Background: Corticosteroids play a key role in the induction of remission in Crohn's disease. However, corticosteroids can cause significant adverse events. Budesonide is an alternate enteral glucocorticoid with limited systemic bioavailability.
Objectives: The primary objective was to evaluate the efficacy and safety of oral budesonide for the induction of remission in Crohn's disease.
Search strategy: The following electronic databases were searched: MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials, the Cochrane IBD/FBD Group Specialised Trial Register, and ClinicalTrials.gov. Reference lists of articles, as well as conference proceedings were manually searched. Pharmaceutical companies were also contacted.
Selection criteria: Randomized controlled trials comparing budesonide to a control treatment were included. The study population included patients of any age with active Crohn's disease (CDAI > 150). The primary outcome was induction of remission (CDAI < 150) by week 8 to 16 of treatment. Secondary outcomes included: time to remission, mean change in CDAI, clinical, histological or endoscopic improvement, improvement in quality of life, adverse events and early withdrawal.
Data collection and analysis: Two independent investigators reviewed studies for eligibility, extracted the data and assessed study quality. A random effects model was used and studies were weighted using the DerSimonian & Laird method. Meta-analysis was performed using RevMan 4.2.10 software.
Main results: Twelve studies were included: 9 compared budesonide with conventional corticosteroids, 2 were placebo-controlled, and 1 compared budesonide with mesalamine. After 8 weeks of treatment, budesonide was significantly more effective than placebo (RR 1.96, 95% CI 1.19 to 3.23) or mesalamine (RR 1.63; 95% CI 1.23 to 2.16) for induction of remission. Budesonide was significantly less effective than conventional steroids for induction of remission (RR 0.86, 95% CI 0.76 to 0.98), particularly among patients with severe disease (CDAI > 300) (RR 0.52, 95% CI 0.28 to 0.95). Fewer adverse events occurred in those treated with budesonide compared to conventional steroids (RR 0.64, 95% CI 0.54 to 0.76) and budesonide was better able to preserve adrenal function (RR for abnormal ACTH test 0.65, 95% CI 0.55 to 0.78).
Authors' conclusions: Budesonide is more effective than placebo or mesalamine for induction of remission in Crohn's disease. Although short-term efficacy with budesonide is less than with conventional steroids, particularly in those with severe disease or more extensive colonic involvement, the likelihood of adverse events and adrenal suppression is lower.