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

Benign esophageal strictures (BES) cause dysphagia and decrease patients' quality of life. Although mechanical dilation is the standard of care for BES, in some patients, dysphagia is unrelieved despite repeated procedures. The biodegradable stent was developed to resolve refractory BES, with reported favorable outcomes, but it is unapproved in Japan. Thus, we evaluated the safety and efficacy of the biodegradable stent (BDS) for patients with refractory BES for regulatory approval.This was a nonrandomized single-arm prospective trial conducted at eight institutions. We included patients with BES after ≥ 5 times of dilation or ≥ one time of radial incision and cutting whose dysphagia score (DS) was 2 or worse and an endoscope could not admit. The primary endpoint was the proportion of patients whose DS improvement of ≤ 1 was maintained at 3 months.Thirty patients (median age: 69 years, male/female: 27:3) were enrolled and treated; BDS placement failed in 1 patient. Fourteen patients maintained their DS improvement until 3 months after placement (proportion of DS improvement at 3 months 46.7% [95% CI: 28.3-65.7]), and the median dysphagia-free survival was 98 days [95% CI: 68-123]. Most adverse events could be managed conservatively; however, a patient with BES after chemoradiotherapy (CRT) developed an esophago-left atrium fistula and died approximately 4 months after stent placement.The BDS was effective for refractory BES and the safety was acceptable. However, the indication for this procedure in patients RECEIVING CRT for esophageal cancer should be carefully considered.