Objective

Although treatment with corticosteroids induces remission in Crohn's disease, prolonged exposure to corticosteroids is undesirable. This randomised clinical trial evaluated the efficacy of recombinant human granulocyte-macrophage colony-stimulating factor (sargramostim), an activator of innate immunity, in corticosteroid-dependent patients with Crohn's disease.

Design

Patients were randomised in a 2:1 ratio, to sargramostim 6 microg/kg subcutaneously once daily or placebo for up to 22 weeks. The study consisted of (1) an adjunctive phase (weeks 1-4) in which patients received study drug plus corticosteroid therapy; (2) a forced corticosteroid tapering phase (weeks 4-14); and (3) an observation phase (4 weeks) in which patients received study drug plus prednisone < or =7.5 mg. The primary endpoint was corticosteroid-free remission (Crohn's Disease Activity Index (CDAI) < or =150) 4 weeks after corticosteroid elimination. Secondary endpoints were corticosteroid-free response (CDAI decreased by > or =100) and induction of remission in patients who reduced the dose of corticosteroid to 2.5-7.5 mg.

Results

Eighty-seven patients were randomised to sargramostim and 42 to placebo. Significantly more sargramostim-treated patients than placebo patients achieved corticosteroid-free remission (18.6% vs 4.9%; p = 0.03). Similar differences were seen for corticosteroid-free response and in patients who tapered corticosteroids to 2.5-7.5 mg/day. Sargramostim treatment was also associated with significant improvements in health-related quality of life. Patients who received sargramostim were more likely to experience musculoskeletal pain, injection site reactions and dyspnoea.

Conclusions

Sargramostim was more effective than placebo for inducing corticosteroid-free remission in patients with Crohn's disease with corticosteroid dependence. Sargramostim may provide significant benefit in this population if these findings are confirmed.