Release Profile of Salofalk 750 mg Tablets

Abstract

This study determined the release profile of Salofalk 750 mg tablets (Axcan Pharma), an enteric-coated 5-aminosalicylic acid (5-ASA) preparation. Twenty-one ileostomates were divided into two groups and studied. Group 1 consisted of 10 subjects (five males, five females, mean age 39 years) who had a mean length of 65 cm of small bowel resected or out of circuit. Group 2 consisted of 11 subjects (eight males, three females, mean age 59 years) whose small bowel was intact. Following an overnight fast and collection of baseline samples, one Salofalk tablet was ingested. Ileostomy effluent and urine were collected for 24 h. Plasma samples were collected hourly for 6 h, then at 8, 12 and 24 h. All subjects ate standardized meals. All samples were stored at --10 degrees C and 5-ASA and N-ac-5-ASA (a metabolite of 5-ASA) were measured by high performance liquid chromatography. The mean intestinal transit time was not statistically different between the groups but the mean ileostomy effluent output was higher in group 1 versus group 2 (10.9 versus 13.1 h, P=0.4; 918 versus 606 mL, P=0.05). The mean peak plasma concentrations of 5-ASA and N-ac-5-ASA were not significantly different (6.12 and 5.42 µ g/ mL, P=0.8, respectively, in group 1 versus 6.75 and 6.66 µ g/mL, P=0.8 in group 2). On average, 33.1% of the ingested dose was recovered in the ileostomy effluent in group 1 versus 21.2% in group 2 (P=0.06) whereas the mean recovery in urine was 40.9% in group 1 but 62.9% in group 2 (P=0.001). These results suggest that 5-ASA is released in the small bowel. There was decreased absorption of 5-ASA and increased recovery of 5-ASA in the ileostomy effluent of subjects who had a small bowel resection.