An investigation into the efficacy of the pectin based anti-reflux formulation-Aflurax

The properties of the new pectin-based anti-reflux agent Aflurax (Ferrosan) were studied in vitro and in vivo. Aflurax had a significantly higher in v itro raft strength than the placebo which was matched to the active except for the pectin (4.66 +/- 2.10 and 0.22 +/- 0.04 g, respectively). In the mo dified Rossett and Rice test, the pectin raft remained above pH 3 for 130 m in, whereas the pH in the acid phase remained unchanged. A modification to the stirring speed of the Rossett and Rice test was required to obtain a ne utralisation profile for the placebo. The neutralisation profiles for the A flurax and placebo were the same since both contained 5 mEq of base per tab let. In the in vivo study, subjects were randomly assigned to two groups, w hich either received radiolabelled food and unlabelled formulation, or unla belled food and radiolabelled formulations. A pH probe was passed naso-gast rically and placed 5 cm from the cardia, and a small gamma detector was pla ced on the chest wall, coincident with the pH probe. The subjects received the test meal after an overnight fast. The pectin formulation or placebo wa s administered 30 min later. Each part of the study was performed as a sing le-blind two-way cross over with the active versus placebo. The reflux of r adiolabel and acid was monitored for three hours postprandially. Aflurax re duced the H+ concentration (total refluxed hydrogen ion index for Aflurax = 3.5 x 10(3) +/- 2.1 x 10(3), placebo = 29 x 103 +/- 16 x 10(3)) and amount of radiolabelled food reaching the oesophagus (total refluxed count index of food in counts x 1000 min(-1) Aflurax = 19.2 +/- 2.3 placebo = 525 +/- 4 23). The mean time for which the oesophageal pH fell below pH 4 was 2.58 +/ - 1.0 and 0.86 +/- 0.4 minutes for the placebo and Aflurax groups, respecti vely. The total amount of radiolabelled formulation which reached the oesop hagus was 1000 +/- 660 for the placebo and 621 +/- 580 for the Aflurax. (C) 2000 Elsevier Science B.V. All rights reserved.