Comparison of two different daily dosages (2.4 vs. 1.2 g) of oral mesalazine in maintenance of remission in ulcerative colitis patients: 1-year follow-up study O. A. PAOLUZI, F. IACOPINI, R. PICA, P. CRISPINO, A. MARCHEGGIANO, A. CONSOLAZIO, M. RIVERA & P. PAOLUZI Gastroenterology Unit, Department of Clinical Science, ‘La Sapienza’ University, Rome, Italy Accepted for publication 7 February 2005 SUMMARY Background: Mesalazine as maintenance therapy in ulcerative colitis is used worldwide and has been proven to be effective. However, the optimal dosage remains to be defined. Aim: To establish whether daily treatment with 2.4 g of oral mesalazine is more effective than 1.2 g in prevent- ing disease relapse. Methods: A total of 156 patients with ulcerative colitis in remission were randomly treated for 1 year with 2.4 (n ¼ 80) or 1.2 (n ¼ 76) g/day of mesalazine. Activity of disease was assessed by periodical clinical, endoscopic and histological examinations. Results: After 12 months, 24 of 80 patients (30%) on 2.4 g and 20 of 76 patients (26%) on 1.2 g were still in remission (P ¼ N.S.). Patients in 2.4 g group remained in remission for a longer time than those in 1.2 g group (P < 0.001). Among clinical variables considered in the study, course of disease prior to enrolment ( £ 3/>3 relapses/year) was found to influence response to therapy. Conclusions: A daily dosage of 2.4 g of oral mesalazine seems to better at preventing and delaying relapses of ulcerative colitis than 1.2 g. The course of disease seems to be crucial in choosing the optimal dosage of mesalazine in a maintenance regimen. INTRODUCTION The administration of sulfasalazine (sulphasalazine; SASP) and its derivative 5-aminosalicylic acid (5-ASA) is used throughout the world in the treatment of ulcerative colitis (UC). 1–4 Besides findings in active disease, several studies have demonstrated that 5-ASA is more effective than placebo 5–10 and equally as effective as SASP 11–14 in the maintenance of remission in UC patients. In a recent review by Sutherland et al., 13 results of all double-blind randomized studies published on the efficacy of 5-ASA in the maintenance of remission in UC patients were evaluated and the efficacy of 5-ASA in the prevention of disease relapse was confirmed. Whilst these results deal with the widespread use of 5-ASA, the daily dosage of this drug administered in the different studies, on the other hand, varied considerably, ranging from 0.75 11 to 4.4 g. 14 In a recent report, 15 daily administration of 2 g of 5-ASA has been proposed as the optimal dosage in order to reach a good balance between side-effects and thera- peutic efficacy. As yet, however, the efficacy and tolerability of the different daily dosages of 5-ASA in the prevention of UC relapse have rarely been compared with non-conclusive results as far as concerns the superiority of doubling the dosage of mesalazine. 6, 8, 16 Correspondence to: Prof. P. Paoluzi, Cattedra di Gastroenterologia, Dipartimento di Scienze Cliniche, Viale del Policlinico 157, 00161 Roma, Italy. E-mail: paolo.paoluzi@uniroma1.it Aliment Pharmacol Ther 2005; 21: 1111–1119. doi: 10.1111/j.1365-2036.2005.02458.x Ó 2005 Blackwell Publishing Ltd 1111