehensive overview of current biodegradable esophageal stent materials and their applications, highlight current research limitations and innovations, and offer insights into future development priorities and directions.

SX-ELLA biodegradable stent for benign oesophageal strictures: a systematic review and proportion meta-analysis

Background

This systematic review aimed to analyse the use of the SX-ELLA biodegradable stent (BDS) for benign oesophageal strictures through the assessment of clinical and technical success, differences in pre- and post-BDS insertion dysphagia scores, rates of stent migration, and safety.

Methods

A systematic review was reported according to PRISMA guidelines, with a prospectively registered protocol. The databases PubMed, Embase, SCOPUS, and ClinicalTrials.gov were searched up to March 2022. Studies assessing the use of the SX-ELLA BDS in adults with benign oesophageal strictures were included. A pooled data analysis was conducted to analyse the clinical and technical success associated with BDS use, rate of stent migration, and safety.

Results

Of the 1509 articles identified, 16 studies treating 246 patients were eligible for inclusion. BDS was clinically successful in 41.9% of cases (95% CI = 35.7 – 48.1%), defined as those who experienced complete symptom resolution following BDS insertion. Technical success was achieved in 97.2% of patients (95% CI = 95.1 – 99.3%). A pooled analysis concluded a decrease in mean dysphagia score of 1.8 points (95% CI = 1.68 – 1.91) following BDS insertion. Re-intervention was required in 89 patients (36.2%, 95% CI = 30.2 – 42.2%), whilst stent migration occurred in 6.5% of patients (95% CI = 3.4 – 9.6%). A total of 37 major clinical complications related to BDS insertion were reported (15.0%, 95% CI = 10.5 – 19.5%).

Conclusion

The pooled data analysis demonstrates the high technical and moderate clinical success of the SX-ELLA biodegradable stent, supporting its use for benign oesophageal strictures in adults. However, greater evidence is required for more robust conclusions to be made in terms of success when compared to alternative methods of intervention, such as endoscopic dilation.