TIF Procedure Clinical Data Overview

The Transoral Incisionless Fundoplication (TIF) procedure is a transoral surgical procedure for the treatment of reflux disease. The TIF procedure is based on the principles of surgical repair of the gastroesophageal junction (GEJ) and is intended to deliver similar benefits as other time-proven fundoplication procedures.

In clinical studies, the TIF procedure has been shown to adequately treat GERD in an appropriately selected patient population. In general, the inclusion criteria were patients >18 years of age with chronic symptomatic GERD > 6 months and demonstrated PPI dependency. The exclusion criteria were patients with severe erosive esophagitis (LA Classification Grade D), BMI > 35, irreducible hiatal hernia > 2 cm, esophageal stricture, presence of Barrett’s epithelial changes in the esophagus, pre-operative dysphagia and esophageal motility disorders.

With these criteria, phase I (n=19) and phase II (n=86) studies were conducted. In addition, a clinical registry (n=38) and a follow-on study looking at the effect that modifications of the original TIF procedure had on the clinical efficacy (n=10) were conducted. The efficacy results are presented in figures 1 and 2 below.

Figure 1. shows the results of the Phase 1 and 2 clinical trials as well as the results from the TIF Registry conducted in Europe. Notably, in the phase 2 trial, patients that had a Hill Grade 1 appearance at 1 year post surgery demonstrated improved clinical outcome in comparison to the study population.

Analysis of the data revealed that there was variability seen in the performance of the wrap and that in particular, those wraps that were less than 200 degrees in circumference had a higher tendency to be loose at 1 year (see Fig 2); hence, underscoring the importance of technique.

Figure 3 shows a comparison of two approaches to performing a TIF procedure.

As demonstrated in Fig 3, the advancing in technique introduced with the TIF2 procedure yielded further improvement in the clinical results. Key differences between the two procedures are the following:

• The TIF1 starts the wrap on the side of the esophagus facing the fundus and works itself back to corners near the less curve vs the TIF2 which starts in the left and right corners on the lesser curve side of the esophagus and then moves to the side facing the fundus
• The TIF1 stresses tensionless repair by not trying to wrap tissue into the corners vs the TIF2 which tucks tissue into the corners accentuating the creation of an omega shaped valve.

Tables 1 and 2 show the safety results for the Phase 1 and 2 studies.

There were 3 serious adverse events in the Phase 2 study: 1) Esophageal perforation during device advancement without adequate visualization with the injury repaired with surgical suture and patient discharge after 6 days, 2) Esophageal perforation upon device insertion into narrow hypopharynx of a patient with Turner syndrome with injury repaired with surgical suture and patient discharge after 21 days and 3) Postoperative intraluminal bleeding at one fastener site that resolved in 5 days without intervention. In all cases, the investigators felt that management by the clinicians themselves was directly a contributing factor to the seriousness of the adverse event.

A complete bibliography of articles written about the TIF procedure in terms of pre-clinical and clinical results can be found in the ARCHIVES section of the website.