A prospective, randomized trial of azathioprine monotherapy Versus Azathioprine and olsalazine for the maintenance of remission of sterold-dependent ulcerative colitis

Abstract

BACKGROUND/OBJECTIVES: Since the first use of azathioprine (AZA) in the treatment of chronic ulcerative colitis (UC), there have been several open studies reporting benefit but few controlled trials. The aim of this study was to compare the efficacy of AZA and oral 5-ASA in the treatment of steroid-dependent UC.METHODS:52 patients with steroid-dependent UC (29F, 23M, mean age 42, range 18-72), were admitted to this investigator blind study. Steroiddependence was defined as a requirement of steroid therapy at -> 10 mg/day during the preceding 6 months, with at least 2 attempts to discontinue the medication. The disease had to be clinically and endoscopicelly active at study entry, and all patients were taking systemic prednisolone (40 mg/day). Patients were randomised to receive AZA 2 mg/Kg/day or oral 5ASA 3.2 g/day, for a 6-month follow-up period. Clinical and endoscopic activity was monitored by PowelI-Tuck and Baron indeces, respectively. Physician Global Assessment (PGA)(from 1 = very much improved to 6 = much worse) was evaluated after 6 months. The outcome of the treatment was defined as (1) success = induction of clinical and endoscopic remission and steroid discontinuation, (2) failure = need of at least 1 further cycle of systemic steroids to control symptoms, apart from that initial one or colectomy. RESULTS: 27 patients were treated wit AZA and 25 with 5-ASA.3 patients (1 in AZA and 2 in 5-ASA group) were lost to follow-up. After 6 months, significantly more patients in the AZA than in the 5-ASA group obtained success of therapy.Two patients in the AZA and 2 in the 5-ASA treatment groups had colectomy. PGA was b~er in AZA than in 5-ASA treatment at month 6 (AZA vs 5-ASA = 2.84_+1.75 vs 4.21_+1.80, p<O.01). CONCLUSIONS:AZA therapy is significantly more effective than 5-ASA in inducing clinical and endoscopic remission and avoiding steroid requirement in the treatment of steroid-dependent UC.