Endoscopic Implantation of Enteryx for the Treatment of Gastroesophageal Reflux Disease (GERD): Post Market Study

The Enteryx procedure kit is indicated for endoscopic injection into the region of the lower esophageal sphincter (LES) for the treatment of symptoms due to gastroesophageal reflux disease (GERD) symptoms in patients responding to and requiring daily pharmacological therapy with proton pump inhibitors (PPI's).

The study design consists of two parts, Part A and Part B. Part A will enroll patients who received Enteryx treatments after approval and Part B will enroll patients previously enrolled and treated in the IDE study #G000065. In total there will be at least 300 patients enrolled in Part A and Part B with 36 months of follow-up Part A: Approximately 150 to 200 patients will be enrolled from 22 centers. After patients have determined with their physicians that Enteryx is an appropriate course of therapy for their GERD symptoms, they will be asked to participate in this trial. Patients will be followed for adverse events, medication use, and GERD-HRQL symptoms at baseline, day of treatment, one month, six months, twelve months, twenty-four months, and thirty-six months. The final study visit will be thirty-six months after the last Enteryx injection. In addition, all Part A patients will be contacted by the Site at least quarterly to obtain current adverse event information. This adverse event information will be solicited from the Site by the Sponsor at least quarterly. Part B: All US IDE patients (approximately 150 patients) will be asked to enroll. Patients will be followed for adverse events, medication use, and GERD-HRQL symptoms at two visits beyond the follow-up prescribed in the IDE study, namely 24 and 36 months after the last Enteryx injection received in the IDE study. Parts A and B: There will be a breakdown of adverse events based on retreatment status. Any subsequent procedures or interventions related to GERD or Enteryx, whether surgical (such as fundoplication) or non-surgical (such as an alternative endoscopic treatment for GERD), will be collected and reported.

H0: (Null hypothesis): Proportion of patients exhibiting clinically significant improvement in reduction of PPI therapy ≤ 0.5

Ha: (Alt. hypothesis): Proportion of patients exhibiting clinically significant improvement in reduction of PPI therapy > 0.5

The Sponsor will examine the proportion of patients who have clinically significant reduction in PPI therapy at the 12, 24 and 36 month follow-ups, in an identical manner to that used for the patients in the IDE trial. The "clinically significant reduction" is defined as either elimination of medication use or reduction in dosage of ≥50%. The criterion for success is defined as more than half of patients demonstrating this degree of medication reduction. The hypothesis is tested by p-value and construction of the exact 95% Clopper-Pearson confidence intervals around the observed proportion of patients who meet the criterion for success. The longitudinal post-procedure follow-up data across time (repeated measures) will be analyzed to determine patterns and trends for all primary endpoints. The hypothesis stated above will also be evaluated in the subset of patients that underwent retreatment prior to amendment v.14Oct05.