BACKGROUND: The need is well recognized for additional data on endoluminal therapies for gastroesophageal reflux disease (GERD). This prospective multicenter clinical trial was designed to assess safety and effectiveness of Enteryx, a nonresorbable copolymer implanted into the lower esophagus, in reducing usage of proton pump inhibitors (PPIs) and improving reflux symptoms and quality of life. METHODS: Enteryx implantation was performed under fluoroscopic visualization without general anesthesia in 93 patients with symptomatic GERD responsive to and relapsing upon cessation of PPI therapy. Subjective and objective data were collected up to 12 months postprocedure. The criterion for treatment success was reduction in PPI dosage of > or =50%. RESULTS: At 12 months, treatment success was attained in 86% (confidence interval, 77%-93%) of 74 evaluable patients and elimination of PPI therapy in 65% (confidence interval, 53%-76%). The treatment success rate by intent-to-treat analysis was 69% (confidence interval, 58%-78%). Reflux-related heartburn (P < 0.0001), regurgitation symptoms (P = 0.0005), and physical (P < 0.0001) and mental quality of life (P = 0.0012) scores improved. The most frequent complications were chest pain (77%), dysphagia/odynophagia (27%), and sensation of fever (26%). CONCLUSIONS: Enteryx implantation provides an effective and safe alternative for management of gastroesophageal reflux, reducing medication dependency and symptoms and enhancing quality of life.